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1

Over the last several years the Laser Interferometer Gravitational Wave Observatory (LIGO) has been making steady progress in improving the sensitivities of its three interferometers, two in Hanford, Washington, and one ...

Betzwieser, Joseph (Joseph Charles)

2008-01-01T23:59:59.000Z

2

We calculate and compare the response of light wave interferometers and matter wave interferometers to gravitational waves. We find that metric matter wave interferometers will not challenge kilometric light wave interferometers such as Virgo or LIGO, but could be a good candidate for the detection of very low frequency gravitational waves.

Pacôme Delva; Marie-Christine Angonin; Philippe Tourrenc

2006-09-20T23:59:59.000Z

3

A high-frequency gravitational-wave burst search with LIGO's Hanford site

The Laser Interferometer Gravitational-Wave Observatory (LIGO) is a network of long-arm interferometers designed to directly measure gravitational-wave strain. Direct observation of gravitational waves would provide a test ...

Villadsen, Jacqueline Rose

2009-01-01T23:59:59.000Z

4

A high-frequency gravitational-wave burst search with LIGO's Hanford site .

??The Laser Interferometer Gravitational-Wave Observatory (LIGO) is a network of long-arm interferometers designed to directly measure gravitational-wave strain. Direct observation of gravitational waves would provide… (more)

Villadsen, Jacqueline Rose

2009-01-01T23:59:59.000Z

5

Application of stochastic resonance in gravitational-wave interferometer

We investigate novel approach, which improves the sensitivity of gravitational wave (GW) interferometer due to stochastic resonance (SR) phenomenon, performing in additional nonlinear cavity (NC). The NC is installed in the output of interferometer before photodetector, so that optical signal emerging interferometer incidents on the NC and passes through it. Under appropriate circumstances a specific transformation of noisy signal inside the NC takes place, which results in the increase of output signal-to-noise ratio (SNR). As a result optical noisy signal of interferometer becomes less noisy after passing through the NC. The improvement of SNR is especially effective in bistable NC for wideband (several hundreds Hz) detection, when chirp GW signal is detected. Then SNR gain reaches amount ~ 10. When detection bandwidth is narrowed, the influence of SR mechanism gradually disappears, and SNR gain tends to 1. SNR gain also tends to 1 when the NC is gradually transformed to linear cavity. Proposed enhancement of SNR due to the SR is not dependent of noise type, which is prevalent in interferometer. Particularly proposed approach is capable to increase signal-to-displacement noise ratio.

G. G. Karapetyan

2006-01-30T23:59:59.000Z

6

We present an analysis of high-precision pulsar timing data taken as part of the North American Nanohertz Observatory for Gravitational Waves (NANOGrav) project. We have observed 17 pulsars for a span of roughly five years using the Green Bank and Arecibo radio telescopes. We analyze these data using standard pulsar timing models, with the addition of time-variable dispersion measure and frequency-variable pulse shape terms. Sub-microsecond timing residuals are obtained in nearly all cases, and the best rms timing residuals in this set are {approx}30-50 ns. We present methods for analyzing post-fit timing residuals for the presence of a gravitational wave signal with a specified spectral shape. These optimally take into account the timing fluctuation power removed by the model fit, and can be applied to either data from a single pulsar, or to a set of pulsars to detect a correlated signal. We apply these methods to our data set to set an upper limit on the strength of the nHz-frequency stochastic supermassive black hole gravitational wave background of h{sub c} (1 yr{sup -1}) < 7 Multiplication-Sign 10{sup -15} (95%). This result is dominated by the timing of the two best pulsars in the set, PSRs J1713+0747 and J1909-3744.

Demorest, P. B.; Ransom, S. [National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903 (United States)] [National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903 (United States); Ferdman, R. D.; Kaspi, V. M. [Department of Physics, McGill University, 3600 rue Universite, Montreal, QC H3A 2T8 (Canada)] [Department of Physics, McGill University, 3600 rue Universite, Montreal, QC H3A 2T8 (Canada); Gonzalez, M. E.; Stairs, I. H. [Department of Physics and Astronomy, University of British Columbia, 6224 Agricultural Road, Vancouver, BC V6T 1Z1 (Canada)] [Department of Physics and Astronomy, University of British Columbia, 6224 Agricultural Road, Vancouver, BC V6T 1Z1 (Canada); Nice, D. [Department of Physics, Lafayette College, Easton, PA 18042 (United States)] [Department of Physics, Lafayette College, Easton, PA 18042 (United States); Arzoumanian, Z. [Center for Research and Exploration in Space Science and Technology and X-Ray Astrophysics Laboratory, NASA Goddard Space Flight Center, Code 662, Greenbelt, MD 20771 (United States)] [Center for Research and Exploration in Space Science and Technology and X-Ray Astrophysics Laboratory, NASA Goddard Space Flight Center, Code 662, Greenbelt, MD 20771 (United States); Brazier, A.; Cordes, J. M. [Department of Astronomy, Cornell University, Ithaca, NY 14853 (United States)] [Department of Astronomy, Cornell University, Ithaca, NY 14853 (United States); Burke-Spolaor, S.; Lazio, J. [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91106 (United States)] [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91106 (United States); Chamberlin, S. J.; Ellis, J.; Giampanis, S. [Center for Gravitation, Cosmology and Astrophysics, Department of Physics, University of Wisconsin-Milwaukee, P.O. Box 413, Milwaukee, WI 53201 (United States)] [Center for Gravitation, Cosmology and Astrophysics, Department of Physics, University of Wisconsin-Milwaukee, P.O. Box 413, Milwaukee, WI 53201 (United States); Finn, L. S. [Department of Astronomy and Astrophysics, Pennsylvania State University, University Park, PA 16802 (United States)] [Department of Astronomy and Astrophysics, Pennsylvania State University, University Park, PA 16802 (United States); Freire, P. [Max-Planck-Institut fur Radioastronomie, D-53121 Bonn (Germany)] [Max-Planck-Institut fur Radioastronomie, D-53121 Bonn (Germany); Jenet, F. [Center for Gravitational Wave Astronomy, University of Texas at Brownsville, Brownsville, TX 78520 (United States)] [Center for Gravitational Wave Astronomy, University of Texas at Brownsville, Brownsville, TX 78520 (United States); Lommen, A. N. [Department of Physics and Astronomy, Franklin and Marshall College, P.O. Box 3003, Lancaster, PA 17604 (United States)] [Department of Physics and Astronomy, Franklin and Marshall College, P.O. Box 3003, Lancaster, PA 17604 (United States); McLaughlin, M. [Department of Physics, West Virginia University, P.O. Box 6315, Morgantown, WV 26505 (United States)] [Department of Physics, West Virginia University, P.O. Box 6315, Morgantown, WV 26505 (United States); and others

2013-01-10T23:59:59.000Z

7

We consider a class of proposed gravitational wave detectors based on multiple atomic interferometers separated by large baselines and referenced by common laser systems. We compute the sensitivity limits of these detectors due to intrinsic phase noise of the light sources, non-inertial motion of the light sources, and atomic shot noise and compare them to sensitivity limits for traditional light interferometers. We find that atom interferometers and light interferometers are limited in a nearly identical way by intrinsic phase noise and that both require similar mitigation strategies (e.g. multiple arm instruments) to reach interesting sensitivities. The sensitivity limit from motion of the light sources is slightly different and favors the atom interferometers in the low-frequency limit, although the limit in both cases is severe.

John G. Baker; James Ira Thorpe

2012-01-26T23:59:59.000Z

8

Beyond the Second Generation of Laser-Interferometric Gravitational Wave Observatories

This article gives an overview of potential upgrades of second generation gravitational wave detectors and the required key technologies to improve the limiting noise sources. In addition the baseline design of the Einstein Telescope, a European third generation gravitational wave observatory, is briefly discussed.

Stefan Hild

2011-11-27T23:59:59.000Z

9

Compensation for thermal effects in mirrors of Gravitational Wave Interferometers

In this paper we study several means of compensating for thermal lensing which, otherwise, should be a source of concern for future upgrades of interferometric detectors of gravitational waves. The methods we develop are based on the principle of heating the cold parts of the mirrors. We find that thermal compensation can help a lot but can not do miracles. It seems finally that the best strategy for future upgrades (``advanced configurations'') is maybe to use thermal compensation together with another substrate materials than Silica, for example Sapphire.

P. Hello

2001-04-18T23:59:59.000Z

10

One of the most ambitious goals of gravitational-wave astronomy is to observe the stochastic gravitational-wave background. Correlated noise in two or more detectors can introduce a systematic error, which limits the sensitivity of stochastic searches. We report on measurements of correlated magnetic noise from Schumann resonances at the widely separated LIGO and Virgo detectors. We investigate the effect of this noise on a global network of interferometers and derive a constraint on the allowable coupling of environmental magnetic fields to test mass motion in gravitational-wave detectors. We find that while correlated noise from global electromagnetic fields could be safely ignored for initial LIGO stochastic searches, it could severely impact Advanced LIGO and third-generation detectors.

Eric Thrane; Nelson Christensen; Robert Schofield

2013-03-11T23:59:59.000Z

11

The search for gravitational wave bursts in data from the second LIGO science run

The network of detectors comprising the Laser Interferometer Gravitational-wave Observatory (LIGO) are among a new generation of detectors that seek to make the first direct observation of gravitational waves. While providing ...

Chatterji, Shourov Keith

2005-01-01T23:59:59.000Z

12

Novel approaches to Newtonian noise suppression in interferometric gravitational wave detection

The Laser Interferometer Gravitational-wave Observatory (LIGO) attempts to detect ripples in the curvature of spacetime using two large scale interferometers. These detectors are several kilometer long Michelson interferometers ...

Hunter-Jones, Nicholas R

2011-01-01T23:59:59.000Z

13

We report the results of the first search for gravitational waves from compact binary coalescence using data from the Laser Interferometer Gravitational-Wave Observatory and Virgo detectors. Five months of data were collected ...

Barsotti, Lisa

14

Quantum Noise in Differential-type Gravitational-wave Interferometer and Signal Recycling

There exists the standard quantum limit (SQL), derived from Heisenberg's uncertainty relation, in the sensitivity of laser interferometer gravitational-wave detectors. However, in the context of a full quantum-mechanical approach, SQL can be overcome using the correlation of shot noise and radiation-pressure noise. So far, signal recycling, which is one of the methods to overcome SQL, is considered only in a recombined-type interferometer such as Advanced-LIGO, LCGT, and GEO600. In this paper, we investigated quantum noise and the possibility of signal recycling in a differential-type interferometer. As a result, we found that signal recycling is possible and creates at most three dips in the sensitivity curve of the detector. Then, taking advantage of the third additional dip and comparing the sensitivity of a differential-type interferometer with that of a next-generation Japanese GW interferometer, LCGT, we found that SNR of inspiral binary is improved by a factor of 1.43 for neutron star binary, 2.28 for 50 M_sun black hole binary, and 2.94 for 100 M_sun black hole binary. We also found that power recycling to increase laser power is possible in our signal-recycling configuration of a detector.

Atsushi Nishizawa; Seiji Kawamura; Masa-aki Sakagami

2007-06-03T23:59:59.000Z

15

A stochastic background of gravitational waves is expected to arise from a superposition of many incoherent sources of gravitational waves, of either cosmological or astrophysical origin. This background is a target for the current generation of ground-based detectors. In this article we present the first joint search for a stochastic background using data from the LIGO and Virgo interferometers. In a frequency band of 600-1000 Hz, we obtained a 95% upper limit on the amplitude of $\\Omega_{\\rm GW}(f) = \\Omega_3 (f/900 \\mathrm{Hz})^3$, of $\\Omega_3 < 0.33$, assuming a value of the Hubble parameter of $h_{100}=0.72$. These new limits are a factor of seven better than the previous best in this frequency band.

J. Abadie; B. P. Abbott; R. Abbott; T. D. Abbott; M. Abernathy; T. Accadia; F. Acernese; C. Adams; R. Adhikari; C. Affeldt; M. Agathos; K. Agatsuma; P. Ajith; B. Allen; E. Amador Ceron; D. Amariutei; S. B. Anderson; W. G. Anderson; K. Arai; M. A. Arain; M. C. Araya; S. M. Aston; P. Astone; D. Atkinson; P. Aufmuth; C. Aulbert; B. E. Aylott; S. Babak; P. Baker; G. Ballardin; S. Ballmer; J. C. B. Barayoga; D. Barker; F. Barone; B. Barr; L. Barsotti; M. Barsuglia; M. A. Barton; I. Bartos; R. Bassiri; M. Bastarrika; A. Basti; J. Batch; J. Bauchrowitz; Th. S. Bauer; M. Bebronne; D. Beck; B. Behnke; M. Bejger; M. G. Beker; A. S. Bell; A. Belletoile; I. Belopolski; M. Benacquista; J. M. Berliner; A. Bertolini; J. Betzwieser; N. Beveridge; P. T. Beyersdorf; I. A. Bilenko; G. Billingsley; J. Birch; R. Biswas; M. Bitossi; M. A. Bizouard; E. Black; J. K. Blackburn; L. Blackburn; D. Blair; B. Bland; M. Blom; O. Bock; T. P. Bodiya; C. Bogan; R. Bondarescu; F. Bondu; L. Bonelli; R. Bonnand; R. Bork; M. Born; V. Boschi; S. Bose; L. Bosi; B. Bouhou; S. Braccini; C. Bradaschia; P. R. Brady; V. B. Braginsky; M. Branchesi; J. E. Brau; J. Breyer; T. Briant; D. O. Bridges; A. Brillet; M. Brinkmann; V. Brisson; M. Britzger; A. F. Brooks; D. A. Brown; T. Bulik; H. J. Bulten; A. Buonanno; J. Burguet--Castell; D. Buskulic; C. Buy; R. L. Byer; L. Cadonati; G. Cagnoli; E. Calloni; J. B. Camp; P. Campsie; J. Cannizzo; K. Cannon; B. Canuel; J. Cao; C. D. Capano; F. Carbognani; L. Carbone; S. Caride; S. Caudill; M. Cavagliŕ; F. Cavalier; R. Cavalieri; G. Cella; C. Cepeda; E. Cesarini; O. Chaibi; T. Chalermsongsak; P. Charlton; E. Chassande-Mottin; S. Chelkowski; W. Chen; X. Chen; Y. Chen; A. Chincarini; A. Chiummo; H. Cho; J. Chow; N. Christensen; S. S. Y. Chua; C. T. Y. Chung; S. Chung; G. Ciani; D. E. Clark; J. Clark; J. H. Clayton; F. Cleva; E. Coccia; P. -F. Cohadon; C. N. Colacino; J. Colas; A. Colla; M. Colombini; A. Conte; R. Conte; D. Cook; T. R. Corbitt; M. Cordier; N. Cornish; A. Corsi; C. A. Costa; M. Coughlin; J. -P. Coulon; P. Couvares; D. M. Coward; M. Cowart; D. C. Coyne; J. D. E. Creighton; T. D. Creighton; A. M. Cruise; A. Cumming; L. Cunningham; E. Cuoco; R. M. Cutler; K. Dahl; S. L. Danilishin; R. Dannenberg; S. D'Antonio; K. Danzmann; V. Dattilo; B. Daudert; H. Daveloza; M. Davier; E. J. Daw; R. Day; T. Dayanga; R. De Rosa; D. DeBra; G. Debreczeni; W. Del Pozzo; M. del Prete; T. Dent; V. Dergachev; R. DeRosa; R. DeSalvo; S. Dhurandhar; L. Di Fiore; A. Di Lieto; I. Di Palma; M. Di Paolo Emilio; A. Di Virgilio; M. Díaz; A. Dietz; F. Donovan; K. L. Dooley; M. Drago; R. W. P. Drever; J. C. Driggers; Z. Du; J. -C. Dumas; T. Eberle; M. Edgar; M. Edwards; A. Effler; P. Ehrens; G. Endr\\Hoczi; R. Engel; T. Etzel; K. Evans; M. Evans; T. Evans; M. Factourovich; V. Fafone; S. Fairhurst; Y. Fan; B. F. Farr; D. Fazi; H. Fehrmann; D. Feldbaum; F. Feroz; I. Ferrante; F. Fidecaro; L. S. Finn; I. Fiori; R. P. Fisher; R. Flaminio; M. Flanigan; S. Foley; E. Forsi; L. A. Forte; N. Fotopoulos; J. -D. Fournier; J. Franc; S. Frasca; F. Frasconi; M. Frede; M. Frei; Z. Frei; A. Freise; R. Frey; T. T. Fricke; D. Friedrich; P. Fritschel; V. V. Frolov; M. -K. Fujimoto; P. J. Fulda; M. Fyffe; J. Gair; M. Galimberti; L. Gammaitoni; J. Garcia; F. Garufi; M. E. Gáspár; G. Gemme; R. Geng; E. Genin; A. Gennai; L. Á. Gergely; S. Ghosh; J. A. Giaime; S. Giampanis; K. D. Giardina; A. Giazotto; S. Gil; C. Gill; J. Gleason; E. Goetz; L. M. Goggin; G. González; M. L. Gorodetsky; S. Goßler; R. Gouaty; C. Graef; P. B. Graff; M. Granata; A. Grant; S. Gras; C. Gray; N. Gray; R. J. S. Greenhalgh; A. M. Gretarsson; C. Greverie; R. Grosso; H. Grote; S. Grunewald; G. M. Guidi; R. Gupta; E. K. Gustafson; R. Gustafson; T. Ha; J. M. Hallam; D. Hammer; G. Hammond; J. Hanks; C. Hanna; J. Hanson; J. Harms; G. M. Harry; I. W. Harry; E. D. Harstad; M. T. Hartman; K. Haughian; K. Hayama; J. -F. Hayau; J. Heefner; A. Heidmann; M. C. Heintze; H. Heitmann; P. Hello; M. A. Hendry; I. S. Heng; A. W. Heptonstall; V. Herrera; M. Hewitson; S. Hild; D. Hoak; K. A. Hodge; K. Holt; M. Holtrop; T. Hong; S. Hooper; D. J. Hosken; J. Hough; E. J. Howell; B. Hughey; S. Husa; S. H. Huttner; R. Inta; T. Isogai; A. Ivanov; K. Izumi; M. Jacobson; E. James; Y. J. Jang; P. Jaranowski; E. Jesse; W. W. Johnson; D. I. Jones; G. Jones; R. Jones; L. Ju; P. Kalmus; V. Kalogera; S. Kandhasamy; G. Kang; J. B. Kanner; R. Kasturi; E. Katsavounidis; W. Katzman; H. Kaufer; K. Kawabe; S. Kawamura; F. Kawazoe; D. Kelley; W. Kells; D. G. Keppel; Z. Keresztes; A. Khalaidovski; F. Y. Khalili; E. A. Khazanov; B. Kim; C. Kim; H. Kim; K. Kim; N. Kim; Y. -M. Kim; P. J. King; D. L. Kinzel; J. S. Kissel; S. Klimenko; K. Kokeyama; V. Kondrashov; S. Koranda; W. Z. Korth; I. Kowalska; D. Kozak; O. Kranz; V. Kringel; S. Krishnamurthy; B. Krishnan; A. Królak; G. Kuehn; R. Kumar; P. Kwee; P. K. Lam

2012-02-23T23:59:59.000Z

16

The sensitivity of searches for astrophysical transients in data from the Laser Interferometer Gravitational-wave Observatory (LIGO) is generally limited by the presence of transient, non-Gaussian noise artifacts, which ...

Biswas, Rahul

17

Isolating ground-based interferometric gravitational wave observatories from environmental disturbances is one of the great challenges of the advanced detector era. In order to directly observe gravitational waves, the detector components and test masses must be highly inertially decoupled from the ground motion not only to sense the faint strain of space-time induced by gravitational waves, but also to maintain the resonance of the very sensitive 4 km interferometers. This article presents the seismic isolation instrumentation and strategy developed for Advanced LIGO interferometers. It reviews over a decade of research on active isolation in the context of gravitational wave detection, and presents the performance recently achieved with the Advanced LIGO observatory. Lastly, it discusses prospects for future developments in active seismic isolation and the anticipated benefits to astrophysical gravitational wave searches. Beyond gravitational wave research, the goal of this article is to provide detailed is...

Matichard, F; Mittleman, R; Mason, K; Kissel, J; McIver, J; Abbott, B; Abbott, R; Abbott, S; Allwine, E; Barnum, S; Birch, J; Biscans, S; Celerier, C; Clark, D; Coyne, D; DeBra, D; DeRosa, R; Evans, M; Foley, S; Fritschel, P; Giaime, J A; Gray, C; Grabeel, G; Hanson, J; Hardham, C; Hillard, M; Hua, W; Kucharczyk, C; Landry, M; Roux, A Le; Lhuillier, V; Macleod, D; Macinnis, M; Mitchell, R; Reilly, B O; Ottaway, D; Paris, H; Pele, A; Puma, M; Radkins, H; Ramet, C; Robinson, M; Ruet, L; Sarin, P; Shoemaker, D; Stein, A; Thomas, J; Vargas, M; Venkateswara, K; Warner, J; Wen, S

2015-01-01T23:59:59.000Z

18

Sensing and control in dual-recycling laser interferometer gravitational-wave detectors

gravitational waves are generated when objects with masses of the order of 1 solar mass un- dergo extreme, the light beams make multiple traversals of the varying opti- cal path in the original Michelson-23, 3251 Hanover Street, Palo Alto, California 94304. D. A. Shaddock, M. B. Gray, C. Mow-Lowry, and D. E. M

Tanner, David B.

19

A stochastic background of gravitational waves is expected to arise from a superposition of many incoherent sources of gravitational waves, of either cosmological or astrophysical origin. This background is a target for ...

Barsotti, Lisa

20

We present a possible observing scenario for the Advanced LIGO and Advanced Virgo gravitational wave detectors over the next decade, with the intention of providing information to the astronomy community to facilitate planning for multi-messenger astronomy with gravitational waves. We determine the expected sensitivity of the network to transient gravitational-wave signals, and study the capability of the network to determine the sky location of the source. For concreteness, we focus primarily on gravitational-wave signals from the inspiral of binary neutron star (BNS) systems, as the source considered likely to be the most common for detection and also promising for multimessenger astronomy. We find that confident detections will likely require at least 2 detectors operating with BNS sensitive ranges of at least 100 Mpc, while ranges approaching 200 Mpc should give at least ~1 BNS detection per year even under pessimistic predictions of signal rates. The ability to localize the source of the detected signals depends on the geographical distribution of the detectors and their relative sensitivity, and can be as large as thousands of square degrees with only 2 sensitive detectors operating. Determining the sky position of a significant fraction of detected signals to areas of 5 sq deg to 20 sq deg will require at least 3 detectors of sensitivity within a factor of ~2 of each other and with a broad frequency bandwidth. Should one of the LIGO detectors be relocated in India as expected, many gravitational-wave signals will be localized to a few square degrees by gravitational-wave observations alone.

LIGO Scientific Collaboration; Virgo Collaboration; J. Aasi; J. Abadie; B. P. Abbott; R. Abbott; T. D. Abbott; M. Abernathy; T. Accadia; F. Acernese; C. Adams; T. Adams; P. Addesso; R. X. Adhikari; C. Affeldt; M. Agathos; O. D. Aguiar; P. Ajith; B. Allen; A. Allocca; E. Amador Ceron; D. Amariutei; S. B. Anderson; W. G. Anderson; K. Arai; M. C. Araya; C. Arceneaux; S. Ast; S. M. Aston; P. Astone; D. Atkinson; P. Aufmuth; C. Aulbert; L. Austin; B. E. Aylott; S. Babak; P. Baker; G. Ballardin; S. Ballmer; Y. Bao; J. C. Barayoga; D. Barker; F. Barone; B. Barr; L. Barsotti; M. Barsuglia; M. A. Barton; I. Bartos; R. Bassiri; M. Bastarrika; A. Basti; J. Batch; J. Bauchrowitz; Th. S. Bauer; M. Bebronne; B. Behnke; M. Bejger; M. G. Beker; A. S. Bell; C. Bell; G. Bergmann; J. M. Berliner; A. Bertolini; J. Betzwieser; N. Beveridge; P. T. Beyersdorf; T. Bhadbade; I. A. Bilenko; G. Billingsley; J. Birch; S. Biscans; M. Bitossi; M. A. Bizouard; E. Black; J. K. Blackburn; L. Blackburn; D. Blair; B. Bland; M. Blom; O. Bock; T. P. Bodiya; C. Bogan; C. Bond; F. Bondu; L. Bonelli; R. Bonnand; R. Bork; M. Born; V. Boschi; S. Bose; L. Bosi; B. Bouhou; J. Bowers; C. Bradaschia; P. R. Brady; V. B. Braginsky; M. Branchesi; J. E. Brau; J. Breyer; T. Briant; D. O. Bridges; A. Brillet; M. Brinkmann; V. Brisson; M. Britzger; A. F. Brooks; D. A. Brown; D. D. Brown; F. Brueckner; K. Buckland; T. Bulik; H. J. Bulten; A. Buonanno; J. Burguet-Castell; D. Buskulic; C. Buy; R. L. Byer; L. Cadonati; G. Cagnoli; E. Calloni; J. B. Camp; P. Campsie; K. Cannon; B. Canuel; J. Cao; C. D. Capano; F. Carbognani; L. Carbone; S. Caride; A. D. Castiglia; S. Caudill; M. Cavagliŕ; F. Cavalier; R. Cavalieri; G. Cella; C. Cepeda; E. Cesarini; T. Chalermsongsak; S. Chao; P. Charlton; E. Chassande-Mottin; X. Chen; Y. Chen; A. Chincarini; A. Chiummo; H. S. Cho; J. Chow; N. Christensen; Q. Chu; S. S. Y. Chua; C. T. Y. Chung; G. Ciani; F. Clara; D. E. Clark; J. A. Clark; F. Cleva; E. Coccia; P. -F. Cohadon; C. N. Colacino; A. Colla; M. Colombini; M. Constancio Jr; A. Conte; D. Cook; T. R. Corbitt; M. Cordier; N. Cornish; A. Corsi; C. A. Costa; M. Coughlin; J. -P. Coulon; S. Countryman; P. Couvares; D. M. Coward; M. Cowart; D. C. Coyne; K. Craig; J. D. E. Creighton; T. D. Creighton; A. Cumming; L. Cunningham; E. Cuoco; K. Dahl; M. Damjanic; S. L. Danilishin; S. D'Antonio; K. Danzmann; V. Dattilo; B. Daudert; H. Daveloza; M. Davier; G. S. Davies; E. J. Daw; T. Dayanga; R. De Rosa; G. Debreczeni; J. Degallaix; W. Del Pozzo; E. Deleeuw; T. Denker; T. Dent; V. Dergachev; R. DeRosa; R. DeSalvo; S. Dhurandhar; L. Di Fiore; A. Di Lieto; I. Di Palma; A. Di Virgilio; M. Díaz; A. Dietz; F. Donovan; K. L. Dooley; S. Doravari; M. Drago; S. Drasco; R. W. P. Drever; J. C. Driggers; Z. Du; J. -C. Dumas; S. Dwyer; T. Eberle; M. Edwards; A. Effler; P. Ehrens; S. S. Eikenberry; G. Endröczi; R. Engel; R. Essick; T. Etzel; K. Evans; M. Evans; T. Evans; M. Factourovich; V. Fafone; S. Fairhurst; Q. Fang; B. F. Farr; W. Farr; M. Favata; D. Fazi; H. Fehrmann; D. Feldbaum; I. Ferrante; F. Ferrini; F. Fidecaro; L. S. Finn; I. Fiori; R. P. Fisher; R. Flaminio; S. Foley; E. Forsi; L. A. Forte; N. Fotopoulos; J. -D. Fournier; J. Franc; S. Franco; S. Frasca; F. Frasconi; M. Frede; M. A. Frei; Z. Frei; A. Freise; R. Frey; T. T. Fricke; D. Friedrich; P. Fritschel; V. V. Frolov; M. -K. Fujimoto; P. J. Fulda; M. Fyffe; J. Gair; M. Galimberti; L. Gammaitoni; J. Garcia; F. Garufi; M. E. Gáspár; N. Gehrels; G. Gelencser; G. Gemme; E. Genin; A. Gennai; L. Á. Gergely; S. Ghosh; J. A. Giaime; S. Giampanis; K. D. Giardina; A. Giazotto; S. Gil-Casanova; C. Gill; J. Gleason; E. Goetz; G. González; N. Gordon; M. L. Gorodetsky; S. Gossan; S. Goßler; R. Gouaty; C. Graef; P. B. Graff; M. Granata; A. Grant; S. Gras; C. Gray; R. J. S. Greenhalgh; A. M. Gretarsson; C. Griffo; H. Grote; K. Grover; S. Grunewald; G. M. Guidi; C. Guido; E. K. Gustafson; R. Gustafson; D. Hammer; G. Hammond; J. Hanks; C. Hanna; J. Hanson; K. Haris; J. Harms; G. M. Harry; I. W. Harry; E. D. Harstad; M. T. Hartman; K. Haughian; K. Hayama; J. Heefner; A. Heidmann; M. C. Heintze; H. Heitmann; P. Hello; G. Hemming; M. A. Hendry; I. S. Heng; A. W. Heptonstall; M. Heurs; M. Hewitson; S. Hild; D. Hoak; K. A. Hodge; K. Holt; M. Holtrop; T. Hong; S. Hooper; J. Hough; E. J. Howell; V. Huang; E. A. Huerta; B. Hughey; S. H. Huttner; M. Huynh; T. Huynh-Dinh; D. R. Ingram; R. Inta; T. Isogai; A. Ivanov; B. R. Iyer; K. Izumi; M. Jacobson; E. James; H. Jang; Y. J. Jang; P. Jaranowski; E. Jesse; W. W. Johnson; D. Jones; D. I. Jones; R. Jones; R. J. G. Jonker; L. Ju; P. Kalmus; V. Kalogera; S. Kandhasamy; G. Kang; J. B. Kanner; M. Kasprzack; R. Kasturi; E. Katsavounidis; W. Katzman; H. Kaufer; K. Kawabe; S. Kawamura; F. Kawazoe; D. Keitel; D. Kelley; W. Kells; D. G. Keppel; A. Khalaidovski; F. Y. Khalili; E. A. Khazanov

2013-04-02T23:59:59.000Z

While these samples are representative of the content of NLE

they are not comprehensive nor are they the most current set.

We encourage you to perform a real-time search of NLE

to obtain the most current and comprehensive results.

21

Gravitational wave astronomy and cosmology

The first direct observation of gravitational waves' action upon matter has recently been reported by the BICEP2 experiment. Advanced ground-based gravitational-wave detectors are being installed. They will soon be commissioned, and then begin searches for high-frequency gravitational waves at a sensitivity level that is widely expected to reach events involving compact objects like stellar mass black holes and neutron stars. Pulsar timing arrays continue to improve the bounds on gravitational waves at nanohertz frequencies, and may detect a signal on roughly the same timescale as ground-based detectors. The science case for space-based interferometers targeting millihertz sources is very strong. The decade of gravitational-wave discovery is poised to begin. In this writeup of a talk given at the 2013 TAUP conference, we will briefly review the physics of gravitational waves and gravitational-wave detectors, and then discuss the promise of these measurements for making cosmological measurements in the near future.

Scott A. Hughes

2014-05-02T23:59:59.000Z

22

LIGO interferometer operating at design sensitivity with application to gravitational radiometry

During the last decade the three interferometers of the Laser Interferometer Gravitational Wave Observatory (LIGO) were built and commissioned. In fall 2005 design sensitivity was achieved, corresponding to a strain ...

Ballmer, Stefan W. (Stefan Werner)

2006-01-01T23:59:59.000Z

23

Beating the spin-down limit on gravitational wave emission from the Crab pulsar

We present direct upper limits on gravitational wave emission from the Crab pulsar using data from the first nine months of the fifth science run of the Laser Interferometer Gravitational-wave Observatory (LIGO). These limits are based on two searches. In the first we assume that the gravitational wave emission follows the observed radio timing, giving an upper limit on gravitational wave emission that beats indirect limits inferred from the spin-down and braking index of the pulsar and the energetics of the nebula. In the second we allow for a small mismatch between the gravitational and radio signal frequencies and interpret our results in the context of two possible gravitational wave emission mechanisms.

The LIGO Scientific Collaboration; B. Abbott; R. Abbott; R. Adhikari; P. Ajith; B. Allen; G. Allen; R. Amin; S. B. Anderson; W. G. Anderson; M. A. Arain; M. Araya; H. Armandula; P. Armor; Y. Aso; S. Aston; P. Aufmuth; C. Aulbert; S. Babak; S. Ballmer; H. Bantilan; B. C. Barish; C. Barker; D. Barker; B. Barr; P. Barriga; M. A. Barton; M. Bastarrika; K. Bayer; J. Betzwieser; P. T. Beyersdorf; I. A. Bilenko; G. Billingsley; R. Biswas; E. Black; K. Blackburn; L. Blackburn; D. Blair; B. Bland; T. P. Bodiya; L. Bogue; R. Bork; V. Boschi; S. Bose; P. R. Brady; V. B. Braginsky; J. E. Brau; M. Brinkmann; A. Brooks; D. A. Brown; G. Brunet; A. Bullington; A. Buonanno; O. Burmeister; R. L. Byer; L. Cadonati; G. Cagnoli; J. B. Camp; J. Cannizzo; K. Cannon; J. Cao; L. Cardenas; T. Casebolt; G. Castaldi; C. Cepeda; E. Chalkley; P. Charlton; S. Chatterji; S. Chelkowski; Y. Chen; N. Christensen; D. Clark; J. Clark; T. Cokelaer; R. Conte; D. Cook; T. Corbitt; D. Coyne; J. D. E. Creighton; A. Cumming; L. Cunningham; R. M. Cutler; J. Dalrymple; K. Danzmann; G. Davies; D. DeBra; J. Degallaix; M. Degree; V. Dergachev; S. Desai; R. DeSalvo; S. Dhurandhar; M. Díaz; J. Dickson; A. Dietz; F. Donovan; K. L. Dooley; E. E. Doomes; R. W. P. Drever; I. Duke; J. -C. Dumas; R. J. Dupuis; J. G. Dwyer; C. Echols; A. Effler; P. Ehrens; E. Espinoza; T. Etzel; T. Evans; S. Fairhurst; Y. Fan; D. Fazi; H. Fehrmann; M. M. Fejer; L. S. Finn; K. Flasch; N. Fotopoulos; A. Freise; R. Frey; T. Fricke; P. Fritschel; V. V. Frolov; M. Fyffe; J. Garofoli; I. Gholami; J. A. Giaime; S. Giampanis; K. D. Giardina; K. Goda; E. Goetz; L. Goggin; G. González; S. Gossler; R. Gouaty; A. Grant; S. Gras; C. Gray; M. Gray; R. J. S. Greenhalgh; A. M. Gretarsson; F. Grimaldi; R. Grosso; H. Grote; S. Grunewald; M. Guenther; E. K. Gustafson; R. Gustafson; B. Hage; J. M. Hallam; D. Hammer; C. Hanna; J. Hanson; J. Harms; G. Harry; E. Harstad; K. Hayama; T. Hayler; J. Heefner; I. S. Heng; M. Hennessy; A. Heptonstall; M. Hewitson; S. Hild; E. Hirose; D. Hoak; D. Hosken; J. Hough; S. H. Huttner; D. Ingram; M. Ito; A. Ivanov; B. Johnson; W. W. Johnson; D. I. Jones; G. Jones; R. Jones; L. Ju; P. Kalmus; V. Kalogera; S. Kamat; J. Kanner; D. Kasprzyk; E. Katsavounidis; K. Kawabe; S. Kawamura; F. Kawazoe; W. Kells; D. G. Keppel; F. Ya. Khalili; R. Khan; E. Khazanov; C. Kim; P. King; J. S. Kissel; S. Klimenko; K. Kokeyama; V. Kondrashov; R. K. Kopparapu; D. Kozak; I. Kozhevatov; B. Krishnan; P. Kwee; P. K. Lam; M. Landry; M. M. Lang; B. Lantz; A. Lazzarini; M. Lei; N. Leindecker; V. Leonhardt; I. Leonor; K. Libbrecht; H. Lin; P. Lindquist; N. A. Lockerbie; D. Lodhia; M. Lormand; P. Lu; M. Lubinski; A. Lucianetti; H. Lück; B. Machenschalk; M. MacInnis; M. Mageswaran; K. Mailand; V. Mandic; S. Márka; Z. Márka; A. Markosyan; J. Markowitz; E. Maros; I. Martin; R. M. Martin; J. N. Marx; K. Mason; F. Matichard; L. Matone; R. Matzner; N. Mavalvala; R. McCarthy; D. E. McClelland; S. C. McGuire; M. McHugh; G. McIntyre; G. McIvor; D. McKechan; K. McKenzie; T. Meier; A. Melissinos; G. Mendell; R. A. Mercer; S. Meshkov; C. J. Messenger; D. Meyers; J. Miller; J. Minelli; S. Mitra; V. P. Mitrofanov; G. Mitselmakher; R. Mittleman; O. Miyakawa; B. Moe; S. Mohanty; G. Moreno; K. Mossavi; C. MowLowry; G. Mueller; S. Mukherjee; H. Mukhopadhyay; H. Müller-Ebhardt; J. Munch; P. Murray; E. Myers; J. Myers; T. Nash; J. Nelson; G. Newton; A. Nishizawa; K. Numata; J. O'Dell; G. Ogin; B. O'Reilly; R. O'Shaughnessy; D. J. Ottaway; R. S. Ottens; H. Overmier; B. J. Owen; Y. Pan; C. Pankow; M. A. Papa; V. Parameshwaraiah; P. Patel; M. Pedraza; S. Penn; A. Perreca; T. Petrie; I. M. Pinto; M. Pitkin; H. J. Pletsch; M. V. Plissi; F. Postiglione; M. Principe; R. Prix; V. Quetschke; F. Raab; D. S. Rabeling; H. Radkins; N. Rainer; M. Rakhmanov; M. Ramsunder; H. Rehbein; S. Reid; D. H. Reitze; R. Riesen; K. Riles; B. Rivera; N. A. Robertson; C. Robinson; E. L. Robinson; S. Roddy; A. Rodriguez; A. M. Rogan; J. Rollins; J. D. Romano; J. Romie; R. Route; S. Rowan; A. Rüdiger; L. Ruet; P. Russell; K. Ryan; S. Sakata; M. Samidi; L. Sancho de la Jordana; V. Sandberg; V. Sannibale; S. Saraf; P. Sarin; B. S. Sathyaprakash; S. Sato; P. R. Saulson; R. Savage; P. Savov; S. W. Schediwy; R. Schilling; R. Schnabel; R. Schofield; B. F. Schutz; P. Schwinberg; S. M. Scott; A. C. Searle; B. Sears; F. Seifert; D. Sellers; A. S. Sengupta; P. Shawhan; D. H. Shoemaker; A. Sibley; X. Siemens; D. Sigg; S. Sinha; A. M. Sintes; B. J. J. Slagmolen; J. Slutsky; J. R. Smith; M. R. Smith; N. D. Smith; K. Somiya; B. Sorazu; L. C. Stein; A. Stochino; R. Stone; K. A. Strain; D. M. Strom; A. Stuver; T. Z. Summerscales; K. -X. Sun; M. Sung; P. J. Sutton; H. Takahashi; D. B. Tanner; R. Taylor; R. Taylor; J. Thacker; K. A. Thorne; K. S. Thorne; A. Thüring; K. V. Tokmakov; C. Torres; C. Torrie; G. Traylor; M. Trias; W. Tyler

2008-07-22T23:59:59.000Z

24

We have performed a search for bursts of gravitational waves associated with the very bright Gamma Ray Burst GRB030329, using the two detectors at the LIGO Hanford Observatory. Our search covered the most sensitive frequency range of the LIGO detectors (approximately 80-2048 Hz), and we specifically targeted signals shorter than 150 ms. Our search algorithm looks for excess correlated power between the two interferometers and thus makes minimal assumptions about the gravitational waveform. We observed no candidates with gravitational wave signal strength larger than a pre-determined threshold. We report frequency dependent upper limits on the strength of the gravitational waves associated with GRB030329. Near the most sensitive frequency region, around 250 Hz, our root-sum-square (RSS) gravitational wave strain sensitivity for optimally polarized bursts was better than h_RSS = 6E-21 Hz^{-1/2}. Our result is comparable to the best published results searching for association between gravitational waves and GRBs.

The LIGO Scientific Collaboration

2005-06-24T23:59:59.000Z

25

We have performed a search for bursts of gravitational waves associated with the very bright Gamma Ray Burst GRB030329, using the two detectors at the LIGO Hanford Observatory. Our search covered the most sensitive frequency range of the LIGO detectors (approximately 80-2048 Hz), and we specifically targeted signals shorter than 150 ms. Our search algorithm looks for excess correlated power between the two interferometers and thus makes minimal assumptions about the gravitational waveform. We observed no candidates with gravitational wave signal strength larger than a pre-determined threshold. We report frequency dependent upper limits on the strength of the gravitational waves associated with GRB030329. Near the most sensitive frequency region, around 250 Hz, our root-sum-square (RSS) gravitational wave strain sensitivity for optimally polarized bursts was better than h_RSS = 6E-21 Hz^{-1/2}. Our result is comparable to the best published results searching for association between gravitational waves and GRBs...

Abbott, R; Ageev, A; Allen, B; Amin, R; Anderson, S B; Anderson, W G; Araya, M; Armandula, H; Ashley, M; Asiri, F; Aufmuth, P; Aulbert, C; Babak, S; Balasubramanian, R; Ballmer, S; Barish, B C; Barker, C; Barker, D; Barnes, M; Barr, B; Barton, M A; Bayer, K; Beausoleil, R; Belczynski, K; Bennett, R; Berukoff, S J; Betzwieser, J; Bhawal, B; Bilenko, I A; Billingsley, G; Black, E; Blackburn, K; Blackburn, L; Bland, B; Bochner, B; Bogue, L; Bork, R; Bose, S; Brady, P R; Braginsky, V B; Brau, J E; Brown, D A; Bullington, A; Bunkowski, A; Buonanno, A; Burgess, R; Busby, D; Butler, W E; Byer, R L; Cadonati, L; Cagnoli, G; Camp, J B; Cantley, C A; Cardenas, L; Carter, K; Casey, M M; Castiglione, J; Chandler, A; Chapsky, J; Charlton, P; Chatterji, S; Chelkowski, S; Chen, Y; Chickarmane, V; Chin, D; Christensen, N; Churches, D; Cokelaer, T; Colacino, C; Coldwell, R; Coles, M; Cook, D; Corbitt, T; Coyne, D; Creighton, J D E; Creighton, T D; Crooks, D R M; Csatorday, P; Cusack, B J; Cutler, C; D'Ambrosio, E; Danzmann, K; Daw, E; De Bra, D; Delker, T; Dergachev, V; DeSalvo, R; Dhurandhar, S V; Di Credico, A; Díaz, M; Ding, H; Drever, R W P; Dupuis, R J; Edlund, J A; Ehrens, P; Elliffe, E J; Etzel, T; Evans, M; Evans, T; Fairhurst, S; Fallnich, C; Farnham, D; Fejer, M M; Findley, T; Fine, M; Finn, L S; Franzen, K Y; Freise, A; Frey, R; Fritschel, P; Frolov, V V; Fyffe, M; Ganezer, K S; Garofoli, J; Giaime, J A; Gillespie, A; Goda, K; González, G; Goler, S; Grandclément, P; Grant, A; Gray, C; Gretarsson, A M; Grimmett, D; Grote, H; Grünewald, S; Günther, M; Gustafson, E; Gustafson, R; Hamilton, W O; Hammond, M; Hanson, J; Hardham, C; Harms, J; Harry, G; Hartunian, A; Heefner, J; Hefetz, Y; Heinzel, G; Heng, I S; Hennessy, M; Hepler, N; Heptonstall, A; Heurs, M; Hewitson, M; Hild, S; Hindman, N; Hoang, P; Hough, J; Hrynevych, M; Hua, W; Ito, M; Itoh, Y; Ivanov, A; Jennrich, O; Johnson, B; Johnson, W W; Johnston, W R; Jones, D I; Jones, L; Jungwirth, D; Kalogera, V; Katsavounidis, E; Kawabe, K; Kawamura, S; Kells, W; Kern, J; Khan, A; Killbourn, S; Killow, C J; Kim, C; King, C; King, P; Klimenko, S; Koranda, S; Kotter, K; Kovalik, Yu; Kozak, D; Krishnan, B; Landry, M; Langdale, J; Lantz, B; Lawrence, R; Lazzarini, A; Lei, M; Leonor, I; Libbrecht, K; Libson, A; Lindquist, P; Liu, S; Logan, J; Lormand, M; Lubinski, M; Luck, H; Lyons, T T; Machenschalk, B; MacInnis, M; Mageswaran, M; Mailand, K; Majid, W; Malec, M; Mann, F; Marin, A; Marka, S; Maros, E; Mason, J; Mason, K; Matherny, O; Matone, L; Mavalvala, N; McCarthy, R; McClelland, D E; McHugh, M; McNabb, J W C; Mendell, G; Mercer, R A; Meshkov, S; Messaritaki, E; Messenger, C; Mitrofanov, V P; Mitselmakher, G; Mittleman, R; Miyakawa, O; Miyoki, S; Mohanty, S; Moreno, G; Mossavi, K; Müller, G; Mukherjee, S; Murray, P; Myers, J; Nagano, S; Nash, T; Nayak, R; Newton, G; Nocera, F; Noel, J S; Nutzman, P; Olson, T; O'Reilly, B; Ottaway, D J; Ottewill, A; Ouimette, D A; Overmier, H; Owen, B J; Pan, Y; Papa, M A; Parameshwaraiah, V; Parameswariah, C; Pedraza, M; Penn, S; Pitkin, M; Plissi, M; Prix, R; Quetschke, V; Raab, F; Radkins, H; Rahkola, R; Rakhmanov, M; Rao, S R; Rawlins, K; Ray-Majumder, S; Re, V; Redding, D; Regehr, M W; Regimbau, T; Reid, S; Reilly, K T; Reithmaier, K; Reitze, D H; Richman, S; Riesen, R; Riles, K; Rivera, B; Rizzi, A; Robertson, D I; Robertson, N A; Robison, L; Roddy, S; Rollins, J; Romano, J D; Romie, J; Rong, H; Rose, D; Rotthoff, E; Rowan, S; Rüdiger, A; Russell, P; Ryan, K; Salzman, I; Sandberg, V; Sanders, G H; Sannibale, V; Sathyaprakash, B; Saulson, P R; Savage, R; Sazonov, A; Schilling, R; Schlaufman, K; Schmidt, V; Schnabel, R; Schofield, R; Schutz, B F; Schwinberg, P; Scott, S M; Seader, S E; Searle, A C; Sears, B; Seel, S; Seifert, F; Sengupta, A S; Shapiro, C A; Shawhan, P; Shoemaker, D H; Shu, Q Z; Sibley, A; Siemens, X; Sievers, L; Sigg, D; Sintes, A M; Smith, J R; Smith, M; Smith, M R; Sneddon, P H; Spero, R; Stapfer, G; Steussy, D; Strain, K A; Strom, D; Stuver, A; Summerscales, T; Sumner, M C; Sutton, P J; Sylvestre, J; Takamori, A; Tanner, D B; Tariq, H; Taylor, I; Taylor, R; Taylor, R; Thorne, K A; Thorne, K S; Tibbits, M; Tilav, S; Tinto, M; Tokmakov, K V; Torres, C; Torrie, C; Traylor, G; Tyler, W; Ugolini, D W; Ungarelli, C; Vallisneri, M; Van Putten, M H P M; Vass, S; Vecchio, A; Veitch, J; Vorvick, C; Vyachanin, S P; Wallace, L; Walther, H; Ward, H; Ware, B; Watts, K; Webber, D; Weidner, A; Weiland, U; Weinstein, A; Weiss, R; Welling, H; Wen, L; Wen, S; Whelan, J T; Whitcomb, S E; Whiting, B F; Wiley, S; Wilkinson, C; Willems, P A; Williams, P R; Williams, R; Willke, B; Wilson, A; Winjum, B J; Winkler, W; Wise, S; Wiseman, A G; Woan, G; Wooley, R; Worden, J; Wu, W; Yakushin, I; Yamamoto, H; Yoshida, S; Zaleski, K D; Zanolin, M; Zawischa, I; Zhang, L; Zhu, R; Zotov, N P; Zucker, M; Zweizig, J

2005-01-01T23:59:59.000Z

26

LIGO and the Search for Gravitational Waves

Gravitational waves, predicted to exist by Einstein's General Theory of Relativity but as yet undetected, are expected to be emitted during violent astrophysical events such as supernovae, black hole interactions and the coalescence of compact binary systems. Their detection and study should lead to a new branch of astronomy. However the experimental challenge is formidable: ground-based detection relies on sensing displacements of order 10{sup -18} m over a frequency range of tens of hertz to a few kHz. There is currently a large international effort to commission and operate long baseline interferometric detectors including those that comprise LIGO - the Laser Interferometer Gravitational-Wave Observatory - in the USA. In this talk I will give an introduction to the topic of gravitational wave detection and in particular review the status of the LIGO project which is currently taking data at its design sensitivity. I will also look to the future to consider planned improvements in sensitivity for such detectors, focusing on Advanced LIGO, the proposed upgrade to the LIGO project.

Robertson, Norna A.

2006-10-16T23:59:59.000Z

27

No evidence for the blue-tilted power spectrum of relic gravitational waves

In this paper, we constrain the tilt of the power spectrum of relic gravitational waves by combining the data from BICEP2/Keck array and Planck (BKP) and the Laser Interferometer Gravitational-Waves Observatory (LIGO). From the data of BKP B-modes, the constraint on the tensor tilt is $n_t=0.66^{+1.83}_{-1.44}$ at the $68%$ confidence level. By further adding the LIGO upper limit on the energy density of gravitational waves, the constraint becomes $n_t=-0.76^{+1.37}_{-0.52}$ at the $68%$ confidence level. We conclude that there is no evidence for a blue-tilted power spectrum of relic gravitational waves and either sign of the index of tensor power spectrum is compatible with the data.

Huang, Qing-Guo

2015-01-01T23:59:59.000Z

28

No evidence for the blue-tilted power spectrum of relic gravitational waves

In this paper, we constrain the tilt of the power spectrum of relic gravitational waves by combining the data from BICEP2/Keck array and Planck (BKP) and the Laser Interferometer Gravitational-Waves Observatory (LIGO). From the data of BKP B-modes, the constraint on the tensor tilt is $n_t=0.66^{+1.83}_{-1.44}$ at the $68%$ confidence level. By further adding the LIGO upper limit on the energy density of gravitational waves, the constraint becomes $n_t=-0.76^{+1.37}_{-0.52}$ at the $68%$ confidence level. We conclude that there is no evidence for a blue-tilted power spectrum of relic gravitational waves and either sign of the index of tensor power spectrum is compatible with the data.

Qing-Guo Huang; Sai Wang

2015-02-09T23:59:59.000Z

29

Resonant speed meter for gravitational wave detection

Gravitational-wave detectors have been well developed and operated with high sensitivity. However, they still suffer from mirror displacement noise. In this paper, we propose a resonant speed meter, as a displacement noise-canceled configuration based on a ring-shaped synchronous recycling interferometer. The remarkable feature of this interferometer is that, at certain frequencies, gravitational-wave signals are amplified, while displacement noises are not.

Atsushi Nishizawa; Seiji Kawamura; Masa-aki Sakagami

2008-05-01T23:59:59.000Z

30

A search for gravitational waves associated with the August 2006 timing glitch of the Vela pulsar

The physical mechanisms responsible for pulsar timing glitches are thought to excite quasi-normal mode oscillations in their parent neutron star that couple to gravitational wave emission. In August 2006, a timing glitch was observed in the radio emission of PSR B0833-45, the Vela pulsar. At the time of the glitch, the two co-located Hanford gravitational wave detectors of the Laser Interferometer Gravitational-wave observatory (LIGO) were operational and taking data as part of the fifth LIGO science run (S5). We present the first direct search for the gravitational wave emission associated with oscillations of the fundamental quadrupole mode excited by a pulsar timing glitch. No gravitational wave detection candidate was found. We place Bayesian 90% confidence upper limits of 6.3e-21 to 1.4e-20 on the peak intrinsic strain amplitude of gravitational wave ring-down signals, depending on which spherical harmonic mode is excited. The corresponding range of energy upper limits is 5.0e44 to 1.3e45 erg.

The LIGO Scientific Collaboration; J. Abadie; B. P. Abbott; R. Abbott; R. Adhikari; P. Ajith; B. Allen; G. Allen; E. Amador Ceron; R. S. Amin; S. B. Anderson; W. G. Anderson; M. A. Arain; M. Araya; Y. Aso; S. Aston; P. Aufmuth; C. Aulbert; S. Babak; P. Baker; S. Ballmer; D. Barker; B. Barr; P. Barriga; L. Barsotti; M. A. Barton; I. Bartos; R. Bassiri; M. Bastarrika; B. Behnke; M. Benacquista; M. F. Bennett; J. Betzwieser; P. T. Beyersdorf; I. A. Bilenko; G. Billingsley; R. Biswas; E. Black; J. K. Blackburn; L. Blackburn; D. Blair; B. Bland; O. Bock; T. P. Bodiya; R. Bondarescu; R. Bork; M. Born; S. Bose; P. R. Brady; V. B. Braginsky; J. E. Brau; J. Breyer; D. O. Bridges; M. Brinkmann; M. Britzger; A. F. Brooks; D. A. Brown; S. Buchner; A. Bullington; A. Buonanno; O. Burmeister; R. L. Byer; L. Cadonati; J. Cain; J. B. Camp; J. Cannizzo; K. C. Cannon; J. Cao; C. Capano; L. Cardenas; S. Caudill; M. Cavagliŕ; C. Cepeda; T. Chalermsongsak; E. Chalkley; P. Charlton; S. Chatterji; S. Chelkowski; Y. Chen; N. Christensen; S. S. Y. Chua; C. T. Y. Chung; D. Clark; J. Clark; J. H. Clayton; R. Conte; D. Cook; T. R. C. Corbitt; N. Cornish; D. Coward; D. C. Coyne; J. D. E. Creighton; T. D. Creighton; A. M. Cruise; R. M. Culter; A. Cumming; L. Cunningham; K. Dahl; S. L. Danilishin; K. Danzmann; B. Daudert; G. Davies; E. J. Daw; T. Dayanga; D. DeBra; J. Degallaix; V. Dergachev; R. DeSalvo; S. Dhurandhar; M. Díaz; F. Donovan; K. L. Dooley; E. E. Doomes; R. W. P. Drever; J. Driggers; J. Dueck; I. Duke; J. -C. Dumas; M. Edgar; M. Edwards; A. Effler; P. Ehrens; T. Etzel; M. Evans; T. Evans; S. Fairhurst; Y. Faltas; Y. Fan; D. Fazi; H. Fehrmann; L. S. Finn; K. Flasch; S. Foley; C. Forrest; N. Fotopoulos; M. Frede; M. Frei; Z. Frei; A. Freise; R. Frey; T. T. Fricke; D. Friedrich; P. Fritschel; V. V. Frolov; P. Fulda; M. Fyffe; J. A. Garofoli; S. Ghosh; J. A. Giaime; S. Giampanis; K. D. Giardina; E. Goetz; L. M. Goggin; G. González; S. Goßler; A. Grant; S. Gras; C. Gray; R. J. S. Greenhalgh; A. M. Gretarsson; R. Grosso; H. Grote; S. Grunewald; E. K. Gustafson; R. Gustafson; B. Hage; J. M. Hallam; D. Hammer; G. D. Hammond; C. Hanna; J. Hanson; J. Harms; G. M. Harry; I. W. Harry; E. D. Harstad; K. Haughian; K. Hayama; T. Hayler; J. Heefner; I. S. Heng; A. Heptonstall; M. Hewitson; S. Hild; E. Hirose; D. Hoak; K. A. Hodge; K. Holt; D. J. Hosken; J. Hough; E. Howell; D. Hoyland; B. Hughey; S. Husa; S. H. Huttner; D. R. Ingram; T. Isogai; A. Ivanov; W. W. Johnson; D. I. Jones; G. Jones; R. Jones; L. Ju; P. Kalmus; V. Kalogera; S. Kandhasamy; J. Kanner; E. Katsavounidis; K. Kawabe; S. Kawamura; F. Kawazoe; W. Kells; D. G. Keppel; A. Khalaidovski; F. Y. Khalili; R. Khan; E. Khazanov; H. Kim; P. J. King; J. S. Kissel; S. Klimenko; K. Kokeyama; V. Kondrashov; R. Kopparapu; S. Koranda; D. Kozak; V. Kringel; B. Krishnan; G. Kuehn; J. Kullman; R. Kumar; P. Kwee; P. K. Lam; M. Landry; M. Lang; B. Lantz; N. Lastzka; A. Lazzarini; P. Leaci; M. Lei; N. Leindecker; I. Leonor; H. Lin; P. E. Lindquist; T. B. Littenberg; N. A. Lockerbie; D. Lodhia; M. Lormand; P. Lu; M. Lubinski; A. Lucianetti; H. Lück; A. Lundgren; B. Machenschalk; M. MacInnis; M. Mageswaran; K. Mailand; C. Mak; I. Mandel; V. Mandic; S. Márka; Z. Márka; A. Markosyan; J. Markowitz; E. Maros; I. W. Martin; R. M. Martin; J. N. Marx; K. Mason; F. Matichard; L. Matone; R. A. Matzner; N. Mavalvala; R. McCarthy; D. E. McClelland; S. C. McGuire; G. McIntyre; D. J. A. McKechan; M. Mehmet; A. Melatos; A. C. Melissinos; G. Mendell; D. F. Menéndez; R. A. Mercer; L. Merrill; S. Meshkov; C. Messenger; M. S. Meyer; H. Miao; J. Miller; Y. Mino; S. Mitra; V. P. Mitrofanov; G. Mitselmakher; R. Mittleman; O. Miyakawa; B. Moe; S. D. Mohanty; S. R. P. Mohapatra; G. Moreno; K. Mors; K. Mossavi; C. MowLowry; G. Mueller; H. Müller-Ebhardt; S. Mukherjee; A. Mullavey; J. Munch; P. G. Murray; T. Nash; R. Nawrodt; J. Nelson; G. Newton; E. Nishida; A. Nishizawa; J. O'Dell; B. O'Reilly; R. O'Shaughnessy; E. Ochsner; G. H. Ogin; R. Oldenburg; D. J. Ottaway; R. S. Ottens; H. Overmier; B. J. Owen; A. Page; Y. Pan; C. Pankow; M. A. Papa; P. Patel; D. Pathak; M. Pedraza; L. Pekowsky; S. Penn; C. Peralta; A. Perreca; M. Pickenpack; I. M. Pinto; M. Pitkin; H. J. Pletsch; M. V. Plissi; F. Postiglione; M. Principe; R. Prix; L. Prokhorov; O. Puncken; V. Quetschke; F. J. Raab; D. S. Rabeling; H. Radkins; P. Raffai; Z. Raics; M. Rakhmanov; V. Raymond; C. M. Reed; T. Reed; H. Rehbein; S. Reid; D. H. Reitze; R. Riesen; K. Riles; P. Roberts; N. A. Robertson; C. Robinson; E. L. Robinson; S. Roddy; C. Röver; J. Rollins; J. D. Romano; J. H. Romie; S. Rowan; A. Rüdiger; K. Ryan; S. Sakata; L. Sammut; L. Sancho de la Jordana; V. Sandberg; V. Sannibale; L. Santamaría; G. Santostasi; S. Saraf; P. Sarin; B. S. Sathyaprakash; S. Sato; M. Satterthwaite; P. R. Saulson; R. Savage; R. Schilling

2010-11-05T23:59:59.000Z

31

Gravitational waves from gravitational collapse

Gravitational wave emission from stellar collapse has been studied for nearly four decades. Current state-of-the-art numerical investigations of collapse include those that use progenitors with more realistic angular momentum profiles, properly treat microphysics issues, account for general relativity, and examine non-axisymmetric effects in three dimensions. Such simulations predict that gravitational waves from various phenomena associated with gravitational collapse could be detectable with ground-based and space-based interferometric observatories. This review covers the entire range of stellar collapse sources of gravitational waves: from the accretion induced collapse of a white dwarf through the collapse down to neutron stars or black holes of massive stars to the collapse of supermassive stars.

Fryer, Christopher L [Los Alamos National Laboratory; New, Kimberly C [Los Alamos National Laboratory

2008-01-01T23:59:59.000Z

32

Testing Modified Gravity with Gravitational Wave Astronomy

The emergent area of gravitational wave astronomy promises to provide revolutionary discoveries in the areas of astrophysics, cosmology, and fundamental physics. One of the most exciting possibilities is to use gravitational-wave observations to test alternative theories of gravity. In this contribution we describe how to use observations of extreme-mass-ratio inspirals by the future Laser Interferometer Space Antenna to test a particular class of theories: Chern-Simons modified gravity.

Carlos F. Sopuerta; Nicolas Yunes

2010-10-01T23:59:59.000Z

33

Calibration of the LIGO Gravitational Wave Detectors in the Fifth Science Run

The Laser Interferometer Gravitational Wave Observatory (LIGO) is a network of three detectors built to detect local perturbations in the space-time metric from astrophysical sources. These detectors, two in Hanford, WA and one in Livingston, LA, are power-recycled Fabry-Perot Michelson interferometers. In their fifth science run (S5), between November 2005 and October 2007, these detectors accumulated one year of triple coincident data while operating at their designed sensitivity. In this paper, we describe the calibration of the instruments in the S5 data set, including measurement techniques and uncertainty estimation.

Abadie, J; Abbott, R; M,; Abernathy,; Adams, C; Adhikari, R; Ajith, P; Allen, B; Allen, G; Ceron, E Amador; Amin, R S; Anderson, S B; Anderson, W G; Arain, M A; Araya, M; Aronsson, M; Aso, Y; Aston, S; Atkinson, D E; Aufmuth, P; Aulbert, C; Babak, S; Baker, P; Ballmer, S; Barker, D; Barnum, S; Barr, B; Barriga, P; Barsotti, L; Barton, M A; Bartos, I; Bassiri, R; Bastarrika, M; Bauchrowitz, J; Behnke, B; Benacquista, M; Bertolini, A; Betzwieser, J; Beveridge, N; Beyersdorf, P T; Bilenko, I A; Billingsley, G; Birch, J; Biswas, R; Black, E; Blackburn, J K; Blackburn, L; Blair, D; Bland, B; Bock, O; Bodiya, T P; Bondarescu, R; Bork, R; Born, M; Bose, S; Boyle, M; Brady, P R; Braginsky, V B; Brau, J E; Breyer, J; Bridges, D O; Brinkmann, M; Britzger, M; Brooks, A F; Brown, D A; Buonanno, A; Burguet--Castell, J; Burmeister, O; Byer, R L; Cadonati, L; Camp, J B; Campsie, P; Cannizzo, J; Cannon, K C; Cao, J; Capano, C; Caride, S; Caudill, S; Cavagliŕ, M; Cepeda, C; Chalermsongsak, T; Chalkley, E; Charlton, P; Chelkowski, S; Chen, Y; Christensen, N; Chua, S S Y; Chung, C T Y; Clark, D; Clark, J; Clayton, J H; Conte, R; Cook, D; Corbitt, T R; Cornish, N; Costa, C A; Coward, D; Coyne, D C; Creighton, J D E; Creighton, T D; Cruise, A M; Culter, R M; Cumming, A; Cunningham, L; Dahl, K; Danilishin, S L; Dannenberg, R; Danzmann, K; Das, K; Daudert, B; Davies, G; Davis, A; Daw, E J; Dayanga, T; DeBra, D; Degallaix, J; Dergachev, V; DeRosa, R; DeSalvo, R; Devanka, P; Dhurandhar, S; Di Palma, I; Díaz, M; Donovan, F; Dooley, K L; Doomes, E E; Dorsher, S; Douglas, E S D; Drever, R W P; Driggers, J C; Dueck, J; Dumas, J -C; Eberle, T; Edgar, M; Edwards, M; Effler, A; Ehrens, P; Engel, R; Etzel, T; Evans, M; Evans, T; Fairhurst, S; Fan, Y; Farr, B F; Fazi, D; Fehrmann, H; Feldbaum, D; Finn, L S; Flanigan, M; Flasch, K; Foley, S; Forrest, C; Forsi, E; Fotopoulos, N; Frede, M; Frei, M; Frei, Z; Freise, A; Frey, R; Fricke, T T; Friedrich, D; Fritschel, P; Frolov, V V; Fulda, P; Fyffe, M; Garofoli, J A; Gholami, I; Ghosh, S; Giaime, J A; Giampanis, S; Giardina, K D; Gill, C; Goetz, E; Goggin, L M; González, G; Gorodetsky, M L; Goßler, S; Graef, C; Grant, A; Gras, S; Gray, C; Greenhalgh, R J S; Gretarsson, A M; Grosso, R; Grote, H; Grunewald, S; Gustafson, E K; Gustafson, R; Hage, B; Hall, P; Hallam, J M; Hammer, D; Hammond, G; Hanks, J; Hanna, C; Hanson, J; Harms, J; Harry, G M; Harry, I W; Harstad, E D; Haughian, K; Hayama, K; Heefner, J; Heng, I S; Heptonstall, A; Hewitson, M; Hild, S; Hirose, E; Hoak, D; Hodge, K A; Holt, K; Hosken, D J; Hough, J; Howell, E; Hoyland, D; Hughey, B; Husa, S; Huttner, S H; Huynh--Dinh, T; Ingram, D R; Inta, R; Isogai, T; Ivanov, A; Johnson, W W; Jones, D I; Jones, G; Jones, R; Ju, L; Kalmus, P; Kalogera, V; Kandhasamy, S; Kanner, J; Katsavounidis, E; Kawabe, K; Kawamura, S; Kawazoe, F; Kells, W; Keppel, D G; Khalaidovski, A; Khalili, F Y; Khazanov, E A; Kim, H; King, P J; Kinzel, D L; Kissel, J S; Klimenko, S; Kondrashov, V; Kopparapu, R; Koranda, S; Kozak, D; Krause, T; Kringel, V; Krishnamurthy, S; Krishnan, B; Kuehn, G; Kullman, J; Kumar, R; Kwee, P; Landry, M; Lang, M; Lantz, B; Lastzka, N; Lazzarini, A; Leaci, P; Leong, J; Leonor, I; Li, J; Lin, H; Lindquist, P E; Lockerbie, N A; Lodhia, D; Lormand, M; Lu, P; Luan, J; Lubinski, M; Lucianetti, A; Lück, H; Lundgren, A; Machenschalk, B; MacInnis, M; Mageswaran, M; Mailand, K; Mak, C; Mandel, I; Mandic, V; Márka, S; Márka, Z; Maros, E; Martin, I W; Martin, R M; Marx, J N; Mason, K; Matichard, F; Matone, L; Matzner, R A; Mavalvala, N; McCarthy, R; McClelland, D E; McGuire, S C; McIntyre, G; McIvor, G; McKechan, D J A; Meadors, G; Mehmet, M; Meier, T; Melatos, A; Melissinos, A C; Mendell, G; Menéndez, D F; Mercer, R A; Merill, L; Meshkov, S; Messenger, C; Meyer, M S; Miao, H; Miller, J; Mino, Y; Mitra, S; Mitrofanov, V P; Mitselmakher, G; Mittleman, R; Moe, B; Mohanty, S D; Mohapatra, S R P; Moraru, D; Moreno, G; Morioka, T; Mors, K; Mossavi, K; MowLowry, C; Mueller, G; Mukherjee, S; Mullavey, A; Müller-Ebhardt, H; Munch, J; Murray, P G; Nash, T; Nawrodt, R; Nelson, J; Newton, G; Nishizawa, A; Nolting, D; Ochsner, E; O'Dell, J; Ogin, G H; Oldenburg, R G; O'Reilly, B; O'Shaughnessy, R; Osthelder, C; Ottaway, D J; Ottens, R S; Overmier, H; Owen, B J; Page, A; Pan, Y; Pankow, C; Papa, M A; Pareja, M; Patel, P; Pedraza, M; Pekowsky, L; Penn, S; Peralta, C; Perreca, A; Pickenpack, M; Pinto, I M; Pitkin, M; Pletsch, H J; Plissi, M V; Postiglione, F; Predoi, V; Price, L R; Prijatelj, M; Principe, M; Prix, R; Prokhorov, L; Puncken, O; Quetschke, V; Raab, F J; Radke, T; Radkins, H; Raffai, P; Rakhmanov, M; Rankins, B; Raymond, V; Reed, C M; Reed, T; Reid, S; Reitze, D H; Riesen, R; Riles, K; Roberts, P; Robertson, N A; Robinson, C; Robinson, E L; Roddy, S; Röver, C; Rollins, J; Romano, J D; Romie, J H; Rowan, S; Rüdiger, A; Ryan, K; Sakata, S; Sakosky, M

2010-01-01T23:59:59.000Z

34

Calibration of the LIGO Gravitational Wave Detectors in the Fifth Science Run

The Laser Interferometer Gravitational Wave Observatory (LIGO) is a network of three detectors built to detect local perturbations in the space-time metric from astrophysical sources. These detectors, two in Hanford, WA and one in Livingston, LA, are power-recycled Fabry-Perot Michelson interferometers. In their fifth science run (S5), between November 2005 and October 2007, these detectors accumulated one year of triple coincident data while operating at their designed sensitivity. In this paper, we describe the calibration of the instruments in the S5 data set, including measurement techniques and uncertainty estimation.

LIGO Scientific Collaboration; J. Abadie; B. P. Abbott; R. Abbott; M; Abernathy; C. Adams; R. Adhikari; P. Ajith; B. Allen; G. Allen; E. Amador Ceron; R. S. Amin; S. B. Anderson; W. G. Anderson; M. A. Arain; M. Araya; M. Aronsson; Y. Aso; S. Aston; D. E. Atkinson; P. Aufmuth; C. Aulbert; S. Babak; P. Baker; S. Ballmer; D. Barker; S. Barnum; B. Barr; P. Barriga; L. Barsotti; M. A. Barton; I. Bartos; R. Bassiri; M. Bastarrika; J. Bauchrowitz; B. Behnke; M. Benacquista; A. Bertolini; J. Betzwieser; N. Beveridge; P. T. Beyersdorf; I. A. Bilenko; G. Billingsley; J. Birch; R. Biswas; E. Black; J. K. Blackburn; L. Blackburn; D. Blair; B. Bland; O. Bock; T. P. Bodiya; R. Bondarescu; R. Bork; M. Born; S. Bose; M. Boyle; P. R. Brady; V. B. Braginsky; J. E. Brau; J. Breyer; D. O. Bridges; M. Brinkmann; M. Britzger; A. F. Brooks; D. A. Brown; A. Buonanno; J. Burguet--Castell; O. Burmeister; R. L. Byer; L. Cadonati; J. B. Camp; P. Campsie; J. Cannizzo; K. C. Cannon; J. Cao; C. Capano; S. Caride; S. Caudill; M. Cavagliŕ; C. Cepeda; T. Chalermsongsak; E. Chalkley; P. Charlton; S. Chelkowski; Y. Chen; N. Christensen; S. S. Y. Chua; C. T. Y. Chung; D. Clark; J. Clark; J. H. Clayton; R. Conte; D. Cook; T. R. Corbitt; N. Cornish; C. A. Costa; D. Coward; D. C. Coyne; J. D. E. Creighton; T. D. Creighton; A. M. Cruise; R. M. Culter; A. Cumming; L. Cunningham; K. Dahl; S. L. Danilishin; R. Dannenberg; K. Danzmann; K. Das; B. Daudert; G. Davies; A. Davis; E. J. Daw; T. Dayanga; D. DeBra; J. Degallaix; V. Dergachev; R. DeRosa; R. DeSalvo; P. Devanka; S. Dhurandhar; I. Di Palma; M. Díaz; F. Donovan; K. L. Dooley; E. E. Doomes; S. Dorsher; E. S. D. Douglas; R. W. P. Drever; J. C. Driggers; J. Dueck; J. -C. Dumas; T. Eberle; M. Edgar; M. Edwards; A. Effler; P. Ehrens; R. Engel; T. Etzel; M. Evans; T. Evans; S. Fairhurst; Y. Fan; B. F. Farr; D. Fazi; H. Fehrmann; D. Feldbaum; L. S. Finn; M. Flanigan; K. Flasch; S. Foley; C. Forrest; E. Forsi; N. Fotopoulos; M. Frede; M. Frei; Z. Frei; A. Freise; R. Frey; T. T. Fricke; D. Friedrich; P. Fritschel; V. V. Frolov; P. Fulda; M. Fyffe; J. A. Garofoli; I. Gholami; S. Ghosh; J. A. Giaime; S. Giampanis; K. D. Giardina; C. Gill; E. Goetz; L. M. Goggin; G. González; M. L. Gorodetsky; S. Goßler; C. Graef; A. Grant; S. Gras; C. Gray; R. J. S. Greenhalgh; A. M. Gretarsson; R. Grosso; H. Grote; S. Grunewald; E. K. Gustafson; R. Gustafson; B. Hage; P. Hall; J. M. Hallam; D. Hammer; G. Hammond; J. Hanks; C. Hanna; J. Hanson; J. Harms; G. M. Harry; I. W. Harry; E. D. Harstad; K. Haughian; K. Hayama; J. Heefner; I. S. Heng; A. Heptonstall; M. Hewitson; S. Hild; E. Hirose; D. Hoak; K. A. Hodge; K. Holt; D. J. Hosken; J. Hough; E. Howell; D. Hoyland; B. Hughey; S. Husa; S. H. Huttner; T. Huynh--Dinh; D. R. Ingram; R. Inta; T. Isogai; A. Ivanov; W. W. Johnson; D. I. Jones; G. Jones; R. Jones; L. Ju; P. Kalmus; V. Kalogera; S. Kandhasamy; J. Kanner; E. Katsavounidis; K. Kawabe; S. Kawamura; F. Kawazoe; W. Kells; D. G. Keppel; A. Khalaidovski; F. Y. Khalili; E. A. Khazanov; H. Kim; P. J. King; D. L. Kinzel; J. S. Kissel; S. Klimenko; V. Kondrashov; R. Kopparapu; S. Koranda; D. Kozak; T. Krause; V. Kringel; S. Krishnamurthy; B. Krishnan; G. Kuehn; J. Kullman; R. Kumar; P. Kwee; M. Landry; M. Lang; B. Lantz; N. Lastzka; A. Lazzarini; P. Leaci; J. Leong; I. Leonor; J. Li; H. Lin; P. E. Lindquist; N. A. Lockerbie; D. Lodhia; M. Lormand; P. Lu; J. Luan; M. Lubinski; A. Lucianetti; H. Lück; A. Lundgren; B. Machenschalk; M. MacInnis; M. Mageswaran; K. Mailand; C. Mak; I. Mandel; V. Mandic; S. Márka; Z. Márka; E. Maros; I. W. Martin; R. M. Martin; J. N. Marx; K. Mason; F. Matichard; L. Matone; R. A. Matzner; N. Mavalvala; R. McCarthy; D. E. McClelland; S. C. McGuire; G. McIntyre; G. McIvor; D. J. A. McKechan; G. Meadors; M. Mehmet; T. Meier; A. Melatos; A. C. Melissinos; G. Mendell; D. F. Menéndez; R. A. Mercer; L. Merill; S. Meshkov; C. Messenger; M. S. Meyer; H. Miao; J. Miller; Y. Mino; S. Mitra; V. P. Mitrofanov; G. Mitselmakher; R. Mittleman; B. Moe; S. D. Mohanty; S. R. P. Mohapatra; D. Moraru; G. Moreno; T. Morioka; K. Mors; K. Mossavi; C. MowLowry; G. Mueller; S. Mukherjee; A. Mullavey; H. Müller-Ebhardt; J. Munch; P. G. Murray; T. Nash; R. Nawrodt; J. Nelson; G. Newton; A. Nishizawa; D. Nolting; E. Ochsner; J. O'Dell; G. H. Ogin; R. G. Oldenburg; B. O'Reilly; R. O'Shaughnessy; C. Osthelder; D. J. Ottaway; R. S. Ottens; H. Overmier; B. J. Owen; A. Page; Y. Pan; C. Pankow; M. A. Papa; M. Pareja; P. Patel; M. Pedraza; L. Pekowsky; S. Penn; C. Peralta; A. Perreca; M. Pickenpack; I. M. Pinto; M. Pitkin; H. J. Pletsch; M. V. Plissi; F. Postiglione; V. Predoi; L. R. Price; M. Prijatelj; M. Principe; R. Prix; L. Prokhorov; O. Puncken; V. Quetschke; F. J. Raab; T. Radke; H. Radkins; P. Raffai; M. Rakhmanov; B. Rankins; V. Raymond; C. M. Reed; T. Reed; S. Reid; D. H. Reitze; R. Riesen

2010-07-22T23:59:59.000Z

35

Smooth sandwich gravitational waves

Gravitational waves which are smooth and contain two asymptotically flat regions are constructed from the homogeneous pp-waves vacuum solution. Motion of free test particles is calculated explicitly and the limit to an impulsive wave is also considered.

J. Podolsky

1998-07-16T23:59:59.000Z

36

Environmental Effects for Gravitational-wave Astrophysics

The upcoming detection of gravitational waves by terrestrial interferometers will usher in the era of gravitational-wave astronomy. This will be particularly true when space-based detectors will come of age and measure the mass and spin of massive black holes with exquisite precision and up to very high redshifts, thus allowing for better understanding of the symbiotic evolution of black holes with galaxies, and for high-precision tests of General Relativity in strong-field, highly-dynamical regimes. Such ambitious goals require that astrophysical environmental pollution of gravitational-wave signals be constrained to negligible levels, so that neither detection nor estimation of the source parameters are significantly affected. Here, we consider the main sources for space-based detectors -the inspiral, merger and ringdown of massive black-hole binaries and extreme mass-ratio inspirals- and account for various effects on their gravitational waveforms, including electromagnetic fields, cosmological evolution, ...

Barausse, Enrico; Pani, Paolo

2014-01-01T23:59:59.000Z

37

We have performed a search for bursts of gravitational waves associated with the very bright Gamma Ray Burst GRB030329, using the two detectors at the LIGO Hanford Observatory. Our search covered the most sensitive frequency range of the LIGO detectors (approximately 80-2048 Hz), and we specifically targeted signals shorter than {approx_equal}150 ms. Our search algorithm looks for excess correlated power between the two interferometers and thus makes minimal assumptions about the gravitational waveform. We observed no candidates with gravitational wave signal strength larger than a pre-determined threshold. We report frequency dependent upper limits on the strength of the gravitational waves associated with GRB030329. Near the most sensitive frequency region, around {approx_equal}250 Hz, our root-sum-square (RSS) gravitational wave strain sensitivity for optimally polarized bursts was better than h{sub RSS} {approx_equal} 6 x 10{sup -21} Hz{sup -1/2}. Our result is comparable to the best published results searching for association between gravitational waves and GRBs.

Abbott, B.; Abbott, R.; Adhikari, R.; Ageev, A.; Allen, B.; Amin, R.; Anderson, S.B.; Anderson, W.G.; Araya, M.; Armandula, H.; Ashley, M.; Asiri, F.; Aufmuth, P.; Aulbert, C.; Babak, S.; Balasubramanian, R.; Ballmer, S.; Barish, B.C.; Barker, C.; Barker, D.; Barnes, M.; /Potsdam, Max Planck Inst. /Hannover, Max Planck Inst. Grav. /Australian

2005-01-01T23:59:59.000Z

38

The use of squeezed states and balanced homodyne for detecting gravitational waves

The possibility of using squeezed states and balanced homodyne detection of gravitational waves is discussed. It is shown that the quantum noise due to high laser intensities in Michelson interferometer for gravitational waves detection can be reduced by sending squeezed vacuum states to the 'dark' port of the interferometer. The present analysis describes photon statistics measurements effects related to quadrature balanced homodyne detection showing the advantage of using this scheme for detecting gravitational waves.

Y. Ben-Aryeh

2010-10-05T23:59:59.000Z

39

Environmental Effects for Gravitational-wave Astrophysics

The upcoming detection of gravitational waves by terrestrial interferometers will usher in the era of gravitational-wave astronomy. This will be particularly true when space-based detectors will come of age and measure the mass and spin of massive black holes with exquisite precision and up to very high redshifts, thus allowing for better understanding of the symbiotic evolution of black holes with galaxies, and for high-precision tests of General Relativity in strong-field, highly dynamical regimes. Such ambitious goals require that astrophysical environmental pollution of gravitational-wave signals be constrained to negligible levels, so that neither detection nor estimation of the source parameters are significantly affected. Here, we consider the main sources for space-based detectors -- the inspiral, merger and ringdown of massive black-hole binaries and extreme mass-ratio inspirals -- and account for various effects on their gravitational waveforms, including electromagnetic fields, cosmological evolution, accretion disks, dark matter, "firewalls" and possible deviations from General Relativity. We discover that the black-hole quasinormal modes are sharply different in the presence of matter, but the ringdown signal observed by interferometers is typically unaffected. The effect of accretion disks and dark matter depends critically on their geometry and density profile, but is negligible for most sources, except for few special extreme mass-ratio inspirals. Electromagnetic fields and cosmological effects are always negligible. We finally explore the implications of our findings for proposed tests of General Relativity with gravitational waves, and conclude that environmental effects will not prevent the development of precision gravitational-wave astronomy.

Enrico Barausse; Vitor Cardoso; Paolo Pani

2015-01-07T23:59:59.000Z

40

Gravitational waves from rapidly rotating neutron stars

Rapidly rotating neutron stars in Low Mass X-ray Binaries have been proposed as an interesting source of gravitational waves. In this chapter we present estimates of the gravitational wave emission for various scenarios, given the (electromagnetically) observed characteristics of these systems. First of all we focus on the r-mode instability and show that a 'minimal' neutron star model (which does not incorporate exotica in the core, dynamically important magnetic fields or superfluid degrees of freedom), is not consistent with observations. We then present estimates of both thermally induced and magnetically sustained mountains in the crust. In general magnetic mountains are likely to be detectable only if the buried magnetic field of the star is of the order of $B\\approx 10^{12}$ G. In the thermal mountain case we find that gravitational wave emission from persistent systems may be detected by ground based interferometers. Finally we re-asses the idea that gravitational wave emission may be balancing the accretion torque in these systems, and show that in most cases the disc/magnetosphere interaction can account for the observed spin periods.

Brynmor Haskell; Nils Andersson; Caroline D`Angelo; Nathalie Degenaar; Kostas Glampedakis; Wynn C. G. Ho; Paul D. Lasky; Andrew Melatos; Manuel Oppenoorth; Alessandro Patruno; Maxim Priymak

2014-07-31T23:59:59.000Z

While these samples are representative of the content of NLE

they are not comprehensive nor are they the most current set.

We encourage you to perform a real-time search of NLE

to obtain the most current and comprehensive results.

41

Gravitational wave astronomy - astronomy of the 21st century

An enigmatic prediction of Einstein's general theory of relativity is gravitational waves. With the observed decay in the orbit of the Hulse-Taylor binary pulsar agreeing within a fraction of a percent with the theoretically computed decay from Einstein's theory, the existence of gravitational waves was firmly established. Currently there is a worldwide effort to detect gravitational waves with interferometric gravitational wave observatories or detectors and several such detectors have been built or being built. The initial detectors have reached their design sensitivities and now the effort is on to construct advanced detectors which are expected to detect gravitational waves from astrophysical sources. The era of gravitational wave astronomy has arrived. This article describes the worldwide effort which includes the effort on the Indian front - the IndIGO project -, the principle underlying interferometric detectors both on ground and in space, the principal noise sources that plague such detectors, the astrophysical sources of gravitational waves that one expects to detect by these detectors and some glimpse of the data analysis methods involved in extracting the very weak gravitational wave signals from detector noise.

S. V. Dhurandhar

2011-04-15T23:59:59.000Z

42

The direct detection of gravitational waves with upcoming second-generation gravitational wave observatories such as Advanced LIGO and Advanced Virgo will allow us to probe the genuinely strong-field dynamics of general ...

Agathos, M.

43

Momentum Imparted by Gravitational Waves

We calculate momentum imparted by colliding gravitational waves in a closed Friedmann Robertson-Walker background and also by gravitational waves with toroidal wavefronts using an operational procedure. The results obtained for toroidal wavefronts are well behaved and reduce to the spherical wavefronts for a special choice.

M. Sharif

2003-04-04T23:59:59.000Z

44

Primordial Gravitational Waves Enhancement

We reconsider the enhancement of primordial gravitational waves that arises from a quantum gravitational model of inflation. A distinctive feature of this model is that the end of inflation witnesses a brief phase during which the Hubble parameter oscillates in sign, changing the usual Hubble friction to anti-friction. An earlier analysis of this model was based on numerically evolving the graviton mode functions after guessing their initial conditions near the end of inflation. The current study is based on an equation which directly evolves the normalized square of the magnitude. We are also able to make a very reliable estimate for the initial condition using a rapidly converging expansion for the sub-horizon regime. Results are obtained for the energy density per logarithmic wave number as a fraction of the critical density. These results exhibit how the enhanced signal depends upon the number of oscillatory periods; they also show the resonant effects associated with particular wave numbers.

Maria G. Romania; N. C. Tsamis; R. P. Woodard

2011-08-08T23:59:59.000Z

45

The Laser Interferometer Gravitational Observatory (LIGO) has recently reached the end of its fifth science run (S5), having collected more than a year worth of data. Analysis of the data is still ongoing but a positive detection of gravitational waves, while possible, is not realistically expected for most likely sources. This is particularly true for what concerns gravitational waves from known pulsars. In fact, even under the most optimistic (and not very realistic) assumption that all the pulsar's observed spin-down is due to gravitational waves, the gravitational wave strain at earth from all the known isolated pulsars (with the only notable exception of the Crab pulsar) would not be strong enough to be detectable by existing detectors. By August 2006, LIGO had produced enough data for a coherent integration capable to extract signal from noise that was weaker than the one expected from the Crab pulsar's spin-down limit. No signal was detected, but beating the spin-down limit is a considerable achievement for the LIGO Scientific Collaboration (LSC). It is customary to translate the upper limit on strain from a pulsar into a more astrophysically significant upper limit on ellipticity. Once the spin-down limit has been beaten, it is possible to release the constraint that all the spin-down is due to gravitational wave emission. A more complete model with diverse braking mechanisms can be used to set limits on several astrophysical parameters of the pulsar. This paper shows possible values of such parameters for the Crab pulsar given the current limit on gravitational waves from this neutron star.

Giovanni Santostasi

2008-07-16T23:59:59.000Z

46

The Magdalena Ridge Observatory interferometer: 2014 status update

the full complement of 10 telescope beams of the MROI. The design enables ICoNN to detect and track the interferometer fringe phase at either the H or Ks infrared bandpasses for any distribution of neighboring telescopes. It is a dedicated fringe... -mechanical stability even when tested in a university laboratory environment with no temperature or vibration control. Previous proceedings (Jurgenson et al. 2008 and McCracken et al. 2012, Santoro et al. 2012) have detailed the design and plans for laboratory...

Creech-Eakman, M. J.; Romero, V.; Payne, I.; Haniff, C. A.; Buscher, D. F.; Dahl, C.; Farris, A.; Fisher, M.; Jurgenson, C.; Klinglesmith, D.; McCracken, T.; Napolitano, M.; Olivares, A.; Riker, J.; Rochelle, S.; Salcido, C.; Santoro, F.; Schmidt, L.; Selina, R.; Seneta, E. B.; Shtromberg, A.; Sun, X.; Wilson, D. M. A.; Young, J. S.

2014-07-24T23:59:59.000Z

47

Gravitational waves: a foundational review

The standard linear approach to the gravitational waves theory is critically reviewed. Contrary to the prevalent understanding, it is pointed out that this theory contains many conceptual and technical obscure issues that require further analysis.

J. G. Pereira

2013-07-25T23:59:59.000Z

48

Mother templates for gravitational wave chirps

Templates used in a search for binary black holes and neutron stars in gravitational wave interferometer data will have to be computed on-line since the computational storage and retrieval costs for the template bank are too expensive. The conventional dimensionless variable $T=(c^3/Gm)t,$ where $m$ is the total mass of a binary, in the time-domain and a not-so-conventional velocity-like variable $v=(\\pi Gm f)^{1/3}$ in the Fourier-domain, render the phasing of the waves independent of the total mass of the system enabling the construction of {\\it mother templates} that depend only on the mass ratio of a black hole binary. Use of such mother templates in a template bank will bring about a reduction in computational costs up to a factor of 10 and a saving on storage by a factor of 100.

B. S. Sathyaprakash

2000-10-11T23:59:59.000Z

49

Nanogap Transducer for Broadband Gravitational Wave Detection

By changing from a resonant multimode paradigm to a free mass paradigm for transducers in resonant mass gravitational wave detection, an array of six spheres can achieve a sensitivity response curve competitive with interferometers, being as sensitive as GEO600 and TAMA300 in the 3 to 6 kHz band and more sensitive than LIGO for 50 percent of the 6 to 10 kHz band. We study how to assemble a klystron resonant cavity that has a 1 nm gap by understanding the stability of the forces applied at it (Casimir force, elastic force, weight). This approach has additional benefits. First, due to the relatively inexpensive nature of this technology (around US$ 1 million), it is accessible to a broader part of the world scientific community. Additionally, spherical resonant mass detectors have the ability to discern both the direction and polarization resolutions.

Guilherme L. Pimentel; Odylio D. Aguiar; Michael E. Tobar; Joaquim J. Barroso; Rubens de M. Marinho

2009-10-06T23:59:59.000Z

50

Gravitational waves from merging compact binaries

Largely motivated by the development of highly sensitive gravitational-wave detectors, our understanding of merging compact binaries and the gravitational waves they generate has improved dramatically in recent years. ...

Hughes, Scott A.

51

Constraining the gravitational wave energy density of the Universe using Earth's ring

The search for gravitational waves is one of today's major scientific endeavors. A gravitational wave can interact with matter by exciting vibrations of elastic bodies. Earth itself is a large elastic body whose so-called normal-mode oscillations ring up when a gravitational wave passes. Therefore, precise measurement of vibration amplitudes can be used to search for the elusive gravitational-wave signals. Earth's free oscillations that can be observed after high-magnitude earthquakes have been studied extensively with gravimeters and low-frequency seismometers over many decades leading to invaluable insight into Earth's structure. Making use of our detailed understanding of Earth's normal modes, numerical models are employed for the first time to accurately calculate Earth's gravitational-wave response, and thereby turn a network of sensors that so far has served to improve our understanding of Earth, into an astrophysical observatory exploring our Universe. In this article, we constrain the energy density of gravitational waves to values in the range 0.035 - 0.15 normalized by the critical energy density of the Universe at frequencies between 0.3mHz and 5mHz, using 10 years of data from the gravimeter network of the Global Geodynamics Project that continuously monitors Earth's oscillations. This work is the first step towards a systematic investigation of the sensitivity of gravimeter networks to gravitational waves. Further advance in gravimeter technology could improve sensitivity of these networks and possibly lead to gravitational-wave detection.

Michael Coughlin; Jan Harms

2014-06-04T23:59:59.000Z

52

Gravitational wave radiometry: Mapping a stochastic gravitational wave background

The problem of the detection and mapping of a stochastic gravitational wave background (SGWB), either cosmological or astrophysical, bears a strong semblance to the analysis of the cosmic microwave background (CMB) anisotropy and polarization, which too is a stochastic field, statistically described in terms of its correlation properties. An astrophysical gravitational wave background (AGWB) will likely arise from an incoherent superposition of unmodelled and/or unresolved sources and cosmological gravitational wave backgrounds (CGWB) are also predicted in certain scenarios. The basic statistic we use is the cross correlation between the data from a pair of detectors. In order to ''point'' the pair of detectors at different locations one must suitably delay the signal by the amount it takes for the gravitational waves (GW) to travel to both detectors corresponding to a source direction. Then the raw (observed) sky map of the SGWB is the signal convolved with a beam response function that varies with location in the sky. We first present a thorough analytic understanding of the structure of the beam response function using an analytic approach employing the stationary phase approximation. The true sky map is obtained by numerically deconvolving the beam function in the integral (convolution) equation. We adopt the maximum likelihood framework to estimate the true sky map using the conjugate gradient method that has been successfully used in the broadly similar, well-studied CMB map-making problem. We numerically implement and demonstrate the method on signal generated by simulated (unpolarized) SGWB for the GW radiometer consisting of the LIGO pair of detectors at Hanford and Livingston. We include 'realistic' additive Gaussian noise in each data stream based on the LIGO-I noise power spectral density. The extension of the method to multiple baselines and polarized GWB is outlined. In the near future the network of GW detectors, including the Advanced LIGO and Virgo detectors that will be sensitive to sources within a thousand times larger spatial volume, could provide promising data sets for GW radiometry.

Mitra, Sanjit [Inter-University Centre for Astronomy and Astrophysics, Post Bag 4, Ganeshkhind, Pune 411007 (India); Observatoire de la Cote d'Azur, BP 4229, 06304 Nice Cedex 4 (France); Dhurandhar, Sanjeev; Souradeep, Tarun [Inter-University Centre for Astronomy and Astrophysics, Post Bag 4, Ganeshkhind, Pune 411007 (India); Lazzarini, Albert; Mandic, Vuk; Ballmer, Stefan [LIGO Laboratory, California Institute of Technology, MS 18-34, Pasadena, California 91125 (United States); Bose, Sukanta [Department of Physics, Washington State University, Pullman, Washington 99164-2814 (United States)

2008-02-15T23:59:59.000Z

53

Design of a speed meter interferometer proof-of-principle experiment

The second generation of large scale interferometric gravitational wave detectors will be limited by quantum noise over a wide frequency range in their detection band. Further sensitivity improvements for future upgrades or new detectors beyond the second generation motivate the development of measurement schemes to mitigate the impact of quantum noise in these instruments. Two strands of development are being pursued to reach this goal, focusing both on modifications of the well-established Michelson detector configuration and development of different detector topologies. In this paper, we present the design of the world's first Sagnac speed meter interferometer which is currently being constructed at the University of Glasgow. With this proof-of-principle experiment we aim to demonstrate the theoretically predicted lower quantum noise in a Sagnac interferometer compared to an equivalent Michelson interferometer, to qualify Sagnac speed meters for further research towards an implementation in a future generation large scale gravitational wave detector, such as the planned Einstein Telescope observatory.

C. Gräf; B. W. Barr; A. S. Bell; F. Campbell; A. V. Cumming; S. L. Danilishin; N. A. Gordon; G. D. Hammond; J. Hennig; E. A. Houston; S. H. Huttner; R. A. Jones; S. S. Leavey; H. Lück; J. Macarthur; M. Marwick; S. Rigby; R. Schilling; B. Sorazu; A. Spencer; S. Steinlechner; K. A. Strain; S. Hild

2014-09-11T23:59:59.000Z

54

Gravitational waves from perturbed stars

Non radial oscillations of neutron stars are associated with the emission of gravitational waves. The characteristic frequencies of these oscillations can be computed using the theory of stellar perturbations, and they are shown to carry detailed information on the internal structure of the emitting source. Moreover, they appear to be encoded in various radiative processes, as for instance in the tail of the giant flares of Soft Gamma Repeaters. Thus, their determination is central to the theory of stellar perturbation. A viable approach to the problem consists in formulating this theory as a problem of resonant scattering of gravitational waves incident on the potential barrier generated by the spacetime curvature. This approach discloses some unexpected correspondences between the theory of stellar perturbations and the theory of quantum mechanics, and allows us to predict new relativistic effects.

Valeria Ferrari

2011-05-09T23:59:59.000Z

55

Progress towards Gravitational Wave Astronomy

I will review the most recent and interesting results from gravitational wave detection experiments, concentrating on recent results from the LIGO Scientific Collaboration (LSC). I will outline the methodologies utilized in the searches, explain what can be said in the case of a null result, what quantities may be constrained. I will compare these results with prior expectations and discuss their significance. As I go along I will outline the prospects for future improvements.

M. Alessandra Papa

2008-02-07T23:59:59.000Z

56

Double optical spring enhancement for gravitational wave detectors

Currently planned second-generation gravitational-wave laser interferometers such as Advanced LIGO exploit the extensively investigated signal-recycling (SR) technique. Candidate Advanced LIGO configurations are usually designed to have two resonances within the detection band, around which the sensitivity is enhanced: a stable optical resonance and an unstable optomechanical resonance - which is upshifted from the pendulum frequency due to the so-called optical-spring effect. Alternative to a feedback control system, we propose an all-optical stabilization scheme, in which a second optical spring is employed, and the test mass is trapped by a stable ponderomotive potential well induced by two carrier light fields whose detunings have opposite signs. The double optical spring also brings additional flexibility in re-shaping the noise spectral density and optimizing toward specific gravitational-wave sources. The presented scheme can be extended easily to a multi-optical-spring system that allows further optimization.

Henning Rehbein; Helge Mueller-Ebhardt; Kentaro Somiya; Stefan L. Danilishin; Roman Schnabel; Karsten Danzmann; Yanbei Chen

2008-05-20T23:59:59.000Z

57

The Nonlinear Essence of Gravitational Waves

A critical review of gravitational wave theory is made. It is pointed out that the usual linear approach to the gravitational wave theory is neither conceptually consistent nor mathematically justified. Relying upon that analysis it is then argued that -- analogously to a Yang-Mills propagating field, which must be nonlinear to carry its gauge charge -- a gravitational wave must necessarily be nonlinear to transport its own charge -- that is, energy-momentum.

R. Aldrovandi; J. G. Pereira; K. H. Vu

2007-09-11T23:59:59.000Z

58

Geodesic deviation and gravitational waves

The detection of gravitational waves based on the geodesic deviation equation is discussed. In particular, it is shown that the only non-vanishing components of the wave field in the conventional traceless-transverse gauge in linearized general relativity do not enter the geodesic deviation equation, and therefore, apparently, no effect is predicted by that equation in that specific gauge. The reason is traced back to the fact that the geodesic deviation equation is written in terms of a coordinate distance, which is not a directly measurable quantity. On the other hand, in the proper Lorentz frame of the detector, the conventional result described in standard textbooks holds.

M. Leclerc

2006-05-24T23:59:59.000Z

59

Displacement-noise-free resonant speed meter for gravitational-wave detection

We demonstrate that speedmeter, based on double pumped resonant Sagnac interferometer, can be used as a displacement noise free gravitational-wave (GW) detector. The displacement noise of cavity mirrors can be completely excluded through a proper linear combination of the output signals. We show that in low-frequency region the obtained displacement-noise-free response signal is stronger than the one in previously proposed displacement noise free interferometers.

Sergey P. Vyatchanin

2008-08-26T23:59:59.000Z

60

This paper describes the design of, and results from, a calibration system for optical linear displacement (shadow) sensors. The shadow sensors were designed to detect “Violin-Mode” (VM) resonances in the 0.4 mm diameter silica fibre suspensions of the test masses/mirrors of Advanced Laser Interferometer Gravitational Wave Observatory gravitational wave interferometers. Each sensor illuminated the fibre under test, so as to cast its narrow shadow onto a “synthesized split photodiode” detector, the shadow falling over adjacent edges of the paired photodiodes. The apparatus described here translated a vertically orientated silica test fibre horizontally through a collimated Near InfraRed illuminating beam, whilst simultaneously capturing the separate DC “shadow notch” outputs from each of the paired split photodiode detectors. As the ratio of AC to DC photocurrent sensitivities to displacement was known, a calibration of the DC response to quasi-static shadow displacement allowed the required AC sensitivity to vibrational displacement to be found. Special techniques are described for generating the required constant scan rate for the test fibre using a DC motor-driven stage, for removing “jitter” at such low translation rates from a linear magnetic encoder, and so for capturing the two shadow-notch signals at each micrometre of the test fibre's travel. Calibration, across the four detectors of this work, gave a vibrational responsivity in voltage terms of (9.45 ± 1.20) MV (rms)/m, yielding a VM displacement sensitivity of (69 ± 13) pm (rms)/?Hz, at 500 Hz, over the required measuring span of ±0.1 mm.

Lockerbie, N. A.; Tokmakov, K. V. [SUPA (Scottish Universities Physics Alliance), Department of Physics, University of Strathclyde, 107 Rottenrow, Glasgow G4 0NG (United Kingdom)

2014-10-15T23:59:59.000Z

While these samples are representative of the content of NLE

they are not comprehensive nor are they the most current set.

We encourage you to perform a real-time search of NLE

to obtain the most current and comprehensive results.

61

Optics in a nonlinear gravitational wave

Gravitational waves can act like gravitational lenses, affecting the observed positions, brightnesses, and redshifts of distant objects. Exact expressions for such effects are derived here, allowing for arbitrarily-moving sources and observers in the presence of plane-symmetric gravitational waves. The commonly-used predictions of linear perturbation theory are shown to be generically overshadowed---even for very weak gravitational waves---by nonlinear effects when considering observations of sufficiently distant sources; higher-order perturbative corrections involve secularly-growing terms which cannot necessarily be neglected. Even on more moderate scales where linear effects remain at least marginally dominant, nonlinear corrections are qualitatively different from their linear counterparts. There is a sense in which they can, for example, mimic the existence of a third type of gravitational wave polarization.

Harte, Abraham I

2015-01-01T23:59:59.000Z

62

Strings in plane-fronted gravitational waves

Brinkmann's plane-fronted gravitational waves with parallel rays --~shortly pp-waves~-- are shown to provide, under suitable conditions, exact string vacua at all orders of the sigma-model perturbation expansion.

C. Duval; Z. Horvath; P. A. Horvathy

2006-02-13T23:59:59.000Z

63

Sources of Gravitational Waves: Theory and Observations

Gravitational-wave astronomy will soon become a new tool for observing the Universe. Detecting and interpreting gravitational waves will require deep theoretical insights into astronomical sources. The past three decades have seen remarkable progress in analytical and numerical computations of the source dynamics, development of search algorithms and analysis of data from detectors with unprecedented sensitivity. This Chapter is devoted to examine the advances and future challenges in understanding the dynamics of binary and isolated compact-object systems, expected cosmological sources, their amplitudes and rates, and highlights of results from gravitational-wave observations. All of this is a testament to the readiness of the community to open a new window for observing the cosmos, a century after gravitational waves were first predicted by Albert Einstein.

Alessandra Buonanno; B. S. Sathyaprakash

2014-10-28T23:59:59.000Z

64

Propagation of gravitational waves in multimetric gravity

We discuss the propagation of gravitational waves in a recently discussed class of theories containing N >= 2 metric tensors and a corresponding number of standard model copies. Using the formalism of gauge-invariant linear perturbation theory we show that all gravitational waves propagate at the speed of light. We then employ the Newman-Penrose formalism to show that two to six polarizations of gravitational waves may exist, depending on the parameters entering the equations of motion. This corresponds to E(2) representations N_2, N_3, III_5 and II_6. We finally apply our general discussion to a recently presented concrete multimetric gravity model and show that it is of class N_2, i.e., it allows only two tensor polarizations, as it is the case for general relativity. Our results provide the theoretical background for tests of multimetric gravity theories using the upcoming gravitational wave experiments.

Manuel Hohmann

2012-04-22T23:59:59.000Z

65

Power recycling for an interferometric gravitational wave

THESIS Power recycling for an interferometric gravitational wave detector Masaki Ando Department . . . . . . . . . . . . . . 48 3.3 Power recycling . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 3.3.1 Principle of power recycling . . . . . . . . . . . . . . . . . 50 3.3.2 Recycling cavity

Ejiri, Shinji

66

Numerical wave optics and the lensing of gravitational waves by globular clusters

We consider the possible effects of gravitational lensing by globular clusters on gravitational waves from asymmetric neutron stars in our galaxy. In the lensing of gravitational waves, the long wavelength, compared with the usual case of optical lensing, can lead to the geometrical optics approximation being invalid, in which case a wave optical solution is necessary. In general, wave optical solutions can only be obtained numerically. We describe a computational method that is particularly well suited to numerical wave optics. This method enables us to compare the properties of several lens models for globular clusters without ever calling upon the geometrical optics approximation, though that approximation would sometimes have been valid. Finally, we estimate the probability that lensing by a globular cluster will significantly affect the detection, by ground-based laser interferometer detectors such as LIGO, of gravitational waves from an asymmetric neutron star in our galaxy, finding that the probability is insignificantly small.

Andrew J. Moylan; David E. McClelland; Susan M. Scott; Antony C. Searle; G. V. Bicknell

2007-10-16T23:59:59.000Z

67

We estimated the sensitivity of the upcoming advanced, ground-based gravitational-wave observatories (the upgraded LIGO and Virgo and the KAGRA interferometers) to coalescing intermediate mass black hole binaries (IMBHB). We added waveforms modeling the gravitational radiation emitted by IMBHBs to detectors' simulated data and searched for the injected signals with the coherent WaveBurst algorithm. The tested binary's parameter space covers non-spinning IMBHBs with source-frame total masses between 50 and 1050 $\\text{M}_{\\odot}$ and mass ratios between $1/6$ and 1$\\,$. We found that advanced detectors could be sensitive to these systems up to a range of a few Gpc. A theoretical model was adopted to estimate the expected observation rates, yielding up to a few tens of events per year. Thus, our results indicate that advanced detectors will have a reasonable chance to collect the first direct evidence for intermediate mass black holes and open a new, intriguing channel for probing the Universe over cosmological scales.

G. Mazzolo; F. Salemi; M. Drago; V. Necula; C. Pankow; G. A. Prodi; V. Re; V. Tiwari; G. Vedovato; I. Yakushin; S. Klimenko

2014-05-02T23:59:59.000Z

68

We report the results of a multimessenger search for coincident signals from the LIGO and Virgo gravitational-wave observatories and the partially completed IceCube high-energy neutrino detector, including periods of joint ...

Aartsen, M.?G.

69

Subtraction-noise projection in gravitational-wave detector networks

In this paper, we present a successful implementation of a subtraction-noise projection method into a simple, simulated data analysis pipeline of a gravitational-wave search. We investigate the problem to reveal a weak stochastic background signal which is covered by a strong foreground of compact-binary coalescences. The foreground, which is estimated by matched filters, has to be subtracted from the data. Even an optimal analysis of foreground signals will leave subtraction noise due to estimation errors of template parameters which may corrupt the measurement of the background signal. The subtraction noise can be removed by a noise projection. We apply our analysis pipeline to the proposed future-generation space-borne Big Bang Observer mission which seeks for a stochastic background of primordial gravitational waves in the frequency range {approx}0.1 Hz--1 Hz covered by a foreground of black-hole and neutron-star binaries. Our analysis is based on a simulation code which provides a dynamical model of a time-delay interferometer network. It generates the data as time series and incorporates the analysis pipeline together with the noise projection. Our results confirm previous ad hoc predictions which say that the Big Bang Observer will be sensitive to backgrounds with fractional energy densities below {omega}=10{sup -16}.

Harms, Jan; Mahrdt, Christoph; Otto, Markus; Priess, Malte [Institut fuer Gravitationsphysik, Universitaet Hannover and Max-Planck-Institut fuer Gravitationsphysik (Albert-Einstein-Institut), Callinstrasse 38, 30167 Hannover (Germany)

2008-06-15T23:59:59.000Z

70

Detecting high-frequency gravitational waves with optically-levitated sensors

We propose a tunable resonant sensor to detect gravitational waves in the frequency range of 50-300 kHz using optically trapped and cooled dielectric microspheres or micro-discs. The technique we describe can exceed the sensitivity of laser-based gravitational wave observatories in this frequency range, using an instrument of only a few percent of their size. Such a device extends the search volume for gravitational wave sources above 100 kHz by 1 to 3 orders of magnitude, and could detect monochromatic gravitational radiation from the annihilation of QCD axions in the cloud they form around stellar mass black holes within our galaxy due to the superradiance effect.

Asimina Arvanitaki; Andrew A. Geraci

2013-01-02T23:59:59.000Z

71

E-Print Network 3.0 - advanced gravitational wave Sample Search...

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

gravitational wave Search Powered by Explorit Topic List Advanced Search Sample search results for: advanced gravitational wave Page: << < 1 2 3 4 5 > >> 1 Gravitational waves...

72

Measuring neutron-star ellipticity with measurements of the stochastic gravitational-wave background

Galactic neutron stars are a promising source of gravitational waves in the analysis band of detectors such as LIGO and Virgo. Previous searches for gravitational waves from neutron stars have focused on the detection of individual neutron stars, which are either nearby or highly non-spherical. Here we consider the stochastic gravitational-wave signal arising from the ensemble of Galactic neutron stars. Using a population synthesis model, we estimate the single-sigma sensitivity of current and planned gravitational-wave observatories to average neutron star ellipticity $\\epsilon$ as a function of the number of in-band Galactic neutron stars $N_\\text{tot}$. For the plausible case of $N_\\text{tot}\\approx 53000$, and assuming one year of observation time with colocated initial LIGO detectors, we find it to be $\\sigma_\\epsilon=2.1\\times10^{-7}$, which is comparable to current bounds on some nearby neutron stars. (The current best $95\\%$ upper limits are $\\epsilon\\lesssim7\\times10^{-8}.$) It is unclear if Advanced LIGO can significantly improve on this sensitivity using spatially separated detectors. For the proposed Einstein Telescope, we estimate that $\\sigma\\epsilon=5.6\\times10^{-10}$. Finally, we show that stochastic measurements can be combined with measurements of individual neutron stars in order to estimate the number of in-band Galactic neutron stars. In this way, measurements of stochastic gravitational waves provide a complementary tool for studying Galactic neutron stars.

Dipongkar Talukder; Eric Thrane; Sukanta Bose; Tania Regimbau

2014-06-12T23:59:59.000Z

73

A derivation of the optical axis lenght fluctations due by tilts of the mirrors of the Fabry-Perot cavity of long-baseline interferometers for the detection of gravitational waves in presence of the gravitational field of the earth is discussed. By comparing with the typical tilt-induced noises it is shown that this potential signal, which is considered a weak source of noise, is negligible for the first generation of gravitational waves interferometers, but, in principle, this effect could be used for high precision measures of the gravitational acceleration if advanced projects will achieve an high sensitivity. In that case the precision of the misure could be higher than the gravimeter realized by the Istituto di Metrologia ``Gustavo Colonnetti''.

Christian Corda

2007-01-25T23:59:59.000Z

74

The gravitational wave symphony of the Universe

The new millennium will see the upcoming of several ground-based interferometric gravitational wave antennas. Within the next decade a space-based antenna may also begin to observe the distant Universe. These gravitational wave detectors will together operate as a network taking data continuously for several years, watching the transient and continuous phenomena occurring in the deep cores of astronomical objects and dense environs of the early Universe where gravity was extremely strong and highly non-linear. The network will listen to the waves from rapidly spinning non-axisymmetric neutron stars, normal modes of black holes, binary black hole inspiral and merger, phase transitions in the early Universe, quantum fluctuations resulting in a characteristic background in the early Universe. The gravitational wave antennas will open a new window to observe the dark Universe unreachable via other channels of astronomical observations.

B. S. Sathyaprakash

2002-07-10T23:59:59.000Z

75

Gravitational waves and gamma-ray bursts

Gamma-Ray Bursts are likely associated with a catastrophic energy release in stellar mass objects. Electromagnetic observations provide important, but indirect information on the progenitor. On the other hand, gravitational waves emitted from the central source, carry direct information on its nature. In this context, I give an overview of the multi-messenger study of gamma-ray bursts that can be carried out by using electromagnetic and gravitational wave observations. I also underline the importance of joint electromagnetic and gravitational wave searches, in the absence of a gamma-ray trigger. Finally, I discuss how multi-messenger observations may probe alternative gamma-ray burst progenitor models, such as the magnetar scenario.

Alessandra Corsi; for the LIGO Scientific Collaboration; for the Virgo Collaboration

2012-05-11T23:59:59.000Z

76

Discovering the QCD Axion with Black Holes and Gravitational Waves

Advanced LIGO will be the first experiment to detect gravitational waves. Through superradiance of stellar black holes, it may also be the first experiment to discover the QCD axion with decay constant above the GUT scale. When an axion's Compton wavelength is comparable to the size of a black hole, the axion binds to the black hole, forming a "gravitational atom." Through the superradiance process, the number of axions occupying the bound levels grows exponentially, extracting energy and angular momentum from the black hole. Axions transitioning between levels of the gravitational atom and axions annihilating to gravitons produce observable gravitational wave signals. The signals are long-lasting, monochromatic, and can be distinguished from ordinary astrophysical sources. We estimate up to O(1) transition events at aLIGO for an axion between 10^-11 and 10^-10 eV and up to 10^4 annihilation events for an axion between 10^-13 and 10^-11 eV. In the event of a null search, aLIGO can constrain the axion mass as a function of the formation rate of rapidly spinning black holes. Axion annihilations are also promising for much lighter masses at future lower-frequency gravitational wave observatories, where we expect as many as $10^5$ events. Our projections for aLIGO are robust against perturbations from the black hole environment and account for our updated exclusion on the QCD axion of 6 * 10^-13 eV < ma < 2 * 10^-11 eV suggested by stellar black hole spin measurements.

Asimina Arvanitaki; Masha Baryakhtar; Xinlu Huang

2014-12-15T23:59:59.000Z

77

Gravitational wave background from Standard Model physics: Qualitative features

Because of physical processes ranging from microscopic particle collisions to macroscopic hydrodynamic fluctuations, any plasma in thermal equilibrium emits gravitational waves. For the largest wavelengths the emission rate is proportional to the shear viscosity of the plasma. In the Standard Model at T > 160 GeV, the shear viscosity is dominated by the most weakly interacting particles, right-handed leptons, and is relatively large. We estimate the order of magnitude of the corresponding spectrum of gravitational waves. Even though at small frequencies (corresponding to the sub-Hz range relevant for planned observatories such as eLISA) this background is tiny compared with that from non-equilibrium sources, the total energy carried by the high-frequency part of the spectrum is non-negligible if the production continues for a long time. We suggest that this may constrain (weakly) the highest temperature of the radiation epoch. Observing the high-frequency part directly sets a very ambitious goal for future ge...

Ghiglieri, J

2015-01-01T23:59:59.000Z

78

Gravitational-wave sensitivity curves

Virgo) respectively. The upgraded, second-generation versions are referred to as Advanced LIGO (aLIGO) and Advanced Virgo (AdV) respectively. LIGO has two observatories: one at Hanford, Washington, which has two detectors; and another at Livingston, Louisiana... . There is an agreement to move one of the upgraded Hanford detector systems to a location in India (Iyer et al., 2011; Unnikrishnan, 2013). The GEO600 detector is not subject to a major upgrade plan, but since summer 2009 it has been enhanced by a series of smaller...

Moore, C. J.; Cole, R. H.; Berry, C. P. L.

2014-12-08T23:59:59.000Z

79

Interaction of Gravitational Waves with Charged Particles

It is shown here that a cloud of charged particles could in principle absorb energy from gravitational waves (GWs) incident upon it, resulting in wave attenuation. This could in turn have implications for the interpretation of future data from early universe GWs.

Thulsi Wickramasinghe; Will Rhodes; Mitchell Revalski

2015-02-03T23:59:59.000Z

80

On the Energy of Rotating Gravitational Waves

A class of solutions of the gravitational field equations describing vacuum spacetimes outside rotating cylindrical sources is presented. A subclass of these solutions corresponds to the exterior gravitational fields of rotating cylindrical systems that emit gravitational radiation. The properties of these rotating gravitational wave spacetimes are investigated. In particular, we discuss the energy density of these waves using the gravitational stress-energy tensor.

Bahram Mashhoon; James C. McClune; Enrique Chavez; Hernando Quevedo

1996-09-06T23:59:59.000Z

While these samples are representative of the content of NLE

they are not comprehensive nor are they the most current set.

We encourage you to perform a real-time search of NLE

to obtain the most current and comprehensive results.

81

Interaction of Gravitational Waves with Charged Particles

It is shown here that a cloud of charged particles could in principle absorb energy from gravitational waves (GWs) incident upon it, resulting in wave attenuation. This could in turn have implications for the interpretation of future data from early universe GWs.

Wickramasinghe, Thulsi; Revalski, Mitchell

2015-01-01T23:59:59.000Z

82

On the Vacuum Propagation of Gravitational Waves

We show that, for any local, causal quantum field theory which couples covariantly to gravity, and which admits Minkowski spacetime vacuum(a) invariant under the inhomogeneous proper orthochronous Lorentz group, plane gravitational waves propagating in such Minkowski vacuum(a) do not dissipate energy or momentum via quantum field theoretic effects.

Xiao Liu

2007-06-05T23:59:59.000Z

83

Initial data for Einstein's equations with superposed gravitational waves

A method is presented to construct initial data for Einstein's equations as a superposition of a gravitational wave perturbation on an arbitrary stationary background spacetime. The method combines the conformal thin sandwich formalism with linear gravitational waves, and allows detailed control over characteristics of the superposed gravitational wave like shape, location and propagation direction. It is furthermore fully covariant with respect to spatial coordinate changes and allows for very large amplitude of the gravitational wave.

Harald P. Pfeiffer; Lawrence E. Kidder; Mark A. Scheel; Deirdre Shoemaker

2005-02-22T23:59:59.000Z

84

Acceleration of low energy charged particles by gravitational waves

The acceleration of charged particles in the presence of a magnetic field and gravitational waves is under consideration. It is shown that the weak gravitational waves can cause the acceleration of low energy particles under appropriate conditions. Such conditions may be satisfied close to the source of the gravitational waves if the magnetized plasma is in a turbulent state.

G. Voyatzis; L. Vlahos; S. Ichtiaroglou; D. Papadopoulos

2005-12-07T23:59:59.000Z

85

Gravitational Waves in Ghost Free Bimetric Gravity

We obtain a set of exact gravitational wave solutions for the ghost free bimetric theory of gravity. With a flat reference metric, the theory admits the vacuum Brinkmann plane wave solution for suitable choices of the coefficients of different terms in the interaction potential. An exact gravitational wave solution corresponding to a massive scalar mode is also admitted for arbitrary choice of the coefficients with the reference metric being proportional to the spacetime metric. The proportionality factor and the speed of the wave are calculated in terms of the parameters of the theory. We also show that a F(R) extension of the theory admits similar solutions but in general is plagued with ghost instabilities.

Morteza Mohseni

2012-11-15T23:59:59.000Z

86

Gravitational coupling of the propagation four-vectors of matter wave functions is formulated in flat space-time. Coupling at the momentum level rather than at the "force-law" level greatly simplifies many calculations. This locally Lorentz-invariant approach (G4v) treats electromagnetic and gravitational coupling on an equal footing. Classical mechanics emerges from the incoherent aggregation of matter wave functions. The theory reproduces, to first order beyond Newton, the standard GR results for Gravity-Probe B, deflection of light by massive bodies, precession of orbits, gravitational red shift, and total gravitational-wave energy radiated by a circular binary system. Its predictions of total radiated energy from highly eccentric Kepler systems are slightly larger than those of similar GR treatments. G4v predictions differ markedly from those of GR for the gravitational-wave radiation patterns from rotating massive systems, and for the LIGO antenna pattern. The predicted antenna patterns have been shown t...

Mead, Carver

2015-01-01T23:59:59.000Z

87

Energy-momentum Density of Gravitational Waves

In this paper, we elaborate the problem of energy-momentum in general relativity by energy-momentum prescriptions theory. Our aim is to calculate energy and momentum densities for the general form of gravitational waves. In this connection, we have extended the previous works by using the prescriptions of Bergmann and Tolman. It is shown that they are finite and reasonable. In addition, using Tolman prescription, exactly, leads to same results that have been obtained by Einstein and Papapetrou prescriptions.

Amir M. Abbassi; Saeed Mirshekari

2014-11-29T23:59:59.000Z

88

Possible Enhancement of High Frequency Gravitational Waves

We study the tensor perturbations in a class of non-local, purely gravitational models which naturally end inflation in a distinctive phase of oscillations with slight and short violations of the weak energy condition. We find the usual generic form for the tensor power spectrum. The presence of the oscillatory phase leads to an enhancement of gravitational waves with frequencies somewhat less than 10^{10} Hz.

Maria G. Romania; N. C. Tsamis; R. P. Woodard

2011-03-05T23:59:59.000Z

89

Non-expanding impulsive gravitational waves

We investigate a class of impulsive gravitational waves which propagate either in Minkowski or in the (anti-)de Sitter background. These waves are constructed as impulsive members of the Kundt class $P(\\Lambda)$ of non-twisting, non-expanding type N solutions of vacuum Einstein equations with a cosmological constant $\\Lambda$. We show that the only non-trivial waves of this type in Minkowski spacetime are impulsive pp-waves. For $\\Lambda\

J. Podolsky

1998-07-29T23:59:59.000Z

90

Do Mirrors for Gravitational Waves Exist?

Thin superconducting films are predicted to be highly reflective mirrors for gravitational waves at microwave frequencies. The quantum mechanical non-localizability of the negatively charged Cooper pairs, which is protected from the localizing effect of decoherence by an energy gap, causes the pairs to undergo non-picturable, non-geodesic motion in the presence of a gravitational wave. This non-geodesic motion, which is accelerated motion through space, leads to the existence of mass and charge supercurrents inside the superconducting film. On the other hand, the decoherence-induced localizability of the positively charged ions in the lattice causes them to undergo picturable, geodesic motion as they are carried along with space in the presence of the same gravitational wave. The resulting separation of charges leads to a virtual plasma excitation within the film that enormously enhances its interaction with the wave, relative to that of a neutral superfluid or any normal matter. The existence of strong mass supercurrents within a superconducting film in the presence of a gravitational wave, dubbed the "Heisenberg-Coulomb effect," implies the specular reflection of a gravitational microwave from a film whose thickness is much less than the London penetration depth of the material, in close analogy with the electromagnetic case. The argument is developed by allowing classical gravitational fields, which obey Maxwell-like equations, to interact with quantum matter, which is described using the BCS and Ginzburg-Landau theories of superconductivity, as well as a collisionless plasma model. Several possible experimental tests of these ideas, including mesoscopic ones, are presented alongside comments on the broader theoretical implications of the central hypothesis.

Stephen J. Minter; Kirk Wegter-McNelly; Raymond Y. Chiao

2009-06-30T23:59:59.000Z

91

Gravitational coupling of the propagation four-vectors of matter wave functions is formulated in flat space-time. Coupling at the momentum level rather than at the "force-law" level greatly simplifies many calculations. This locally Lorentz-invariant approach (G4v) treats electromagnetic and gravitational coupling on an equal footing. Classical mechanics emerges from the incoherent aggregation of matter wave functions. The theory reproduces, to first order beyond Newton, the standard GR results for Gravity-Probe B, deflection of light by massive bodies, precession of orbits, gravitational red shift, and total gravitational-wave energy radiated by a circular binary system. Its predictions of total radiated energy from highly eccentric Kepler systems are slightly larger than those of similar GR treatments. G4v predictions differ markedly from those of GR for the gravitational-wave radiation patterns from rotating massive systems, and for the LIGO antenna pattern. The predicted antenna patterns have been shown to be highly distinguishable in the case of continuous gravitational-wave sources, and should therefore be testable as data from Advanced LIGO becomes available over the next few years.

Carver Mead

2015-03-16T23:59:59.000Z

92

Template banks to search for low-mass binary black holes in advanced gravitational-wave detectors

Coalescing binary black holes (BBHs) are among the most likely sources for the Laser Interferometer Gravitational-wave Observatory (LIGO) and its international partners Virgo and KAGRA. Optimal searches for BBHs require accurate waveforms for the signal model and effectual template banks that cover the mass space of interest. We investigate the ability of the second-order post-Newtonian TaylorF2 hexagonal template placement metric to construct an effectual template bank, if the template waveforms used are effective one body waveforms tuned to numerical relativity (EOBNRv2). We find that by combining the existing TaylorF2 placement metric with EOBNRv2 waveforms, we can construct an effectual search for BBHs with component masses in the range 3 Msolar searches. We find that for systems with (m_1/m_2)= 2.68 radians, there is no significant loss in the total possible signal-to-noise ratio due to neglecting modes other than l = m = 2 in the template waveforms. For a source population uniformly distributed in spacial volume, over the entire sampled region of the component-mass space, the loss in detection rate (averaged over a uniform distribution of inclination angle and sky-location/polarization angles), remains below ~11%. For binaries with high mass-ratios \\textit{and} 0.31 Advanced LIGO. Our results can be used to construct matched-filter searches in Advanced LIGO and Advanced Virgo.

Duncan A. Brown; Prayush Kumar; Alexander H. Nitz

2013-03-15T23:59:59.000Z

93

Gravitational waves from known pulsars: results from the initial detector era

We present the results of searches for gravitational waves from a large selection of pulsars using data from the most recent science runs (S6, VSR2 and VSR4) of the initial generation of interferometric gravitational wave detectors LIGO (Laser Interferometric Gravitational-wave Observatory) and Virgo. We do not see evidence for gravitational wave emission from any of the targeted sources but produce upper limits on the emission amplitude. We highlight the results from seven young pulsars with large spin-down luminosities. We reach within a factor of five of the canonical spin-down limit for all seven of these, whilst for the Crab and Vela pulsars we further surpass their spin-down limits. We present new or updated limits for 172 other pulsars (including both young and millisecond pulsars). Now that the detectors are undergoing major upgrades, and, for completeness, we bring together all of the most up-to-date results from all pulsars searched for during the operations of the first-generation LIGO, Virgo and GEO600 detectors. This gives a total of 195 pulsars including the most recent results described in this paper.

J. Aasi; J. Abadie; B. P. Abbott; R. Abbott; T. Abbott; M. R. Abernathy; T. Accadia; F. Acernese; C. Adams; T. Adams; R. X. Adhikari; C. Affeldt; M. Agathos; N. Aggarwal; O. D. Aguiar; P. Ajith; B. Allen; A. Allocca; E. Amador Ceron; D. Amariutei; R. A. Anderson; S. B. Anderson; W. G. Anderson; K. Arai; M. C. Araya; C. Arceneaux; J. Areeda; S. Ast; S. M. Aston; P. Astone; P. Aufmuth; C. Aulbert; L. Austin; B. E. Aylott; S. Babak; P. T. Baker; G. Ballardin; S. W. Ballmer; J. C. Barayoga; D. Barker; S. H. Barnum; F. Barone; B. Barr; L. Barsotti; M. Barsuglia; M. A. Barton; I. Bartos; R. Bassiri; A. Basti; J. Batch; J. Bauchrowitz; Th. S. Bauer; M. Bebronne; B. Behnke; M. Bejger; M. G. Beker; A. S. Bell; C. Bell; I. Belopolski; G. Bergmann; J. M. Berliner; D. Bersanetti; A. Bertolini; D. Bessis; J. Betzwieser; P. T. Beyersdorf; T. Bhadbhade; I. A. Bilenko; G. Billingsley; J. Birch; M. Bitossi; M. A. Bizouard; E. Black; J. K. Blackburn; L. Blackburn; D. Blair; M. Blom; O. Bock; T. P. Bodiya; M. Boer; C. Bogan; C. Bond; F. Bondu; L. Bonelli; R. Bonnand; R. Bork; M. Born; V. Boschi; S. Bose; L. Bosi; J. Bowers; C. Bradaschia; P. R. Brady; V. B. Braginsky; M. Branchesi; C. A. Brannen; J. E. Brau; J. Breyer; T. Briant; D. O. Bridges; A. Brillet; M. Brinkmann; V. Brisson; M. Britzger; A. F. Brooks; D. A. Brown; D. D. Brown; F. Brückner; T. Bulik; H. J. Bulten; A. Buonanno; D. Buskulic; C. Buy; R. L. Byer; L. Cadonati; G. Cagnoli; J. Calderón Bustillo; E. Calloni; J. B. Camp; P. Campsie; K. C. Cannon; B. Canuel; J. Cao; C. D. Capano; F. Carbognani; L. Carbone; S. Caride; A. Castiglia; S. Caudill; M. Cavagliŕ; F. Cavalier; R. Cavalieri; G. Cella; C. Cepeda; E. Cesarini; R. Chakraborty; T. Chalermsongsak; S. Chao; P. Charlton; E. Chassande-Mottin; X. Chen; Y. Chen; A. Chincarini; A. Chiummo; H. S. Cho; J. Chow; N. Christensen; Q. Chu; S. S. Y. Chua; S. Chung; G. Ciani; F. Clara; D. E. Clark; J. A. Clark; F. Cleva; E. Coccia; P. -F. Cohadon; A. Colla; M. Colombini; M. Constancio Jr.; A. Conte; R. Conte; D. Cook; T. R. Corbitt; M. Cordier; N. Cornish; A. Corsi; C. A. Costa; M. W. Coughlin; J. -P. Coulon; S. Countryman; P. Couvares; D. M. Coward; M. Cowart; D. C. Coyne; K. Craig; J. D. E. Creighton; T. D. Creighton; S. G. Crowder; A. Cumming; L. Cunningham; E. Cuoco; K. Dahl; T. Dal Canton; M. Damjanic; S. L. Danilishin; S. D'Antonio; K. Danzmann; V. Dattilo; B. Daudert; H. Daveloza; M. Davier; G. S. Davies; E. J. Daw; R. Day; T. Dayanga; R. De Rosa; G. Debreczeni; J. Degallaix; W. Del Pozzo; E. Deleeuw; S. Deléglise; T. Denker; T. Dent; H. Dereli; V. Dergachev; R. DeRosa; R. DeSalvo; S. Dhurandhar; L. Di Fiore; A. Di Lieto; I. Di Palma; A. Di Virgilio; M. Díaz; A. Dietz; K. Dmitry; F. Donovan; K. L. Dooley; S. Doravari; M. Drago; R. W. P. Drever; J. C. Driggers; Z. Du; J. -C. Dumas; S. Dwyer; T. Eberle; M. Edwards; A. Effler; P. Ehrens; J. Eichholz; S. S. Eikenberry; G. Endr?czi; R. Essick; T. Etzel; K. Evans; M. Evans; T. Evans; M. Factourovich; V. Fafone; S. Fairhurst; Q. Fang; S. Farinon; B. Farr; W. Farr; M. Favata; D. Fazi; H. Fehrmann; D. Feldbaum; I. Ferrante; F. Ferrini; F. Fidecaro; L. S. Finn; I. Fiori; R. Fisher; R. Flaminio; E. Foley; S. Foley; E. Forsi; N. Fotopoulos; J. -D. Fournier; S. Franco; S. Frasca; F. Frasconi; M. Frede; M. Frei; Z. Frei; A. Freise; R. Frey; T. T. Fricke; P. Fritschel; V. V. Frolov; M. -K. Fujimoto; P. Fulda; M. Fyffe; J. Gair; L. Gammaitoni; J. Garcia; F. Garufi; N. Gehrels; G. Gemme; E. Genin; A. Gennai; L. Gergely; S. Ghosh; J. A. Giaime; S. Giampanis; K. D. Giardina; A. Giazotto; S. Gil-Casanova; C. Gill; J. Gleason; E. Goetz; R. Goetz; L. Gondan; G. González; N. Gordon; M. L. Gorodetsky; S. Gossan; S. Goßler; R. Gouaty; C. Graef; P. B. Graff; M. Granata; A. Grant; S. Gras; C. Gray; R. J. S. Greenhalgh; A. M. Gretarsson; C. Griffo; P. Groot; H. Grote; K. Grover; S. Grunewald; G. M. Guidi; C. Guido; K. E. Gushwa; E. K. Gustafson; R. Gustafson; B. Hall; E. Hall; D. Hammer; G. Hammond; M. Hanke; J. Hanks; C. Hanna; J. Hanson; J. Harms; G. M. Harry; I. W. Harry; E. D. Harstad; M. T. Hartman; K. Haughian; K. Hayama; J. Heefner; A. Heidmann; M. Heintze; H. Heitmann; P. Hello; G. Hemming; M. Hendry; I. S. Heng; A. W. Heptonstall; M. Heurs; S. Hild; D. Hoak; K. A. Hodge; K. Holt; M. Holtrop; T. Hong; S. Hooper; T. Horrom; D. J. Hosken; J. Hough; E. J. Howell; Y. Hu; Z. Hua; V. Huang; E. A. Huerta; B. Hughey; S. Husa; S. H. Huttner; M. Huynh; T. Huynh-Dinh; J. Iafrate; D. R. Ingram; R. Inta; T. Isogai; A. Ivanov; B. R. Iyer; K. Izumi; M. Jacobson; E. James; H. Jang; Y. J. Jang; P. Jaranowski; F. Jiménez-Forteza; W. W. Johnson; D. Jones; D. I. Jones; R. Jones; R. J. G. Jonker; L. Ju; Haris K; P. Kalmus; V. Kalogera; S. Kandhasamy; G. Kang; J. B. Kanner; M. Kasprzack; R. Kasturi; E. Katsavounidis; W. Katzman; H. Kaufer; K. Kaufman; K. Kawabe; S. Kawamura; F. Kawazoe

2014-04-24T23:59:59.000Z

94

Detecting Planets around Compact Binaries with Gravitational Wave Detectors in Space

I propose a method to detect planets around compact binaries that are strong sources of gravitational radiation. This approach is to measure gravitational-wave phase modulations induced by the planets, and its prospect is studied with a Fisher matrix analysis. I find that, using the Laser Interferometer Space Antenna (LISA), planets can be searched for around ~3000 Galactic double white dwarfs with detection limit ~4 M_J (M_J~ 2x10^{30}g: the Jupiter mass). With its follow-on missions, planets with mass ~1 M_J might be detected around double neutron stars even at cosmological distances z~1. In this manner, gravitational wave observation has potential to make interesting contributions to extra-solar planetary science.

Naoki Seto

2008-02-22T23:59:59.000Z

95

The role that the quantum properties of a gravitational wave could play in the detection of gravitational radiation is analyzed. It is not only corroborated that in the current laser-interferometric detectors the resolution of the experimental apparatus could lie very far from the corresponding quantum threshold (thus the backreaction effect of the measuring device upon the gravitational wave is negligible), but it is also suggested that the consideration of the quantum properties of the wave could entail the definition of dispersion of the measurement outputs. This dispersion would be a function not only of the sensitivity of the measuring device, but also of the interaction time (between measuring device and gravitational radiation) and of the arm length of the corresponding laser- interferometer. It would have a minimum limit, and the introduction of the current experimental parameters insinuates that the dispersion of the existing proposals could lie very far from this minimum, which means that they would show a very large dispersion.

A. Camacho

1998-07-10T23:59:59.000Z

96

Seismic gravity-gradient noise in interferometric gravitational-wave detectors

When ambient seismic waves pass near an interferometric gravitational-wave detector, they induce density perturbations in the earth which produce fluctuating gravitational forces on the interferometer's test masses. These forces mimic a stochastic background of gravitational waves and thus constitute noise. We compute this noise using the theory of multimode Rayleigh and Love waves propagating in a layered medium that approximates the geological strata at the LIGO sites. We characterize the noise by a transfer function $T(f) \\equiv \\tilde x(f)/\\tilde W(f)$ from the spectrum of direction averaged ground motion $\\tilde W(f)$ to the spectrum of test mass motion $\\tilde x(f) = L\\tilde h(f)$ (where $L$ is the length of the interferometer's arms, and $\\tilde h(f)$ is the spectrum of gravitational-wave noise). This paper's primary foci are (i) a study of how $T(f)$ depends on the various seismic modes; (ii) an attempt to estimate which modes are excited at the LIGO sites at quiet and noisy times; and (iii) a corresponding estimate of the seismic gravity-gradient noise level. At quiet times the noise is below the benchmark noise level of ``advanced LIGO interferometers'' (although not by much near 10 Hz); it may significantly exceed this level at noisy times. The lower edge of our quiet-time noise is a limit beyond which there is little gain from further improvements in vibration isolation and thermal noise, unless one also reduces seismic gravity-gradient noise. Two methods of reduction are discussed: monitoring the earth's density perturbations, computing their gravitational forces, and correcting the data for those forces; and constructing narrow moats around the interferometers' test masses to shield out the fundamental-mode Rayleigh waves, which we suspect dominate at quiet times.

Scott A. Hughes; Kip S. Thorne

1998-06-03T23:59:59.000Z

97

We compute the emission of gravitational radiation from pulsating white dwarfs. This is done by using an up-to-date stellar evolutionary code coupled with a state-of-the-art pulsational code. The emission of gravitational waves is computed for a standard 0.6 solar masses white dwarf with a liquid carbon-oxygen core and a hydrogen-rich envelope, for a massive DA white dwarf with a partially crystallized core for which various l=2 modes have been observed (BPM 37093) and for PG 1159-035, the prototype of the GW Vir class of variable stars, for which several quadrupole modes have been observed as well. We find that these stars do not radiate sizeable amounts of gravitational waves through their observed pulsation g-modes, in line with previous studies. We also explore the possibility of detecting gravitational waves radiated by the f-mode and the p-modes. We find that in this case the gravitational wave signal is very large and, hence, the modes decay very rapidly. We also discuss the possible implications of our calculations for the detection of gravitational waves from pulsating white dwarfs within the framework of future space-borne interferometers like LISA.

E. Garcia-Berro; P. Loren-Aguilar; A. H. Corsico; L. G. Althaus; J. A. Lobo; J. Isern

2005-09-13T23:59:59.000Z

98

Gravitational waves from a curvaton model with blue spectrum

We investigate the gravitational wave background induced by the first order scalar perturbations in the curvaton models. We consider the quadratic and axion-like curvaton potential which can generate the blue-tilted power spectrum of curvature perturbations on small scales and derive the maximal amount of gravitational wave background today. We find the power spectrum of the induced gravitational wave background has a characteristic peak at the frequency corresponding to the scale reentering the horizon at the curvaton decay, in the case where the curvaton does not dominate the energy density of the Universe. We also find the enhancement of the amount of the gravitational waves in the case where the curvaton dominates the energy density of the Universe. Such induced gravitational waves would be detectable by the future space-based gravitational wave detectors or pulsar timing observations.

Kawasaki, Masahiro; Kitajima, Naoya; Yokoyama, Shuichiro, E-mail: kawasaki@icrr.u-tokyo.ac.jp, E-mail: nk610@icrr.u-tokyo.ac.jp, E-mail: shu@icrr.u-tokyo.ac.jp [Institute for Cosmic Ray Research, University of Tokyo, Kashiwa, Chiba 277-8582 (Japan)

2013-08-01T23:59:59.000Z

99

Standing gravitational waves from domain walls

We construct a plane symmetric, standing gravitational wave for a domain wall plus a massless scalar field. The scalar field can be associated with a fluid which has the properties of 'stiff' matter, i.e., matter in which the speed of sound equals the speed of light. Although domain walls are observationally ruled out in the present era, the solution has interesting features which might shed light on the character of exact nonlinear wave solutions to Einstein's equations. Additionally this solution may act as a template for higher dimensional 'brane-world' model standing waves.

Gogberashvili, Merab [Andronikashvili Institute of Physics, 6 Tamarashvili Street, Tbilisi 0177 (Georgia); Javakhishvili Tbilisi State University, 3 Chavchavadze Avenue, Tbilisi 0128 (Georgia); California State University, Fresno, Physics Department, Fresno, California 93740-8031 (United States); Myrzakul, Shynaray [Department of General and Theoretical Physics, Gumilev Eurasian National University, Astana, 010008 (Kazakhstan); California State University, Fresno, Physics Department, Fresno, California 93740-8031 (United States); Singleton, Douglas [California State University, Fresno, Physics Department, Fresno, California 93740-8031 (United States); Institute of Gravitation and Cosmology, Peoples' Friendship University of Russia, Moscow 117198 (Russian Federation)

2009-07-15T23:59:59.000Z

100

Stars as resonant absorbers of gravitational waves

Quadrupole oscillation modes in stars can resonate with incident gravitational waves (GWs), and grow non-linear at the expense of GW energy. Stars near massive black hole binaries (MBHB) can act as GW-charged batteries, cooling radiatively. Mass-loss from these stars can prompt MBHB accretion at near-Eddington rates. GW opacity is independent of amplitude, so distant resonating stars can eclipse GW sources. Absorption by the Sun of GWs from Galactic white dwarf binaries may be detectable with second-generation space-based GW detectors as a shadow within a complex diffraction pattern.

B. McKernan; K. E. S. Ford; B. Kocsis; Z. Haiman

2014-08-28T23:59:59.000Z

While these samples are representative of the content of NLE

they are not comprehensive nor are they the most current set.

We encourage you to perform a real-time search of NLE

to obtain the most current and comprehensive results.

101

Connecting Numerical Relativity and Data Analysis of Gravitational Wave Detectors

Gravitational waves deliver information in exquisite detail about astrophysical phenomena, among them the collision of two black holes, a system completely invisible to the eyes of electromagnetic telescopes. Models that predict gravitational wave signals from likely sources are crucial for the success of this endeavor. Modeling binary black hole sources of gravitational radiation requires solving the Eintein equations of General Relativity using powerful computer hardware and sophisticated numerical algorithms. This proceeding presents where we are in understanding ground-based gravitational waves resulting from the merger of black holes and the implications of these sources for the advent of gravitational-wave astronomy.

Shoemaker, Deirdre; London, Lionel; Pekowsky, Larne

2015-01-01T23:59:59.000Z

102

Gravitational waves from BBH-systems? A (doubly) vain quest

The theoretical reasons at the root of LIGO's experimental failure in searching gravitational waves (GW's) from binary black hole (BBH) inspirals.

A. Loinger

2006-02-06T23:59:59.000Z

103

Mapping the nano-Hertz gravitational wave sky

We describe a new method for extracting gravitational wave signals from pulsar timing data. We show that any gravitational wave signal can be decomposed into an orthogonal set of sky maps, with the number of maps equal to the number of pulsars in the timing array. These maps may be used as a basis to construct gravitational wave templates for any type of source, including collections of point sources. A variant of the standard Hellings-Downs correlation analysis is recovered for statistically isotropic signals. The template based approach allows us to probe potential anisotropies in the signal and produce maps of the gravitational wave sky.

Neil J. Cornish; Rutger van Haasteren

2014-06-19T23:59:59.000Z

104

Radiative Thermal Noise for Transmissive Optics in Gravitational-Wave Detectors

Radiative losses have traditionally been neglected in the calculation of thermal noise of transmissive optical elements because for the most commonly used geometries they are small compared to losses due to thermal conduction. We explore the use of such transmissive optical elements in extremely noise-sensitive environments such as the arm cavities of future gravitational-wave interferometers. This drives us to a geometry regime where radiative losses are no longer negligible. In this paper we derive the thermo-refractive noise associated with such radiative losses and compare it to other known sources of thermal noise.

Sheila Dwyer; Stefan W. Ballmer

2014-08-07T23:59:59.000Z

105

Rank deficiency and Tikhonov regularization in the inverse problem for gravitational-wave bursts

Coherent techniques for searches of gravitational-wave bursts effectively combine data from several detectors, taking into account differences in their responses. The efforts are now focused on the maximum likelihood principle as the most natural way to combine data, which can also be used without prior knowledge of the signal. Recent studies however have shown that straightforward application of the maximum likelihood method to gravitational waves with unknown waveforms can lead to inconsistencies and unphysical results such as discontinuity in the residual functional, or divergence of the variance of the estimated waveforms for some locations in the sky. So far the solutions to these problems have been based on rather different physical arguments. Following these investigations, we now find that all these inconsistencies stem from rank deficiency of the underlying network response matrix. In this paper we show that the detection of gravitational-wave bursts with a network of interferometers belongs to the category of ill-posed problems. We then apply the method of Tikhonov regularization to resolve the rank deficiency and introduce a minimal regulator which yields a well-conditioned solution to the inverse problem for all locations on the sky.

Malik Rakhmanov

2006-09-19T23:59:59.000Z

106

One of the brightest Gamma Ray Burst ever recorded, GRB030329, occurred during the second science run of the LIGO detectors. At that time, both interferometers at the Hanford, WA LIGO site were in lock and acquiring data. The data collected from the two Hanford detectors was analyzed for the presence of a gravitational wave signal associated with this GRB. This paper presents a detailed description of the search algorithm implemented in the current analysis.

S. Mohanty; Sz. Marka; R. Rahkola; S. Mukherjee; I. Leonor; R. Frey; J. Cannizzo; J. Camp

2004-07-15T23:59:59.000Z

107

One of the brightest Gamma Ray Burst ever recorded, GRB030329, occurred during the second science run of the LIGO detectors. At that time, both interferometers at the Hanford, WA LIGO site were in lock and acquiring data. The data collected from the two Hanford detectors was analyzed for the presence of a gravitational wave signal associated with this GRB. This paper presents a detailed description of the search algorithm implemented in the current analysis.

Mohanty, S; Rahkola, R; Mukherjee, S; Leonor, I; Frey, R; Cannizzo, J; Camp, J

2004-01-01T23:59:59.000Z

108

Energy and Momentum of a Class of Rotating Gravitational Waves

We calculate energy and momentum for a class of cylindrical rotating gravitational waves using Einstein and Papapetrou's prescriptions. It is shown that the results obtained are reduced to the special case of the cylindrical gravitational waves already available in the literature.

M. Sharif

2001-02-09T23:59:59.000Z

109

Relic gravitational waves and the generalized second law

The generalized second law of gravitational thermodynamics is applied to the present era of accelerated expansion of the Universe. In spite of the fact that the entropy of matter and relic gravitational waves inside the event horizon diminish, the mentioned law is fulfilled provided that the expression for the entropy density of the gravitational waves satisfies a certain condition.

German Izquierdo; Diego Pavon

2005-01-12T23:59:59.000Z

110

Quantum noise in optical interferometers

We study the photon counting noise in optical interferometers used for gravitational wave detection. In order to reduce quantum noise, a squeezed vacuum is injected into the usually unused input port. It is investigated under which conditions the gravitational wave signal may be amplified without increasing counting noise concurrently. Such a possibility was suggested as a consequence of the entanglement of the two output ports of a beam splitter. We find that amplification without concurrent increase of noise is not possible for reasonable squeezing parameters. Photon distributions for various beam splitter angles and squeezing parameters are calculated.

Voronov, Volodymyr G.; Weyrauch, Michael [Faculty of Physics, Taras Shevchenko National University of Kyiv, 03022 Kyiv (Ukraine); Physikalisch-Technische Bundesanstalt, D-38116 Braunschweig (Germany)

2010-05-15T23:59:59.000Z

111

Stochastic Gravitational Wave Background from Exoplanets

Recent exoplanet surveys have predicted a very large population of planetary systems in our galaxy, more than one planet per star on the average, perhaps totalling about two hundred billion. These surveys, based on electro-magnetic observations, are limited to a very small neighbourhood of the solar system and the estimations rely on the observations of only a few thousand planets. On the other hand, orbital motions of planets around stars are expected to emit gravitational waves (GW), which could provide information about the planets not accessible to electro-magnetic astronomy. The cumulative effect of the planets, with periods ranging from few hours to several years, is expected to create a stochastic GW background (SGWB). We compute the characteristic GW strain of this background based on the observed distribution of planet parameters. We also show that the integrated extragalactic background is comparable or less than the galactic background at different frequencies. Our estimate shows that the net backg...

Ain, Anirban; Mitra, Sanjit

2015-01-01T23:59:59.000Z

112

Gravitational Wave Sources from New Physics

Forthcoming advances in direct gravitational wave detection from kilohertz to nanohertz frequencies have unique capabilities to detect signatures from or set meaningful constraints on a wide range of new cosmological phenomena and new fundamental physics. A brief survey is presented of the post-inflationary gravitational radiation backgrounds predicted in cosmologies that include intense new classical sources such as first-order phase transitions, late-ending inflation, and dynamically active mesoscopic extra dimensions. LISA will provide the most sensitive direct probes of such phenomena near TeV energies or Terascale. LISA will also deeply probe the broadband background, and possibly bursts, from loops of cosmic superstrings predicted to form in current models of brane inflation.

Craig J. Hogan

2006-08-25T23:59:59.000Z

113

Constraining the Braneworld with Gravitational Wave Observations

Some braneworld models may have observable consequences that, if detected, would validate a requisite element of string theory. In the infinite Randall-Sundrum model (RS2), the AdS radius of curvature, l, of the extra dimension supports a single bound state of the massless graviton on the brane, thereby reproducing Newtonian gravity in the weak-field limit. However, using the AdS/CFT correspondence, it has been suggested that one possible consequence of RS2 is an enormous increase in Hawking radiation emitted by black holes. We utilize this possibility to derive two novel methods for constraining l via gravitational wave measurements. We show that the EMRI event rate detected by LISA can constrain l at the {approx}1 {mu}m level for optimal cases, while the observation of a single galactic black hole binary with LISA results in an optimal constraint of l{<=}5 {mu}m.

McWilliams, Sean T. [Gravitational Astrophysics Laboratory, NASA Goddard Space Flight Center, 8800 Greenbelt Road, Greenbelt Maryland 20771 (United States)

2010-04-09T23:59:59.000Z

114

Energy Contents of Gravitational Waves in Teleparallel Gravity

The conserved quantities, that are, gravitational energy-momentum and its relevant quantities are investigated for cylindrical and spherical gravitational waves in the framework of teleparallel equivalent of General Relativity using the Hamiltonian approach. For both cylindrical and spherical gravitational waves, we obtain definite energy and constant momentum. The constant momentum shows consistency with the results available in General Relativity and teleparallel gravity. The angular momentum for cylindrical and spherical gravitational waves also turn out to be constant. Further, we evaluate their gravitational energy-momentum fluxes and gravitational pressure.

M. Sharif; Sumaira Taj

2009-10-02T23:59:59.000Z

115

Correlation between Gamma-Ray bursts and Gravitational Waves

The cosmological origin of $\\gamma$-ray bursts (GRBs) is now commonly accepted and, according to several models for the central engine, GRB sources should also emit at the same time gravitational waves bursts (GWBs). We have performed two correlation searches between the data of the resonant gravitational wave detector AURIGA and GRB arrival times collected in the BATSE 4B catalog. No correlation was found and an upper limit \\bbox{$h_{\\text{RMS}} \\leq 1.5 \\times 10^{-18}$} on the averaged amplitude of gravitational waves associated with $\\gamma$-ray bursts has been set for the first time.

P. Tricarico; A. Ortolan; A. Solaroli; G. Vedovato; L. Baggio; M. Cerdonio; L. Taffarello; J. Zendri; R. Mezzena; G. A. Prodi; S. Vitale; P. Fortini; M. Bonaldi; P. Falferi

2001-01-05T23:59:59.000Z

116

Gravitational wave generation in power-law inflationary models

We investigate the generation of gravitational waves in power-law inflationary models. The energy spectrum of the gravitational waves is calculated using the method of continuous Bogoliubov coefficients. We show that, by looking at the interval of frequencies between 10^(-5) and 10^5 Hz and also at the GHz range, important information can be obtained, both about the inflationary period itself and about the thermalization regime between the end of inflation and the beginning of the radiation-dominated era. We thus deem the development of gravitational wave detectors, covering the MHz/GHz range of frequencies, to be an important task for the future.

Paulo M. Sá; Alfredo B. Henriques

2008-06-06T23:59:59.000Z

117

Quasar Proper Motions and Low-Frequency Gravitational Waves

We report observational upper limits on the mass-energy of the cosmological gravitational-wave background, from limits on proper motions of quasars. Gravitational waves with periods longer than the time span of observations produce a simple pattern of apparent proper motions over the sky, composed primarily of second-order transverse vector spherical harmonics. A fit of such harmonics to measured motions yields a 95%-confidence limit on the mass-energy of gravitational waves with frequencies <2e-9 Hz, of <0.11/h*h times the closure density of the universe.

Carl R. Gwinn; T. Marshall Eubanks; Ted Pyne; Mark Birkinshaw; Demetrios N. Matsakis

1996-10-12T23:59:59.000Z

118

Fast Gravitational Wave Radiometry using Data Folding

Gravitational Waves (GWs) from the early universe and unresolved astrophysical sources are expected to create a stochastic GW background (SGWB). The GW radiometer algorithm is well suited to probe such a background using data from ground based laser interferometric detectors. Radiometer analysis can be performed in different bases, e.g., isotropic, pixel or spherical harmonic. Each of these analyses possesses a common temporal symmetry which we exploit here to fold the whole dataset for every detector pair, typically a few hundred to a thousand days of data, to only one sidereal day, without any compromise in precision. We develop the algebra and a software pipeline needed to fold data, accounting for the effect of overlapping windows and non-stationary noise. We implement this on LIGO's fifth science run data and validate it by performing a standard anisotropic SGWB search on both folded and unfolded data. Folded data not only leads to orders of magnitude reduction in computation cost, but it results in a co...

Ain, Anirban; Mitra, Sanjit

2015-01-01T23:59:59.000Z

119

Techniques for improving the readout sensitivity of gravitational wave antennae

The detection of gravitational waves (GWs) from astrophysical sources shows promise as a new method to probe extremely energetic phenomena and test the strong field limit of the general theory of relativity. The era of the ...

Smith-Lefebvre, Nicolás de Mateo

2012-01-01T23:59:59.000Z

120

Polarized Gravitational Waves from Gamma-Ray Bursts

Significant gravitational wave emission is expected from gamma-ray bursts arising from compact stellar mergers, and possibly also from bursts associated with fast-rotating massive stellar core collapses. These models have in common a high angular rotation rate, and observations provide evidence for jet collimation of the photon emission, with properties depending on the polar angle, which may also be of relevance for X-ray flashes. Here we consider the gravitational wave emission and its polarization as a function of angle which is expected from such sources. We discuss possible correlations between the burst photon luminosity, or the delay between gravitational wave bursts and X-ray flashes, and the polarization degree of the gravitational waves.

Shiho Kobayashi; Peter Meszaros

2003-01-24T23:59:59.000Z

While these samples are representative of the content of NLE

they are not comprehensive nor are they the most current set.

We encourage you to perform a real-time search of NLE

to obtain the most current and comprehensive results.

121

Propagation of gravitational waves in the nonperturbative spinor vacuum

The propagation of gravitational waves on the background of a nonperturbative vacuum of a spinor field is considered. It is shown that there are several distinctive features in comparison with the propagation of plane gravitational waves through empty space: there exists the fixed phase difference between the $h_{yy,zz}$ and $h_{yz}$ components of the wave; the phase and group velocities of gravitational waves are not equal to the velocity of light; the group velocity is always less than the velocity of light; under some conditions the gravitational waves are either damped or absent; for given frequency, there exist two waves with different wave vectors. We also discuss the possibility of experimental verification of the obtained effects as a tool to investigate nonperurbative quantum field theories.

Vladimir Dzhunushaliev; Vladimir Folomeev

2014-09-02T23:59:59.000Z

122

Open Issues in the search for gravitational wave transients

The LIGO-Virgo network of kilometer-scale laser interferometric gravitational-wave detectors reached a major milestone with the successful operation of LIGO's fifth (S5) and Virgo's first (VSR1) science runs during 2005-2007. ...

Blackburn, Lindy L

2010-01-01T23:59:59.000Z

123

Search for gravitational waves from intermediate mass binary black holes

We present the results of a weakly modeled burst search for gravitational waves from mergers of nonspinning intermediate mass black holes in the total mass range 100–450??M? and with the component mass ratios between 1?1 ...

Barsotti, Lisa

124

Directed search for continuous gravitational waves from the Galactic center

We present the results of a directed search for continuous gravitational waves from unknown, isolated neutron stars in the Galactic center region, performed on two years of data from LIGO’s fifth science run from two LIGO ...

Aggarwal, Nancy

125

Gravitational wave detection using high precision pulsar observations

Pulsar timing experiments are reaching sufficient sensitivity to detect a postulated stochastic gravitational wave background generated by merging supermassive black hole systems in the cores of galaxies. We describe the techniques behind the pulsar timing detection method, provide current upper bounds on the amplitude of any gravitational wave background, describe theoretical models predicting the existence of such a background and highlight new techniques for providing a statistically rigorous detection of the background.

G. Hobbs

2008-02-10T23:59:59.000Z

126

Anisotropies in the gravitational-wave stochastic background

We consider anisotropies in the stochastic background of gravitational-waves (SBGW) arising from random fluctuations in the number of gravitational-wave sources. We first develop the general formalism which can be applied to different cosmological or astrophysical scenarios. We then apply this formalism to calculate the anisotropies of SBGW associated with the fluctuations in the number of cosmic string loops, considering both cosmic string cusps and kinks. We calculate the anisotropies as a function of angle and frequency.

Ölmez, S.; Mandic, V. [School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455 (United States); Siemens, X., E-mail: olmez@physics.umn.edu, E-mail: mandic@physics.umn.edu, E-mail: siemens@gravity.phys.uwm.edu [Center for Gravitation and Cosmology, University of Wisconsin-Milwaukee, Milwaukee, WI 53201 (United States)

2012-07-01T23:59:59.000Z

127

Gravitational waves from global second order phase transitions

Global second-order phase transitions are expected to produce scale-invariant gravitational wave spectra. In this manuscript we explore the dynamics of a symmetry-breaking phase transition using lattice simulations. We explicitly calculate the stochastic gravitational wave background produced during the transition and subsequent self-ordering phase. We comment on this signal as it compares to the scale-invariant spectrum produced during inflation.

Jr, John T. Giblin [Department of Physics, Kenyon College, 201 North College Rd, Gambier, OH 43022 (United States); Price, Larry R.; Siemens, Xavier; Vlcek, Brian, E-mail: giblinj@kenyon.edu, E-mail: larryp@caltech.edu, E-mail: siemens@gravity.phys.uwm.edu, E-mail: bvlcek@uwm.edu [Center for Gravitation and Cosmology, Department of Physics, University of Wisconsin-Milwaukee, P.O. Box 413, Milwaukee, WI 53201 (United States)

2012-11-01T23:59:59.000Z

128

A perturbative and gauge invariant treatment of gravitational wave memory

We present a perturbative treatment of gravitational wave memory. The coordinate invariance of Einstein's equations leads to a type of gauge invariance in perturbation theory. As with any gauge invariant theory, results are more clear when expressed in terms of manifestly gauge invariant quantities. Therefore we derive all our results from the perturbed Weyl tensor rather than the perturbed metric. We derive gravitational wave memory for the Einstein equations coupled to a general energy-momentum tensor that reaches null infinity.

Lydia Bieri; David Garfinkle

2014-04-03T23:59:59.000Z

129

High-Frequency Gravitational Waves from Hairy Black Holes

We investigated the stability of the spherically symmetric non-abelian (Bartnik-McKinnon) black hole solution of the SU(2) Einstein-Yang-Mills system using the multiple-scale analysis. It is found, in contrast with the vacuum situation, that a spherically symmetric oscillatory perturbation to second order cannot be constructed. The singular behavior of gravitational waves is induced by the coupling of the gravitational waves to the Yang-Mills waves.

Reinoud J. Slagter

1999-03-05T23:59:59.000Z

130

Gravitational-wave Science in the High School Classroom

This article describes a set of curriculum modifications designed to integrate gravitational-wave science into a high school physics or astronomy curriculum. Gravitational-wave scientists are on the verge of being able to detect extreme cosmic events, like the merger of two black holes, happening hundreds of millions of light years away. Their work has the potential to propel astronomy into a new era by providing an entirely new means of observing astronomical phenomena. Gravitational-wave science encompasses astrophysics, physics, engineering, and quantum optics. As a result, this curriculum exposes students to the interdisciplinary nature of science. It also provides an authentic context for students to learn about astrophysical sources, data analysis techniques, cutting-edge detector technology, and error analysis.

Benjamin Farr; GionMatthias Schelbert; Laura Trouille

2012-08-20T23:59:59.000Z

131

GRAVITATIONAL WAVES OF JET PRECESSION IN GAMMA-RAY BURSTS

The physical nature of gamma-ray bursts (GRBs) is believed to involve an ultra-relativistic jet. The observed complex structure of light curves motivates the idea of jet precession. In this work, we study the gravitational waves of jet precession based on neutrino-dominated accretion disks around black holes, which may account for the central engine of GRBs. In our model, the jet and the inner part of the disk may precess along with the black hole, which is driven by the outer part of the disk. Gravitational waves are therefore expected to be significant from this black-hole-inner-disk precession system. By comparing our numerical results with the sensitivity of some detectors, we find that it is possible for DECIGO and BBO to detect such gravitational waves, particularly for GRBs in the Local Group.

Sun Mouyuan; Liu Tong; Gu Weimin; Lu Jufu, E-mail: tongliu@xmu.edu.cn [Department of Physics and Institute of Theoretical Physics and Astrophysics, Xiamen University, Xiamen, Fujian 361005 (China)

2012-06-10T23:59:59.000Z

132

Detecting Beyond-Einstein Polarizations of Continuous Gravitational Waves

The direct detection of gravitational waves with the next generation detectors, like Advanced LIGO, provides the opportunity to measure deviations from the predictions of General Relativity. One such departure would be the existence of alternative polarizations. To measure these, we study a single detector measurement of a continuous gravitational wave from a triaxial pulsar source. We develop methods to detect signals of any polarization content and distinguish between them in a model independent way. We present LIGO S5 sensitivity estimates for 115 pulsars.

Isi, Maximiliano; Mead, Carver; Pitkin, Matthew

2015-01-01T23:59:59.000Z

133

Gauge Invariant Effective Stress-Energy Tensors for Gravitational Waves

It is shown that if a generalized definition of gauge invariance is used, gauge invariant effective stress-energy tensors for gravitational waves and other gravitational perturbations can be defined in a much larger variety of circumstances than has previously been possible. In particular it is no longer necessary to average the stress-energy tensor over a region of spacetime which is larger in scale than the wavelengths of the waves and it is no longer necessary to restrict attention to high frequency gravitational waves.

Paul R. Anderson

1996-09-09T23:59:59.000Z

134

Large scale EPR correlations and cosmic gravitational waves

We study how quantum correlations survive at large scales in spite of their exposition to stochastic backgrounds of gravitational waves. We consider Einstein-Podolski-Rosen (EPR) correlations built up on the polarizations of photon pairs and evaluate how they are affected by the cosmic gravitational wave background (CGWB). We evaluate the quantum decoherence of the EPR correlations in terms of a reduction of the violation of the Bell inequality as written by Clauser, Horne, Shimony and Holt (CHSH). We show that this decoherence remains small and that EPR correlations can in principle survive up to the largest cosmic scales.

B. Lamine; R. Hervé; M. -T. Jaekel; A. Lambrecht; S. Reynaud

2011-05-10T23:59:59.000Z

135

DC readout experiment in Enhanced LIGO

The two 4 km long gravitational wave detectors operated by the Laser Interferometer Gravitational-wave Observatory (LIGO) were modified in 2008 to read out the gravitational wave channel using the DC readout form of homodyne ...

Fricke, Tobin T

136

On the Unreasonable Effectiveness of post-Newtonian Theory in Gravitational-Wave Physics

The first indirect detection of gravitational waves involved a binary system of neutron stars. In the future, the first direct detection may also involve binary systems -- inspiralling and merging binary neutron stars or black holes. This means that it is essential to understand in full detail the two-body system in general relativity, a notoriously difficult problem with a long history. Post-Newtonian approximation methods are thought to work only under slow motion and weak field conditions, while numerical solutions of Einstein's equations are thought to be limited to the final merger phase. Recent results have shown that post-Newtonian approximations seem to remain unreasonably valid well into the relativistic regime, while advances in numerical relativity now permit solutions for numerous orbits before merger. It is now possible to envision linking post-Newtonian theory and numerical relativity to obtain a complete ``solution'' of the general relativistic two-body problem. These solutions will play a central role in detecting and understanding gravitational wave signals received by interferometric observatories on Earth and in space.

Clifford M. Will

2010-01-08T23:59:59.000Z

137

E-Print Network 3.0 - autonomous gravitational-wave burst Sample...

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Doctorale de Physique de la Rgion Summary: for gravitational waves associated with gamma-ray bursts in 2009-2010 LIGO-Virgo data Soutenue le 27 juin 2011... for gravitational wave...

138

Gravitational waves from known pulsars: results from the initial detector era

We present the results of searches for gravitational waves from a large selection of pulsars using data from the most recent science runs (S6, VSR2 and VSR4) of the initial generation of interferometric gravitational wave ...

Aggarwal, Nancy

139

First LIGO search for gravitational wave bursts from cosmic (super)strings

We report on a matched-filter search for gravitational wave bursts from cosmic string cusps using LIGO data from the fourth science run (S4) which took place in February and March 2005. No gravitational waves were detected ...

Zucker, Michael E.

140

Detecting gravitational waves from highly eccentric compact binaries

In dense stellar regions, highly eccentric binaries of black holes and neutron stars can form through various n-body interactions. Such a binary could emit a significant fraction of its binding energy in a sequence of largely isolated gravitational wave bursts prior to merger. Given expected black hole and neutron star masses, many such systems will emit these repeated bursts at frequencies within the sensitive band of contemporary ground-based gravitational wave detectors. Unfortunately, existing gravitational wave searches are ill-suited to detect these signals. In this work, we adapt a "power stacking" method to the detection of gravitational wave signals from highly eccentric binaries. We implement this method as an extension of the Q-transform, a projection onto a multiresolution basis of windowed complex exponentials that has previously been used to analyze data from the network of LIGO/Virgo detectors. Our method searches for excess power over an ensemble of time-frequency tiles. We characterize the performance of our method using Monte Carlo experiments with signals injected in simulated detector noise. Our results indicate that the power stacking method achieves substantially better sensitivity to eccentric binary signals than existing localized burst searches.

Kai Sheng Tai; Sean T. McWilliams; Frans Pretorius

2014-03-30T23:59:59.000Z

While these samples are representative of the content of NLE

they are not comprehensive nor are they the most current set.

We encourage you to perform a real-time search of NLE

to obtain the most current and comprehensive results.

141

Propagation of Gravitational Waves in Generalized TeVeS

Efforts are underway to improve the design and sensitivity of gravitational waves detectors, with the hope that the next generation of these detectors will observe a gravitational wave signal. Such a signal will not only provide information on dynamics in the strong gravity regime that characterizes potential sources of gravitational waves, but will also serve as a decisive test for alternative theories of gravitation that are consistent with all other current experimental observations. We study the linearized theory of the tensor-vector-scalar theory of gravity (TeVeS) with generalized vector action, an alternative theory of gravitation designed to explain the apparent deficit of visible matter in galaxies and clusters of galaxies without postulating yet undetected dark matter. We find the polarization states and propagation speeds for gravitational waves in vacuum, and show that in addition to the usual transverse-traceless propagation modes, there are two more transverse modes and two trace modes. Additionally, the propagation speeds are different from c.

Eva Sagi

2010-01-11T23:59:59.000Z

142

We present the results of a search for gravitational-wave bursts associated with 137 gamma-ray bursts (GRBs) that were detected by satellite-based gamma-ray experiments during the fifth LIGO science run and first Virgo science run. The data used in this analysis were collected from 2005 November 4 to 2007 October 1, and most of the GRB triggers were from the Swift satellite. The search uses a coherent network analysis method that takes into account the different locations and orientations of the interferometers at the three LIGO-Virgo sites. We find no evidence for gravitational-wave burst signals associated with this sample of GRBs. Using simulated short-duration (<1 s) waveforms, we set upper limits on the amplitude of gravitational waves associated with each GRB. We also place lower bounds on the distance to each GRB under the assumption of a fixed energy emission in gravitational waves, with typical limits of D ~ 15 Mpc (E_GW^iso / 0.01 M_o c^2)^1/2 for emission at frequencies around 150 Hz, where the LIGO-Virgo detector network has best sensitivity. We present astrophysical interpretations and implications of these results, and prospects for corresponding searches during future LIGO-Virgo runs.

LIGO Scientific Collaboration; Virgo Collaboration; B. P. Abbott; R. Abbott; F. Acernese; R. Adhikari; P. Ajith; B. Allen; G. Allen; M. Alshourbagy; R. S. Amin; S. B. Anderson; W. G. Anderson; F. Antonucci; S. Aoudia; M. A. Arain; M. Araya; H. Armandula; P. Armor; K. G. Arun; Y. Aso; S. Aston; P. Astone; P. Aufmuth; C. Aulbert; S. Babak; P. Baker; G. Ballardin; S. Ballmer; C. Barker; D. Barker; F. Barone; B. Barr; P. Barriga; L. Barsotti; M. Barsuglia; M. A. Barton; I. Bartos; R. Bassiri; M. Bastarrika; Th. S. Bauer; B. Behnke; M. Beker; M. Benacquista; J. Betzwieser; P. T. Beyersdorf; S. Bigotta; I. A. Bilenko; G. Billingsley; S. Birindelli; R. Biswas; M. A. Bizouard; E. Black; J. K. Blackburn; L. Blackburn; D. Blair; B. Bland; C. Boccara; T. P. Bodiya; L. Bogue; F. Bondu; L. Bonelli; R. Bork; V. Boschi; S. Bose; L. Bosi; S. Braccini; C. Bradaschia; P. R. Brady; V. B. Braginsky; J. E. Brau; D. O. Bridges; A. Brillet; M. Brinkmann; V. Brisson; C. Van Den Broeck; A. F. Brooks; D. A. Brown; A. Brummit; G. Brunet; R. Budzy?ski; T. Bulik; A. Bullington; H. J. Bulten; A. Buonanno; O. Burmeister; D. Buskulic; R. L. Byer; L. Cadonati; G. Cagnoli; E. Calloni; J. B. Camp; E. Campagna; J. Cannizzo; K. C. Cannon; B. Canuel; J. Cao; F. Carbognani; L. Cardenas; S. Caride; G. Castaldi; S. Caudill; M. Cavagliŕ; F. Cavalier; R. Cavalieri; G. Cella; C. Cepeda; E. Cesarini; T. Chalermsongsak; E. Chalkley; P. Charlton; E. Chassande-Mottin; S. Chatterji; S. Chelkowski; Y. Chen; A. Chincarini; N. Christensen; C. T. Y. Chung; D. Clark; J. Clark; J. H. Clayton; F. Cleva; E. Coccia; T. Cokelaer; C. N. Colacino; J. Colas; A. Colla; M. Colombini; R. Conte; D. Cook; T. R. C. Corbitt; C. Corda; N. Cornish; A. Corsi; J. -P. Coulon; D. Coward; D. C. Coyne; J. D. E. Creighton; T. D. Creighton; A. M. Cruise; R. M. Culter; A. Cumming; L. Cunningham; E. Cuoco; S. L. Danilishin; S. D'Antonio; K. Danzmann; A. Dari; V. Dattilo; B. Daudert; M. Davier; G. Davies; E. J. Daw; R. Day; R. De Rosa; D. DeBra; J. Degallaix; M. del Prete; V. Dergachev; S. Desai; R. DeSalvo; S. Dhurandhar; L. Di Fiore; A. Di Lieto; M. Di Paolo Emilio; A. Di Virgilio; M. Díaz; A. Dietz; F. Donovan; K. L. Dooley; E. E. Doomes; M. Drago; R. W. P. Drever; J. Dueck; I. Duke; J. -C. Dumas; J. G. Dwyer; C. Echols; M. Edgar; M. Edwards; A. Effler; P. Ehrens; E. Espinoza; T. Etzel; M. Evans; T. Evans; V. Fafone; S. Fairhurst; Y. Faltas; Y. Fan; D. Fazi; H. Fehrmann; I. Ferrante; F. Fidecaro; L. S. Finn; I. Fiori; R. Flaminio; K. Flasch; S. Foley; C. Forrest; N. Fotopoulos; J. -D. Fournier; J. Franc; A. Franzen; S. Frasca; F. Frasconi; M. Frede; M. Frei; Z. Frei; A. Freise; R. Frey; T. Fricke; P. Fritschel; V. V. Frolov; M. Fyffe; V. Galdi; L. Gammaitoni; J. A. Garofoli; F. Garufi; G. Gemme; E. Genin; A. Gennai; I. Gholami; J. A. Giaime; S. Giampanis; K. D. Giardina; A. Giazotto; K. Goda; E. Goetz; L. M. Goggin; G. González; M. L. Gorodetsky; S. Goeßzetler; S. Goßler; R. Gouaty; M. Granata; V. Granata; A. Grant; S. Gras; C. Gray; M. Gray; R. J. S. Greenhalgh; A. M. Gretarsson; C. Greverie; F. Grimaldi; R. Grosso; H. Grote; S. Grunewald; M. Guenther; G. Guidi; E. K. Gustafson; R. Gustafson; B. Hage; J. M. Hallam; D. Hammer; G. D. Hammond; C. Hanna; J. Hanson; J. Harms; G. M. Harry; I. W. Harry; E. D. Harstad; K. Haughian; K. Hayama; J. Heefner; H. Heitmann; P. Hello; I. S. Heng; A. Heptonstall; M. Hewitson; S. Hild; E. Hirose; D. Hoak; K. A. Hodge; K. Holt; D. J. Hosken; J. Hough; D. Hoyland; D. Huet; B. Hughey; S. H. Huttner; D. R. Ingram; T. Isogai; M. Ito; A. Ivanov; P. Jaranowski; B. Johnson; W. W. Johnson; D. I. Jones; G. Jones; R. Jones; L. Sancho de la Jordana; L. Ju; P. Kalmus; V. Kalogera; S. Kandhasamy; J. Kanner; D. Kasprzyk; E. Katsavounidis; K. Kawabe; S. Kawamura; F. Kawazoe; W. Kells; D. G. Keppel; A. Khalaidovski; F. Y. Khalili; R. Khan; E. Khazanov; P. King; J. S. Kissel; S. Klimenko; K. Kokeyama; V. Kondrashov; R. Kopparapu; S. Koranda; I. Kowalska; D. Kozak; B. Krishnan; A. Królak; R. Kumar; P. Kwee; P. La Penna; P. K. Lam; M. Landry; B. Lantz; A. Lazzarini; H. Lei; M. Lei; N. Leindecker; I. Leonor; N. Leroy; N. Letendre; C. Li; H. Lin; P. E. Lindquist; T. B. Littenberg; N. A. Lockerbie; D. Lodhia; M. Longo; M. Lorenzini; V. Loriette; M. Lormand; G. Losurdo; P. Lu; M. Lubinski; A. Lucianetti; H. Lück; B. Machenschalk; M. MacInnis; J. -M. Mackowski; M. Mageswaran; K. Mailand; E. Majorana; N. Man; I. Mandel; V. Mandic; M. Mantovani; F. Marchesoni; F. Marion; S. Márka; Z. Márka; A. Markosyan; J. Markowitz; E. Maros; J. Marque; F. Martelli; I. W. Martin; R. M. Martin; J. N. Marx; K. Mason; A. Masserot; F. Matichard; L. Matone; R. A. Matzner; N. Mavalvala; R. McCarthy; D. E. McClelland; S. C. McGuire; M. McHugh; G. McIntyre; D. J. A. McKechan; K. McKenzie; M. Mehmet; A. Melatos; A. C. Melissinos; G. Mendell; D. F. Menéndez

2010-04-07T23:59:59.000Z

143

We present the results of a search for short-duration gravitational-wave bursts associated with 39 gamma-ray bursts (GRBs) detected by gamma-ray satellite experiments during LIGO's S2, S3, and S4 science runs. The search involves calculating the crosscorrelation between two interferometer data streams surrounding the GRB trigger time. We search for associated gravitational radiation from single GRBs, and also apply statistical tests to search for a gravitational-wave signature associated with the whole sample. For the sample examined, we find no evidence for the association of gravitational radiation with GRBs, either on a single-GRB basis or on a statistical basis. Simulating gravitational-wave bursts with sine-gaussian waveforms, we set upper limits on the root-sum-square of the gravitational-wave strain amplitude of such waveforms at the times of the GRB triggers. We also demonstrate how a sample of several GRBs can be used collectively to set constraints on population models. The small number of GRBs and the significant change in sensitivity of the detectors over the three runs, however, limits the usefulness of a population study for the S2, S3, and S4 runs. Finally, we discuss prospects for the search sensitivity for the ongoing S5 run, and beyond for the next generation of detectors.

LIGO Scientific Collaboration

2008-02-01T23:59:59.000Z

144

We present the results of a search for short-duration gravitational-wave bursts associated with 39 gamma-ray bursts (GRBs) detected by gamma-ray satellite experiments during LIGO's S2, S3, and S4 science runs. The search involves calculating the crosscorrelation between two interferometer data streams surrounding the GRB trigger time. We search for associated gravitational radiation from single GRBs, and also apply statistical tests to search for a gravitational-wave signature associated with the whole sample. For the sample examined, we find no evidence for the association of gravitational radiation with GRBs, either on a single-GRB basis or on a statistical basis. Simulating gravitational-wave bursts with sine-gaussian waveforms, we set upper limits on the root-sum-square of the gravitational-wave strain amplitude of such waveforms at the times of the GRB triggers. We also demonstrate how a sample of several GRBs can be used collectively to set constraints on population models. The small number of GRBs and ...

Abbott, B; Adhikari, R; Agresti, J; Ajith, P; Allen, B; Amin, R; Anderson, S B; Anderson, W G; Arain, M; Araya, M; Armandula, H; Ashley, M; Aston, S; Aufmuth, P; Aulbert, C; Babak, S; Ballmer, S; Bantilan, H; Barish, B C; Barker, C; Barker, D; Barr, B; Barriga, P; Barton, M A; Bayer, K; Belczynski, K; Berukoff, S J; Betzwieser, J; Beyersdorf, P T; Bhawal, B; Bilenko, I A; Billingsley, G; Biswas, R; Black, E; Blackburn, K; Blackburn, L; Blair, D; Bland, B; Bogenstahl, J; Bogue, L; Bork, R; Boschi, V; Bose, S; Brady, P R; Braginsky, V B; Brau, J E; Brinkmann, M; Brooks, A; Brown, D A; Bullington, A; Bunkowski, A; Buonanno, A; Burmeister, O; Busby, D; Butler, W E; Byer, R L; Cadonati, L; Cagnoli, G; Camp, J B; Cannizzo, J; Cannon, K; Cantley, C A; Cao, J; Cardenas, L; Carter, K; Casey, M M; Castaldi, G; Cepeda, C; Chalkey, E; Charlton, P; Chatterji, S; Chelkowski, S; Chen, Y; Chiadini, F; Chin, D; Chin, E; Chow, J; Christensen, N; Clark, J; Cochrane, P; Cokelaer, T; Colacino, C N; Coldwell, R; Coles, M; Conte, R; Cook, D; Corbitt, T; Coward, D; Coyne, D; Creighton, J D E; Creighton, T D; Croce, R P; Crooks, D R M; Cruise, A M; Csatorday, P; Cumming, A; Dalrymple, J; D'Ambrosio, E; Danzmann, K; Davies, G; Daw, E; De Bra, D; Degallaix, J; Degree, M; Delker, T; Demma, T; Dergachev, V; Desai, S; DeSalvo, R; Dhurandhar, S; Díaz, M; Dickson, J; Di Credico, A; Diederichs, G; Dietz, A; Ding, H; Doomes, E E; Drever, R W P; Dumas, J C; Dupuis, R J; Dwyer, J G; Ehrens, P; Espinoza, E; Etzel, T; Evans, M; Evans, T; Fairhurst, S; Fan, Y; Fazi, D; Fejer, M M; Finn, L S; Fiumara, V; Fotopoulos, N; Franzen, A; Franzen, K Y; Freise, A; Frey, R; Fricke, T; Fritschel, P; Frolov, V V; Fyffe, M; Galdi, V; Ganezer, K S; Garofoli, J; Gholami, I; Giaime, J A; Giampanis, S; Giardina, K D; Goda, K; Goetz, E; Goggin, L; González, G; Gossler, S; Grant, A; Gras, S; Gray, C; Gray, M; Greenhalgh, J; Gretarsson, A M; Grosso, R; Grote, H; Grünewald, S; Günther, M; Gustafson, R; Hage, B; Hammer, D; Hanna, C; Hanson, J; Harms, J; Harry, G; Harstad, E; Hayler, T; Heefner, J; Heinzel, G; Heng, I S; Heptonstall, A; Heurs, M; Hewitson, M; Hild, S; Hirose, E; Hoak, D; Hosken, D; Hough, J; Howell, E; Hoyland, D; Huttner, S H; Ingram, D; Innerhofer, E; Ito, M; Itoh, Y; Ivanov, A; Jackrel, D; Jennrich, O; Johnson, B; Johnson, W W; Johnston, W R; Jones, D I; Jones, G; Jones, R; Ju, L; Kalmus, Peter Ignaz Paul; Kalogera, V; Kasprzyk, D; Katsavounidis, E; Kawabe, K; Kawamura, S; Kawazoe, F; Kells, W; Keppel, D G; Khalili, F Ya; Killow, C J; Kim, C; King, P; Kissel, J S; Klimenko, S; Kokeyama, K; Kondrashov, V; Kopparapu, R K; Kozak, D; Krishnan, B; Kwee, P; Lam, P K; Landry, M; Lantz, B; Lazzarini, A; Lee, B; Lei, M; Leiner, J; Leonhardt, V; Leonor, I; Libbrecht, K; Libson, A; Lindquist, P; Lockerbie, N A; Logan, J; Longo, M; Lormand, M; Lubinski, M; Luck, H; Machenschalk, B; MacInnis, M; Mageswaran, M; Mailand, K; Malec, M; Mandic, V; Marano, S; Marka, S; Markowitz, J; Maros, E; Martin, I; Marx, J N; Mason, K; Matone, L; Matta, V; Mavalvala, N; McCarthy, R; McClelland, D E; McGuire, S C; McHugh, M; McKenzie, K; McNabb, J W C; McWilliams, S; Meier, T; Melissinos, A; Mendell, G; Mercer, R A; Meshkov, S; Messaritaki, E; Messenger, C J; Meyers, D; Mikhailov, E; Mitra, S; Mitrofanov, V P; Mitselmakher, G; Mittleman, R; Miyakawa, O; Mohanty, S; Moreno, G; Mossavi, K; Mow Lowry, C; Moylan, A; Mudge, D; Müller, G; Mukherjee, S; Muller-Ebhardt, H; Munch, J; Murray, P; Myers, E; Myers, J; Nagano, S; Nash, T; Newton, G; Nishizawa, A; Nocera, F; Numata, K; Nutzman, P; O'Reilly, B; O'Shaughnessy, R; Ottaway, D J; Overmier, H; Owen, B J; Pan, Y; Papa, M A; Parameshwaraiah, V; Parameswariah, C; Patel, P; Pedraza, M; Penn, S; Pierro, V; Pinto, I M; Pitkin, M; Pletsch, H; Plissi, M V; Postiglione, F; Prix, R; Quetschke, V; Raab, F; Rabeling, D; Radkins, H; Rahkola, R; Rainer, N; Rakhmanov, M; Ramsunder, M; Rawlins, K; Ray-Majumder, S; Re, V; Regimbau, T; Rehbein, H; Reid, S; Reitze, D H; Ribichini, L; Richman, S; Riesen, R; Riles, K; Rivera, B; Robertson, N A; Robinson, C; Robinson, E L; Roddy, S; Rodríguez, A; Rogan, A M; Rollins, J; Romano, J D; Romie, J; Rong, H; Route, R; Rowan, S; Rüdiger, A; Ruet, L; Russell, P; Ryan, K; Sakata, S; Samidi, M; Sancho de la Jordana, L; Sandberg, V; Sanders, G H; Sannibale, V; Saraf, S; Sarin, P; Sathyaprakash, B S; Sato, S; Saulson, P R; Savage, R; Savov, P; Sazonov, A; Schediwy, S; Schilling, R; Schnabel, R; Schofield, R; Schutz, B F; Schwinberg, P; Scott, S M; Searle, A C; Sears, B; Seifert, F; Sellers, D; Sengupta, A S; Shawhan, P; Shoemaker, D H; Sibley, A; Sidles, J A; Siemens, X; Sigg, D; Sinha, S; Sintes, A M; Slagmolen, B J J; Slutsky, J; Smith, J R; Smith, M R; Somiya, K; Strain, K A; Strand, N E; Strom, D M; Stuver, A; Summerscales, T Z; Sun, K X; Sung, M; Sutton, P J; Sylvestre, J; Takahashi, H; Takamori, A

2007-01-01T23:59:59.000Z

145

We study future observational constraints on cosmic string parameters from various types of next-generation experiments: direct detection of gravitational waves (GWs), pulsar timing array, and the cosmic microwave background (CMB). We consider both GW burst and stochastic GW background searches by ground- and space-based interferometers as well as GW background detection in pulsar timing experiments. We also consider cosmic string contributions to the CMB temperature and polarization anisotropies. These different types of observations offer independent probes of cosmic strings and may enable us to investigate cosmic string properties if the signature is detected. In this paper, we evaluate the power of future experiments to constrain cosmic string parameters, such as the string tension Gmu, the initial loop size alpha, and the reconnection probability p, by performing Fisher information matrix calculations. We find that combining the information from the different types of observations breaks parameter degeneracies and provides more stringent constraints on the parameters. We also find future space-borne interferometers independently provide a highly precise determination of the parameters.

Sachiko Kuroyanagi; Koichi Miyamoto; Toyokazu Sekiguchi; Keitaro Takahashi; Joseph Silk

2013-02-19T23:59:59.000Z

146

The first direct detection of gravitational waves (GW) by the ground-based interferometers is expected to occur within the next few years. These interferometers will detect the mergers of compact object binaries composed of neutron stars and/or black holes to a fiducial distance of ~200 Mpc and a localization region of ~100 sq. deg. To maximize the science gains from such GW detections it is essential to identify electromagnetic (EM) counterparts. The most promising such counterpart is optical/IR emission powered by the radioactive decay of r-process elements synthesized in the neutron-rich merger ejecta - a "kilonova". Here we present detailed simulated observations that encompass a range of strategies for kilonova searches during GW follow-up. We assess both the detectability of kilonovae and our ability to distinguish them from a wide range of contaminating transients. We find that if pre-existing template images for the localization region are available, then nightly observations to a depth of i=24 mag an...

Cowperthwaite, P S

2015-01-01T23:59:59.000Z

147

First upper limits from LIGO on gravitational wave bursts

We report on a search for gravitational wave bursts using data from the first science run of the LIGO detectors. Our search focuses on bursts with durations ranging from 4 ms to 100 ms, and with significant power in the LIGO sensitivity band of 150 to 3000 Hz. We bound the rate for such detected bursts at less than 1.6 events per day at 90% confidence level. This result is interpreted in terms of the detection efficiency for ad hoc waveforms (Gaussians and sine-Gaussians) as a function of their root-sum-square strain h{sub rss}; typical sensitivities lie in the range h{sub rss} {approx} 10{sup -19} - 10{sup -17} strain/{radical}Hz, depending on waveform. We discuss improvements in the search method that will be applied to future science data from LIGO and other gravitational wave detectors.

B. Abbott et al.

2004-03-09T23:59:59.000Z

148

On Investigating EMD Parameters to Search for Gravitational Waves

The Hilbert-Huang transform (HHT) is a novel, adaptive approach to time series analysis. It does not impose a basis set on the data or otherwise make assumptions about the data form, and so the time--frequency decomposition is not limited by spreading due to uncertainty. Because of the high resolution of the time--frequency, we investigate the possibility of the application of the HHT to the search for gravitational waves. It is necessary to determine some parameters in the empirical mode decomposition (EMD), which is a component of the HHT, and in this paper we propose and demonstrate a method to determine the optimal values of the parameters to use in the search for gravitational waves.

Hirotaka Takahashi; Ken-ichi Oohara; Masato Kaneyama; Yuta Hiranuma; Jordan B Camp

2013-06-23T23:59:59.000Z

149

Inhomogeneous High Frequency Expansion-Free Gravitational Waves

We describe a natural inhomogeneous generalization of high frequency plane gravitational waves. The waves are high frequency waves of the Kundt type whose null propagation direction in space-time has vanishing expansion, twist and shear but is not covariantly constant. The introduction of a cosmological constant is discussed in some detail and a comparison is made with high frequency gravity waves having wave fronts homeomorphic to 2-spheres.

C. Barrabes; P. A. Hogan

2007-06-18T23:59:59.000Z

150

How to Estimate Energy Lost to Gravitational Waves (revised)

The energy--momentum radiated in gravitational waves by an isolated source is given by a formula of Bondi. This formula is highly non--local: the energy--momentum is not given as the integral of a well--defined local density. It has therefore been unclear whether the Bondi formula can be used to get information from gravity--wave measurements. In this note, we obtain, from local knowledge of the radiation field, a lower bound on the Bondi flux.

Adam D. Helfer

1993-07-19T23:59:59.000Z

151

Plasma waves driven by gravitational waves in an expanding universe

In a Friedmann-Robertson-Walker (FRW) cosmological model with zero spatial curvature, we consider the interaction of the gravitational waves with the plasma in the presence of a weak magnetic field. Using the relativistic hydromagnetic equations it is verified that large amplitude magnetosonic waves are excited, assuming that both, the gravitational field and the weak magnetic field do not break the homogeneity and isotropy of the considered FRW spacetime.

D. B. Papadopoulos

2002-05-22T23:59:59.000Z

152

An alternative method for calculating the energy of gravitational waves

In the expansive nondecelerative universe model, creation of matter occurs due to which the Vaidya metrics is applied. This fact allows for localizing gravitational energy and calculating the energy of gravitational waves using an approach alternative to the well established procedure based on quadrupole formula. Rationalization of the gradual increase in entropy of the Universe using relation describing the total curvature of space-time is given too.

Miroslav Sukenik; Jozef Sima

1999-09-21T23:59:59.000Z

153

Harmonic generation of gravitational wave induced Alfven waves

Here we consider the nonlinear evolution of Alfven waves that have been excited by gravitational waves from merging binary pulsars. We derive a wave equation for strongly nonlinear and dispersive Alfven waves. Due to the weak dispersion of the Alfven waves, significant wave steepening can occur, which in turn implies strong harmonic generation. We find that the harmonic generation is saturated due to dispersive effects, and use this to estimate the resulting spectrum. Finally we discuss the possibility of observing the above process.

Mats Forsberg; Gert Brodin

2007-11-26T23:59:59.000Z

154

Projected Constraints on Lorentz-Violating Gravity with Gravitational Waves

Gravitational waves are excellent tools to probe the foundations of General Relativity in the strongly dynamical and non-linear regime. One such foundation is Lorentz symmetry, which can be broken in the gravitational sector by the existence of a preferred time direction, and thus, a preferred frame at each spacetime point. This leads to a modification in the orbital decay rate of binary systems, and also in the generation and chirping of their associated gravitational waves. We here study whether waves emitted in the late, quasi-circular inspiral of non-spinning, neutron star binaries can place competitive constraints on two proxies of gravitational Lorentz-violation: Einstein-\\AE{}ther theory and khronometric gravity. We model the waves in the small-coupling (or decoupling) limit and in the post-Newtonian approximation, by perturbatively solving the field equations in small deformations from General Relativity and in the small-velocity/weak-gravity approximation. We assume a gravitational wave consistent with General Relativity has been detected with second- and third-generation, ground-based detectors, and with the proposed space-based mission, DECIGO, with and without coincident electromagnetic counterparts. Without a counterpart, a detection consistent with General Relativity of neutron star binaries can only place competitive constraints on gravitational Lorentz violation when using future, third-generation or space-based instruments. On the other hand, a single counterpart is enough to place constraints that are 10 orders of magnitude more stringent than current binary pulsar bounds, even when using second-generation detectors. This is because Lorentz violation forces the group velocity of gravitational waves to be different from that of light, and this difference can be very accurately constrained with coincident observations.

Devin Hansen; Nicolas Yunes; Kent Yagi

2014-12-12T23:59:59.000Z

155

Detuned Twin-Signal-Recycling for ultra-high precision interferometers

We propose a new interferometer technique for high precision phase measurements such as those in gravitational wave detection. The technique utilizes a pair of optically coupled resonators that provides identical resonance conditions for the upper as well the lower phase modulation signal sidebands. This symmetry significantly reduces the noise spectral density in a wide frequency band compared with single sideband recycling topologies of current and planned gravitational wave detectors. Furthermore the application of squeezed states of light becomes less demanding.

Andre Thuering; Roman Schnabel; Harald Lueck; Karsten Danzmann

2007-07-03T23:59:59.000Z

156

Characterization of an advanced LIGO quadruple pendulum system

The Laser Interferometer Gravitational-wave Observatory (LIGO) measures relative displacements of the interferometer mirrors induced by passing gravitational waves (GWs). At low frequencies, typically below 30 Hz, seismic ...

Thomas, Andrew C. (Andrew Christopher), 1981-

2004-01-01T23:59:59.000Z

157

Detecting gravitational waves from mountains on neutron stars in the Advanced Detector Era

Rapidly rotating Neutron Stars (NSs) in Low Mass X-ray Binaries (LMXBs) are thought to be interesting sources of Gravitational Waves (GWs) for current and next generation ground based detectors, such as Advanced LIGO and the Einstein Telescope. The main reason is that many of the NS in these systems appear to be spinning well below their Keplerian breakup frequency, and it has been suggested that torques associated with GW emission may be setting the observed spin period. This assumption has been used extensively in the literature to assess the strength of the likely gravitational wave signal. There is now, however, a significant amount of theoretical and observation work that suggests that this may not be the case, and that GW emission is unlikely to be setting the spin equilibrium period in many systems. In this paper we take a different starting point and predict the GW signal strength for two physical mechanisms that are likely to be at work in LMXBs: crustal mountains due to thermal asymmetries and magnetically confined mountains. We find that thermal crustal mountains in transient LMXBs are unlikely to lead to detectable GW emission, while persistent systems are good candidates for detection by Advanced LIGO and by the Einstein Telescope. Detection prospects are pessimistic for the magnetic mountain case, unless the NS has a buried magnetic field of $B\\approx 10^{12}$ G, well above the typically inferred exterior dipole fields of these objects. Nevertheless, if a system were to be detected by a GW observatory, cyclotron resonant scattering features in the X-ray emission could be used to distinguish between the two different scenarios.

Brynmor Haskell; Maxim Priymak; Alessandro Patruno; Manuel Oppenoorth; Andrew Melatos; Paul Lasky

2015-01-24T23:59:59.000Z

158

Modeling a nonperturbative spinor vacuum interacting with a strong gravitational wave

We consider the propagation of strong gravitational waves interacting with a nonperturbative vacuum of spinor fields. To described the latter, we suggest an approximate model. The corresponding Einstein equation has the form of the Schr\\"odinger equation. Its gravitational-wave solution is analogous to the solution of the Schr\\"odinger equation for an electron moving in a periodic potential. The general solution for the periodic gravitational waves is found. The analog of the Kronig-Penney model for gravitational waves is considered. It is shown that the suggested gravitational-wave model permits the existence of weak electric charge and current densities concomitant with the gravitational wave. Based on this observation, a possible experimental verification of the model is suggested.

Vladimir Dzhunushaliev; Vladimir Folomeev

2015-03-15T23:59:59.000Z

159

Modeling a nonperturbative spinor vacuum interacting with a strong gravitational wave

We consider the propagation of strong gravitational waves interacting with a nonperturbative vacuum of spinor fields. To described the latter, we suggest an approximate model. The corresponding Einstein equation has the form of the Schr\\"odinger equation. Its gravitational-wave solution is analogous to the solution of the Schr\\"odinger equation for an electron moving in a periodic potential. The general solution for the periodic gravitational waves is found. The analog of the Kronig-Penney model for gravitational waves is considered. It is shown that the suggested gravitational-wave model permits the existence of weak electric charge and current densities concomitant with the gravitational wave. Based on this observation, a possible experimental verification of the model is suggested.

Dzhunushaliev, Vladimir

2015-01-01T23:59:59.000Z

160

Gravitational Waves from Coalescing Binary Black Holes: Theoretical and Experimental Challenges

A network of ground-based interferometric gravitational wave detectors (LIGO/VIRGO/GEO/...) is currently taking data near its planned sensitivity. Coalescing black hole binaries are among the most promising, and most exciting, gravitational wave sources for these detectors. The talk will review the theoretical and experimental challenges that must be met in order to successfully detect gravitational waves from coalescing black hole binaries, and to be able to reliably measure the physical parameters of the source (masses, spins, ...).

None

2011-10-06T23:59:59.000Z

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they are not comprehensive nor are they the most current set.

We encourage you to perform a real-time search of NLE

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161

Gravitational-wave modes from precessing black-hole binaries

Gravitational waves from precessing black-hole binaries exhibit features that are absent in nonprecessing systems. The most prominent of these is a parity-violating asymmetry that beams energy and linear momentum preferentially along or opposite to the orbital angular momentum, leading to recoil of the binary. The asymmetry will appear as amplitude and phase modulations at the orbital frequency. For strongly precessing systems, it accounts for at least 3% amplitude modulation for binaries in the sensitivity band of ground-based gravitational-wave detectors, and can exceed 50% for massive systems. Such asymmetric features are also clearly visible when the waves are decomposed into modes of spin-weighted spherical harmonics, and are inherent in the waves themselves---rather than resulting from residual eccentricity in numerical simulations, or from mode-mixing due to precession. In particular, there is generically no instantaneous frame for which the mode decomposition will have any symmetry. We introduce a method to simplify the expressions for waveforms given in analytical relativity, which can be used to combine existing high-order waveforms for nonprecessing systems with expressions for the precessing contributions, leading to improved accuracy and a unified treatment of precessing and nonprecessing binaries. Using this method, it is possible to clarify the nature and the origins of the asymmetries and show the effects of asymmetry on recoils more clearly. We present post-Newtonian (PN) expressions for the waveform modes that include these terms, complete to the relative 2PN level in spin (proportional to $v^4/c^4$ times a certain combination of the spins). Comparing the results of those expressions to numerical results, we find good qualitative agreement. We also demonstrate how these expressions can be used to efficiently calculate waveforms for gravitational-wave astronomy.

Michael Boyle; Lawrence E. Kidder; Serguei Ossokine; Harald P. Pfeiffer

2014-09-22T23:59:59.000Z

162

Low-Frequency Sources of Gravitational Waves: A Tutorial

Gravitational wave detectors in space, particularly the LISA project, can study a rich variety of astronomical systems whose gravitational radiation is not detectable from the ground, because it is emitted in the low-frequency gravitational wave band (0.1 mHz to 1 Hz) that is inaccessible to ground-based detectors. Sources include binary systems in our Galaxy and massive black holes in distant galaxies. The radiation from many of these sources will be so strong that it will be possible to make remarkably detailed studies of the physics of the systems. These studies will have importance both for astrophysics (most notably in binary evolution theory and models for active galaxies) and for fundamental physics. In particular, it should be possible to make decisive measurements to confirm the existence of black holes and to test, with accuracies better than 1%, general relativity's description of them. Other observations can have fundamental implications for cosmology and for physical theories of the unification of forces. In order to understand these conclusions, one must know how to estimate the gravitational radiation produced by different sources. In the first part of this lecture I review the dynamics of gravitational wave sources, and I derive simple formulas for estimating wave amplitudes and the reaction effects on sources of producing this radiation. With these formulas one can estimate, usually to much better than an order of magnitude, the physics of most of the interesting low-frequency sources. In the second part of the lecture I use these estimates to discuss, in the context of the expected sensitivity of LISA, what we can learn by from observations of binary systems, massive black holes, and the early Universe itself.

B. F. Schutz

1997-10-15T23:59:59.000Z

163

Searches for gravitational-wave transients from binary black hole coalescences typically rely on one of two approaches: matched filtering with templates and morphology-independent excess power searches. Multiple algorithmic implementations in the analysis of data from the first generation of ground-based gravitational wave interferometers have used different strategies for the suppression of non-Gaussian noise transients, and targeted different regions of the binary black hole parameter space. In this paper we compare the sensitivity of three such algorithms: matched filtering with full coalescence templates, matched filtering with ringdown templates and a morphology-independent excess power search. The comparison is performed at a fixed false alarm rate and relies on Monte-carlo simulations of binary black hole coalescences for spinning, non-precessing systems with total mass 25-350 solar mass, which covers the parameter space of stellar mass and intermediate mass black hole binaries. We find that in the mass range of 25 -100 solar mass the sensitive distance of the search, marginalized over source parameters, is best with matched filtering to full waveform templates, to within 10 percent at a false alarm rate of 3 events per year. In the mass range of 100-350 solar mass, the same comparison favors the morphology-independent excess power search to within 20 percent. The dependence on mass and spin is also explored.

Satya Mohapatra; Laura Cadonati; Sarah Caudill; James Clark; Chad Hanna; Sergey Klimenko; Chris Pankow; Ruslan Vaulin; Gabriele Vedovato; Salvatore Vitale

2014-05-26T23:59:59.000Z

164

Adaptive filters for detection of gravitational waves from coalescing binaries

In this work we propose use of infinite impulse response adaptive line enhancer (IIR ALE) filters for detection of gravitational waves from coalescing binaries. We extend our previous work and define an adaptive matched filter structure. Filter performance is analyzed in terms of the tracking capability and determination of filter parameters. Furthermore, following the Neyman-Pearson strategy, receiver operating characteristics are derived, with closedform expressions for detection threshold, false alarm, and detection probability. Extensive tests demonstrate the effectiveness of adaptive filters both in terms of small computational cost and robustness.

Eleuteri, Antonio; Milano, Leopoldo; De Rosa, Rosario; Garufi, Fabio; Acernese, Fausto; Barone, Fabrizio; Giordano, Lara; Pardi, Silvio [Dip. di Scienze Fisiche, Universita di Napoli 'Federico II', via Cintia, I-80126 Naples (Italy) and INFN sez. Napoli, via Cintia, I-80126 Naples (Italy); Dip. di Scienze Farmaceutiche, Universita di Salerno, via Ponte Don Melillo, 84084 Fisciano (Saudi Arabia) (IT) and INFN sez. Napoli, via Cintia, I-80126 Naples (Italy); Dip. di Matematica ed Applicazioni, Universita di Napoli 'Federico II', via Cintia, I-80126 Naples (Italy) and INFN sez. Napoli, via Cintia, I-80126 Naples (Italy)

2006-06-15T23:59:59.000Z

165

Relic gravitational waves and the cosmic accelerated expansion

The possibility of reconstructing the whole history of the scale factor of the Universe from the power spectrum of relic gravitational waves (RGWs) makes the study of these waves quite interesting. First, we explore the impact of a hypothetical era -right after reheating- dominated by mini black holes and radiation that may lower the spectrum several orders of magnitude. Next, we calculate the power spectrum of the RGWs taking into account the present stage of accelerated expansion and an hypothetical second dust era. Finally, we study the generalized second law of gravitational thermodynamics applied to the present era of accelerated expansion of the Universe.

German Izquierdo

2006-01-10T23:59:59.000Z

166

Atom interferometric gravitational wave detection using heterodyne laser links

We propose a scheme based on a heterodyne laser link that allows for long baseline gravitational wave detection using atom interferometry. While the baseline length in previous atom-based proposals is constrained by the need for a reference laser to remain collimated as it propagates between two satellites, here we circumvent this requirement by employing a strong local oscillator laser near each atom ensemble that is phase locked to the reference laser beam. Longer baselines offer a number of potential advantages, including enhanced sensitivity, simplified atom optics, and reduced atomic source flux requirements.

Hogan, Jason M

2015-01-01T23:59:59.000Z

167

Gravitational Waves from Periodic Three-Body Systems

Three bodies moving in a periodic orbit under the influence of Newtonian gravity ought to emit gravitational waves. We have calculated the gravitational radiation quadrupolar waveforms and the corresponding luminosities for the 13+11 recently discovered three-body periodic orbits in Newtonian gravity. These waves clearly allow one to distinguish between their sources: all 13+11 orbits have different waveforms and their luminosities (evaluated at the same orbit energy and body mass) vary by up to 13 orders of magnitude in the mean, and up to 20 orders of magnitude for the peak values.

Dmitrašinovi?, V; Hudomal, Ana

2015-01-01T23:59:59.000Z

168

Stochastic background of gravitational waves from cosmological sources

Gravitational waves (GW) can constitute a unique probe of the primordial universe. In many cases, the characteristic frequency of the emitted GW is directly related to the energy scale at which the GW source is operating in the early universe. Consequently, different GW detectors can probe different energy scales in the evolution of the universe. After a general introduction on the properties of a GW stochastic background of primordial origin, some examples of cosmological sources are presented, which may lead to observable GW signals.

Caprini, Chiara

2015-01-01T23:59:59.000Z

169

Black holes and gravitational waves in three-dimensional f(R) gravity

In the three-dimensional pure Einstein gravity, the geometries of the vacuum space-times are always trivial, and gravitational waves (gravitons) are strictly forbidden. For the first time, we find a vacuum circularly symmetric black hole with nontrivial geometries in $f(R)$ gravity theory, in which a true singularity appears. In this frame with nontrivial geometry, a perturbative gravitational wave does exist. Beyond the perturbative level, we make a constructive proof of the existence of a gravitational wave in $f(R)$ gravity, where the Birkhoff-like theorem becomes invalid. We find two classes of exact solutions of circularly symmetric pure gravitational wave radiation and absorption.

Hongsheng Zhang; Dao-Jun Liu; Xin-Zhou Li

2014-12-19T23:59:59.000Z

170

Method for estimation of gravitational-wave transient model parameters in frequency-time maps

A common technique for detection of gravitational-wave signals is searching for excess power in frequency-time maps of gravitational-wave detector data. In the event of a detection, model selection and parameter estimation will be performed in order to explore the properties of the source. In this paper, we develop a Bayesian statistical method for extracting model-dependent parameters from observed gravitational-wave signals in frequency-time maps. We demonstrate the method by recovering the parameters of model gravitational-wave signals added to simulated advanced LIGO noise. We also characterize the performance of the method and discuss prospects for future work.

Michael Coughlin; Nelson Christensen; Jonathan Gair; Shivaraj Kandhasamy; Eric Thrane

2014-04-17T23:59:59.000Z

171

Propagation of gravitational waves in a universe with slowly-changing equation of state

An exact solution for the expansion of a flat universe with dark energy evolving according to a simple model is explored. The equation for weak primordial gravitational waves propagating in this universe is solved and explored; gravitational waves in a flat cosmology possessing both a "big bang" singularity and a "big rip" singularity can be described with confluent Heun functions. We develop approximation methods for confluent Heun equations in regimes of interest to gravitational wave astronomers and predict the diminution in gravitational wave amplitude in a universe with both a Big Bang and a Big Rip.

Edmund Schluessel

2014-06-17T23:59:59.000Z

172

E-Print Network 3.0 - astrophysics gravitational waves Sample...

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

position in astrophysics 3D supercomputer simulation of the formation Summary: , Gamma-ray bursts, nucleosynthesis, sources of gravitational waves and computational methods....

173

Probing strong-field gravity and black holes with gravitational waves

Gravitational wave observations will be excellent tools for making precise measurements of processes that occur in very strong- field regions of space time. Extreme mass

Hughes, Scott A.

174

We report a search for gravitational waves from the inspiral, merger and ringdown of binary black holes (BBH) with total mass between 25 and 100 solar masses, in data taken at the LIGO and Virgo observatories between July 7, 2009 and October 20, 2010. The maximum sensitive distance of the detectors over this period for a (20,20) Msun coalescence was 300 Mpc. No gravitational wave signals were found. We thus report upper limits on the astrophysical coalescence rates of BBH as a function of the component masses for non-spinning components, and also evaluate the dependence of the search sensitivity on component spins aligned with the orbital angular momentum. We find an upper limit at 90% confidence on the coalescence rate of BBH with non-spinning components of mass between 19 and 28 Msun of 3.3 \\times 10^-7 mergers /Mpc^3 /yr.

The LIGO Scientific Collaboration; the Virgo Collaboration; J. Aasi; J. Abadie; B. P. Abbott; R. Abbott; T. D. Abbott; M. Abernathy; T. Accadia; F. Acernese; C. Adams; T. Adams; P. Addesso; R. Adhikari; C. Affeldt; M. Agathos; K. Agatsuma; P. Ajith; B. Allen; A. Allocca; E. Amador Ceron; D. Amariutei; S. B. Anderson; W. G. Anderson; K. Arai; M. C. Araya; S. Ast; S. M. Aston; P. Astone; D. Atkinson; P. Aufmuth; C. Aulbert; B. E. Aylott; S. Babak; P. Baker; G. Ballardin; S. Ballmer; Y. Bao; J. C. B. Barayoga; D. Barker; F. Barone; B. Barr; L. Barsotti; M. Barsuglia; M. A. Barton; I. Bartos; R. Bassiri; M. Bastarrika; A. Basti; J. Batch; J. Bauchrowitz; Th. S. Bauer; M. Bebronne; D. Beck; B. Behnke; M. Bejger; M. G. Beker; A. S. Bell; C. Bell; I. Belopolski; M. Benacquista; J. M. Berliner; A. Bertolini; J. Betzwieser; N. Beveridge; P. T. Beyersdorf; T. Bhadbade; I. A. Bilenko; G. Billingsley; J. Birch; R. Biswas; M. Bitossi; M. A. Bizouard; E. Black; J. K. Blackburn; L. Blackburn; D. Blair; B. Bland; M. Blom; O. Bock; T. P. Bodiya; C. Bogan; C. Bond; R. Bondarescu; F. Bondu; L. Bonelli; R. Bonnand; R. Bork; M. Born; V. Boschi; S. Bose; L. Bosi; B. Bouhou; S. Braccini; C. Bradaschia; P. R. Brady; V. B. Braginsky; M. Branchesi; J. E. Brau; J. Breyer; T. Briant; D. O. Bridges; A. Brillet; M. Brinkmann; V. Brisson; M. Britzger; A. F. Brooks; D. A. Brown; T. Bulik; H. J. Bulten; A. Buonanno; J. Burguet-Castell; D. Buskulic; C. Buy; R. L. Byer; L. Cadonati; G. Cagnoli; E. Calloni; J. B. Camp; P. Campsie; K. Cannon; B. Canuel; J. Cao; C. D. Capano; F. Carbognani; L. Carbone; S. Caride; S. Caudill; M. Cavaglia; F. Cavalier; R. Cavalieri; G. Cella; C. Cepeda; E. Cesarini; T. Chalermsongsak; P. Charlton; E. Chassande-Mottin; W. Chen; X. Chen; Y. Chen; A. Chincarini; A. Chiummo; H. S. Cho; J. Chow; N. Christensen; S. S. Y. Chua; C. T. Y. Chung; S. Chung; G. Ciani; F. Clara; D. E. Clark; J. A. Clark; J. H. Clayton; F. Cleva; E. Coccia; P. -F. Cohadon; C. N. Colacino; A. Colla; M. Colombini; A. Conte; R. Conte; D. Cook; T. R. Corbitt; M. Cordier; N. Cornish; A. Corsi; C. A. Costa; M. Coughlin; J. -P. Coulon; P. Couvares; D. M. Coward; M. Cowart; D. C. Coyne; J. D. E. Creighton; T. D. Creighton; A. M. Cruise; A. Cumming; L. Cunningham; E. Cuoco; R. M. Cutler; K. Dahl; M. Damjanic; S. L. Danilishin; S. D'Antonio; K. Danzmann; V. Dattilo; B. Daudert; H. Daveloza; M. Davier; E. J. Daw; R. Day; T. Dayanga; R. De Rosa; D. DeBra; G. Debreczeni; J. Degallaix; W. Del Pozzo; T. Dent; V. Dergachev; R. DeRosa; S. Dhurandhar; L. Di Fiore; A. Di Lieto; I. Di Palma; M. Di Paolo Emilio; A. Di Virgilio; M. Diaz; A. Dietz; F. Donovan; K. L. Dooley; S. Doravari; S. Dorsher; M. Drago; R. W. P. Drever; J. C. Driggers; Z. Du; J. -C. Dumas; S. Dwyer; T. Eberle; M. Edgar; M. Edwards; A. Effler; P. Ehrens; G. Endroczi; R. Engel; T. Etzel; K. Evans; M. Evans; T. Evans; M. Factourovich; V. Fafone; S. Fairhurst; B. F. Farr; M. Favata; D. Fazi; H. Fehrmann; D. Feldbaum; I. Ferrante; F. Ferrini; F. Fidecaro; L. S. Finn; I. Fiori; R. P. Fisher; R. Flaminio; S. Foley; E. Forsi; L. A. Forte; N. Fotopoulos; J. -D. Fournier; J. Franc; S. Franco; S. Frasca; F. Frasconi; M. Frede; M. A. Frei; Z. Frei; A. Freise; R. Frey; T. T. Fricke; D. Friedrich; P. Fritschel; V. V. Frolov; M. -K. Fujimoto; P. J. Fulda; M. Fyffe; J. Gair; M. Galimberti; L. Gammaitoni; J. Garcia; F. Garufi; M. E. Gaspar; G. Gelencser; G. Gemme; E. Genin; A. Gennai; L. A. Gergely; S. Ghosh; J. A. Giaime; S. Giampanis; K. D. Giardina; A. Giazotto; S. Gil-Casanova; C. Gill; J. Gleason; E. Goetz; G. Gonzalez; M. L. Gorodetsky; S. Gossler; R. Gouaty; C. Graef; P. B. Graff; M. Granata; A. Grant; C. Gray; R. J. S. Greenhalgh; A. M. Gretarsson; C. Griffo; H. Grote; K. Grover; S. Grunewald; G. M. Guidi; C. Guido; R. Gupta; E. K. Gustafson; R. Gustafson; J. M. Hallam; D. Hammer; G. Hammond; J. Hanks; C. Hanna; J. Hanson; J. Harms; G. M. Harry; I. W. Harry; E. D. Harstad; M. T. Hartman; K. Haughian; K. Hayama; J. -F. Hayau; J. Heefner; A. Heidmann; M. C. Heintze; H. Heitmann; P. Hello; G. Hemming; M. A. Hendry; I. S. Heng; A. W. Heptonstall; V. Herrera; M. Heurs; M. Hewitson; S. Hild; D. Hoak; K. A. Hodge; K. Holt; M. Holtrop; T. Hong; S. Hooper; J. Hough; E. J. Howell; B. Hughey; S. Husa; S. H. Huttner; T. Huynh-Dinh; D. R. Ingram; R. Inta; T. Isogai; A. Ivanov; K. Izumi; M. Jacobson; E. James; Y. J. Jang; P. Jaranowski; E. Jesse; W. W. Johnson; D. I. Jones; R. Jones; R. J. G. Jonker; L. Ju; P. Kalmus; V. Kalogera; S. Kandhasamy; G. Kang; J. B. Kanner; M. Kasprzack; R. Kasturi; E. Katsavounidis; W. Katzman; H. Kaufer; K. Kaufman; K. Kawabe; S. Kawamura; F. Kawazoe; D. Keitel; D. Kelley; W. Kells; D. G. Keppel; Z. Keresztes; A. Khalaidovski; F. Y. Khalili; E. A. Khazanov; B. K. Kim; C. Kim; H. Kim; K. Kim; N. Kim; Y. M. Kim; P. J. King; D. L. Kinzel; J. S. Kissel; S. Klimenko

2013-02-25T23:59:59.000Z

175

In space laser interferometer gravitational wave (G.W.) detection missions, the stability of the laser beam pointing direction has to be kept at 10 nrad/?Hz. Otherwise, the beam pointing jitter noise will dominate the noise budget and make the detection of G.W. impossible. Disturbed by the residue non-conservative forces, the fluctuation of the laser beam pointing direction could be a few ?rad/?Hz at frequencies from 0.1 mHz to 10 Hz. Therefore, the laser beam pointing control system is an essential requirement for those space G.W. detection missions. An on-ground test of such beam pointing control system is performed, where the Differential Wave-front Sensing technique is used to sense the beams pointing jitter. An active controlled steering mirror is employed to adjust the beam pointing direction to compensate the jitter. The experimental result shows that the pointing control system can be used for very large dynamic range up to 5 ?rad. At the interested frequencies of space G.W. detection missions, between 1 mHz and 1 Hz, beam pointing stability of 6 nrad/?Hz is achieved.

Dong, Yu-Hui; Liu, He-Shan [National Microgravity Laboratory (NML), Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190 (China); University of Chinese Academy of Sciences, Beijing 100190 (China); Luo, Zi-Ren; Li, Yu-Qiong; Jin, Gang, E-mail: gajin@imech.ac.cn [National Microgravity Laboratory (NML), Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190 (China)

2014-07-15T23:59:59.000Z

176

Short Gamma-Ray Bursts and Gravitational Waves from Dynamically Formed Merging Binaries

Merging binary systems consisting of two collapsed objects are among the most promising sources of high frequency gravitational wave, GW, signals for ground based interferometers. Double neutron star or black hole/neutron star mergers are also believed to give rise to short hard bursts, SHBs, a subclass of gamma ray bursts. SHBs might thus provide a powerful way to infer the merger rate of two-collapsed object binaries. Under the hypothesis that most SHBs originate from double neutron star or black hole/neutron star mergers, we outline here a method to estimate the incidence of merging events from dynamically formed binaries in globular clusters and infer the corresponding GW event rate that can be detected with Advanced LIGO/Virgo. In particular a sizeable fraction of detectable GW events is expected to be coincident with SHBs. The beaming and redshift distribution of SHBs are reassessed and their luminosity function constrained by using the results from recent SHBs observations. We confirm that a substantial fraction of SHBs goes off at low redshifts, where the merging of systems formed in globular clusters through dynamical interactions is expected.

Dafne Guetta; Luigi Stella

2008-11-10T23:59:59.000Z

177

All-sky search for periodic gravitational waves in LIGO S4 data

We report on an all-sky search with the LIGO detectors for periodic gravitational waves in the frequency range 50-1000 Hz and with the frequency's time derivative in the range -1.0E-8 Hz/s to zero. Data from the fourth LIGO science run (S4) have been used in this search. Three different semi-coherent methods of transforming and summing strain power from Short Fourier Transforms (SFTs) of the calibrated data have been used. The first, known as "StackSlide", averages normalized power from each SFT. A "weighted Hough" scheme is also developed and used, and which also allows for a multi-interferometer search. The third method, known as "PowerFlux", is a variant of the StackSlide method in which the power is weighted before summing. In both the weighted Hough and PowerFlux methods, the weights are chosen according to the noise and detector antenna-pattern to maximize the signal-to-noise ratio. The respective advantages and disadvantages of these methods are discussed. Observing no evidence of periodic gravitationa...

Abbott, B; Adhikari, R; Agresti, J; Ajith, P; Allen, B; Amin, R; Anderson, S B; Anderson, W G; Arain, M; Araya, M; Armandula, H; Ashley, M; Aston, S; Aufmuth, P; Aulbert, C; Babak, S; Ballmer, S; Bantilan, H; Barish, B C; Barker, C; Barker, D; Barr, B; Barriga, P; Barton, M A; Bayer, K; Belczynski, K; Betzwieser, J; Beyersdorf, P T; Bhawal, B; Bilenko, I A; Billingsley, G; Biswas, R; Black, E; Blackburn, K; Blackburn, L; Blair, D; Bland, B; Bogenstahl, J; Bogue, L; Bork, R; Boschi, V; Bose, S; Brady, P R; Braginsky, V B; Brau, J E; Brinkmann, M; Brooks, A; Brown, D A; Bullington, A; Bunkowski, A; Buonanno, A; Burmeister, O; Busby, D; Byer, R L; Cadonati, L; Cagnoli, G; Camp, J B; Cannizzo, J; Cannon, K; Cantley, C A; Cao, J; Cardenas, L; Casey, M M; Castaldi, G; Cepeda, C; Chalkey, E; Charlton, P; Chatterji, S; Chelkowski, S; Chen, Y; Chiadini, F; Chin, D; Chin, E; Chow, J; Christensen, N; Clark, J; Cochrane, P; Cokelaer, T; Colacino, C N; Coldwell, R; Conte, R; Cook, D; Corbitt, T; Coward, D; Coyne, D; Creighton, J D E; Creighton, T D; Croce, R P; Crooks, D R M; Cruise, A M; Cumming, A; Dalrymple, J; D'Ambrosio, E; Danzmann, K; Davies, G; De Bra, D; Degallaix, J; Degree, M; Demma, T; Dergachev, V; Desai, S; DeSalvo, R; Dhurandhar, S; Daz, M; Dickson, J; Di Credico, A; Diederichs, G; Dietz, A; Doomes, E E; Drever, R W P; Dumas, J C; Dupuis, R J; Dwyer, J G; Ehrens, P; Espinoza, E; Etzel, T; Evans, M; Evans, T; Fairhurst, S; Fan, Y; Fazi, D; Fejer, M M; Finn, L S; Fiumara, V; Fotopoulos, N; Franzen, A; Franzen, K Y; Freise, A; Frey, R; Fricke, T; Fritschel, P; Frolov, V V; Fyffe, M; Galdi, V; Garofoli, J; Gholami, I; Giaime, J A; Giampanis, S; Giardina, K D; Goda, K; Goetz, E; Goggin, L M; González, G; Gossler, S; Grant, A; Gras, S; Gray, a C; Gray, M; Greenhalgh, J; Gretarsson, A M; Grosso, R; Grote, H; Grünewald, S; Günther, M; Gustafson, R; Hage, B; Hammer, D; Hanna, C; Hanson, J; Harms, J; Harry, G; Harstad, E; Hayler, T; Heefner, J; Heng, I S; Heptonstall, A; Heurs, M; Hewitson, M; Hild, S; Hirose, E; Hoak, D; Hosken, D; Hough, J; Howell, E; Hoyland, D; Huttner, S H; Ingram, D; Innerhofer, E; Ito, M; Itoh, Y; Ivanov, A; Jackrel, D; Johnson, B; Johnson, W W; Jones, D I; Jones, G; Jones, R; Ju, L; Kalmus, Peter Ignaz Paul; Kalogera, V; Kasprzyk, D; Katsavounidis, E; Kawabe, K; Kawamura, S; Kawazoe, F; Kells, W; Keppel, D G; Khalili, F Ya; Kim, C; King, P; Kissel, J S; Klimenko, S; Kokeyama, K; Kondrashov, V; Kopparapu, R K; Kozak, D; Krishnan, B; Kwee, P; Lam, P K; Landry, M; Lantz, B; Lazzarini, A; Lee, B; Lei, M; Leiner, J; Leonhardt, V; Leonor, I; Libbrecht, K; Lindquist, P; Lockerbie, N A; Longo, M; Lormand, M; Lubinski, M; Luck, H; Machenschalk, B; MacInnis, M; Mageswaran, M; Mailand, K; Malec, M; Mandic, V; Marano, S; Marka, S; Markowitz, J; Maros, E; Martin, I; Marx, J N; Mason, K; Matone, L; Matta, V; Mavalvala, a N; McCarthy, R; McClelland, D E; McGuire, S C; McHugh, M; McKenzie, K; McNabb, J W C; McWilliams, S; Meier, T; Melissinos, A; Mendell, G; Mercer, R A; Meshkov, S; Messaritaki, E; Messenger, C J; Meyers, D; Mikhailov, E; Mitra, S; Mitrofanov, V P; Mitselmakher, G; Mittleman, R; Miyakawa, O; Mohanty, S; Moreno, G; Mossavi, K; Mow Lowry, C; Moylan, A; Mudge, D; Müller, G; Mukherjee, S; Muller-Ebhardt, H; Munch, J; Murray, P; Myers, E; Myers, J; Nash, T; Newton, G; Nishizawa, A; Numata, K; O'Reilly, B; O'Shaughnessy, R; Ottaway, D J; Overmier, H; Owen, B J; Pan, Y; Papa, M A; Parameshwaraiah, V; Patel, P; Pedraza, M; Penn, S; Pierro, V; Pinto, I M; Pitkin, M; Pletsch, H; Plissi, M V; Postiglione, F; Prix, R; Quetschke, V; Raab, F; Rabeling, D; Radkins, H; Rahkola, R; Rainer, N; Rakhmanov, M; Ramsunder, M; Rawlins, K; Ray-Majumder, S; Re, V; Rehbein, H; Reid, S; Reitze, D H; Ribichini, L; Riesen, R; Riles, K; Rivera, B; Robertson, N A; Robinson, C; Robinson, E L; Roddy, S; Rodríguez, A; Rogan, A M; Rollins, J; Romano, J D; Romie, J; Route, R; Rowan, S; Rüdiger, A; Ruet, L; Russell, P; Ryan, K; Sakata, S; Samidi, M; Sancho de la Jordana, L; Sandberg, V; Sannibale, V; Saraf, S; Sarin, P; Sathyaprakash, B S; Sato, S; Saulson, P R; Savage, R; Savov, P; Schediwy, S; Schilling, R; Schnabel, R; Schofield, R; Schutz, B F; Schwinberg, P; Scott, S M; Searle, A C; Sears, B; Seifert, F; Sellers, D; Sengupta, A S; Shawhan, P; Shoemaker, D H; Sibley, A; Sidles, J A; Siemens, X; Sigg, D; Sinha, S; Sintes, A M; Slagmolen, B J J; Slutsky, J; Smith, J R; Smith, M R; Somiya, K; Strain, K A; Strom, D M; Stuver, A; Summerscales, T Z; Sun, K X; Sung, M; Sutton, P J; Takahashi, H; Tanner, D B; Tarallo, M; Taylor, R; Taylor, R; Thacker, J; Thorne, K A; Thorne, K S; Thüring, A; Tokmakov, K V; Torres, C; Torrie, C; Traylor, G; Trias, M; Tyler, W; Ugolini, D; Ungarelli, C; Urbanek, K; Vahlbruch, H; Vallisneri, M; Van Den Broeck, C; Varvella, M; Vass, S; Vecchio, A; Veitch, J; Veitch, P; Villar, A; Vorvick, C

2007-01-01T23:59:59.000Z

178

Strong gravitational lensing of gravitational waves in Einstein Telescope

Gravitational wave experiments have entered a new stage which gets us closer to the opening a new observational window on the Universe. In particular, the Einstein Telescope (ET) is designed to have a fantastic sensitivity that will provide with tens or hundreds of thousand NS-NS inspiral events per year up to the redshift z = 2. Some of such events should be gravitationally lensed by intervening galaxies. We explore the prospects of observing gravitationally lensed inspiral NS-NS events in the Einstein telescope. Being conservative we consider the lens population of elliptical galaxies. It turns out that depending on the local insipral rate ET should detect from one per decade detection in the pessimistic case to a tens of detections per year for the most optimistic case. The detection of gravitationally lensed source in gravitational wave detectors would be an invaluable source of information concerning cosmography, complementary to standard ones (like supernovae or BAO) independent of the local cosmic distance ladder calibrations.

Piórkowska, Aleksandra; Biesiada, Marek [Department of Astrophysics and Cosmology, Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice (Poland); Zhu, Zong-Hong, E-mail: aleksandra.piorkowska@us.edu.pl, E-mail: marek.biesiada@us.edu.pl, E-mail: zhuzh@bnu.edu.cn [Department of Astronomy, Beijing Normal University, Beijing 100875 (China)

2013-10-01T23:59:59.000Z

179

Accelerated gravitational-wave parameter estimation with reduced order modeling

Inferring the astrophysical parameters of coalescing compact binaries is a key science goal of the upcoming advanced LIGO-Virgo gravitational-wave detector network and, more generally, gravitational-wave astronomy. However, current parameter estimation approaches for such scenarios can lead to computationally intractable problems in practice. Therefore there is a pressing need for new, fast and accurate Bayesian inference techniques. In this letter we demonstrate that a reduced order modeling approach enables rapid parameter estimation studies. By implementing a reduced order quadrature scheme within the LIGO Algorithm Library, we show that Bayesian inference on the 9-dimensional parameter space of non-spinning binary neutron star inspirals can be sped up by a factor of 30 for the early advanced detectors' configurations. This speed-up will increase to about $150$ as the detectors improve their low-frequency limit to 10Hz, reducing to hours analyses which would otherwise take months to complete. Although these results focus on gravitational detectors, the techniques are broadly applicable to any experiment where fast Bayesian analysis is desirable.

Priscilla Canizares; Scott E. Field; Jonathan Gair; Vivien Raymond; Rory Smith; Manuel Tiglio

2015-01-27T23:59:59.000Z

180

Detectability of Inflationary Gravitational Waves with Microwave Background Polarization

Inflation predicts specific relations between the amplitudes and spectral indices of the primordial spectrum of density (scalar metric) perturbations and gravitational waves (tensor metric perturbations). Detection of a stochastic gravitational-wave background is essential for identifying this unmistakable signature. Polarization of the cosmic microwave background can isolate these tensor modes in a model-independent way and thereby circumvent the cosmic-variance limit to detecting a small tensor signal with only a temperature map. Here we assess the detectability of a gravity-wave background with a temperature and polarization map. For detector sensitivities better than $10-20 \\mu K \\sqrt{sec}$, the sensitivity to a tensor signal is always dominated by the polarization map. With a detector sensitivity of order $1 \\mu K \\sqrt{sec}$, polarization could improve on a temperature-map sensitivity to tensor modes by two to three orders of magnitude. Even a small amount of reionization substantially enhances tensor-mode detectability. We also argue that the sensitivity of the Planck Surveyor to tensor modes is significantly improved with polarization, even taking into account the resulting degradation of the intensity determination in the high-frequency channels.

Marc Kamionkowski; Arthur Kosowsky

1997-05-28T23:59:59.000Z

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181

Laser-Ranging Long Baseline Differential Atom Interferometers for Space

High sensitivity differential atom interferometers are promising for precision measurements in science frontiers in space, including gravity field mapping for Earth science studies and gravitational wave detection. We propose a new configuration of twin atom interferometers connected by a laser ranging interferometer (LRI-AI) to provide precise information of the displacements between the two AI reference mirrors and a means to phase-lock the two independent interferometer lasers over long distances, thereby further enhancing the feasibility of long baseline differential atom interferometers. We show that a properly implemented LRI-AI can achieve equivalent functionality to the conventional differential atom interferometer measurement system. LRI-AI isolates the laser requirements for atom interferometers and for optical phase readout between distant locations, thus enabling optimized allocation of available laser power within a limited physical size and resource budget. A unique aspect of LRI-AI also enables...

Chiow, Sheng-wey; Yu, Nan

2015-01-01T23:59:59.000Z

182

The general theory of time-dependent frequency and time-dependent mass ('effective mass') is described.The general theory for time-dependent harmonic- oscillator is applied in the present research for studying certain quantum effects in the interferometers for detecting gravitational waves.When an astronomical binary system approaches its point of coalescence the gravitational wave intensity and frequency are increasing and this can lead to strong deviations from the simple description of harmonic-oscillations for the interferometric masses on which the mirrors are placed.It is shown that under such condtions the harmonic-oscillations of these masses can be described by mechanical harmonic-oscillators with time-dependent frequency and effective-mass. In the present theoretical model the effective-mass is decreasing with time describing pumping phenomena in which the oscillator amplitude is increasing with time . The quantization of this system is analyzed by the use of the adiabatic approximation. It is found that the increase of the gravitational wave intensity, within the adiabatic approximation, leads to squeezing phenomena where the quantum noise in one quadrature is increased and in the other quadrature is decreased.

Yacob Ben-Aryeh

2008-07-29T23:59:59.000Z

183

We carry out two searches for periodic gravitational waves using the most sensitive few hours of data from the second LIGO science run. The first search is targeted at isolated, previously unknown neutron stars and covers the entire sky in the frequency band 160-728.8 Hz. The second search targets the accreting neutron star in the low-mass X-ray binary Scorpius X-1, covers the frequency bands 464-484 Hz and 604-624 Hz, and two binary orbit parameters. Both searches look for coincidences between the Livingston and Hanford 4-km interferometers. For isolated neutron stars our 95% confidence upper limits on the gravitational wave strain amplitude range from 6.6E-23 to 1E-21 across the frequency band; For Scorpius X-1 they range from 1.7E-22 to 1.3E-21 across the two 20-Hz frequency bands. The upper limits presented in this paper are the first broad-band wide parameter space upper limits on periodic gravitational waves using coherent search techniques. The methods developed here lay the foundations for upcoming hi...

Abbott, B; Adhikari, R; Ageev, A; Agresti, J; Allen, B; Allen, J; Amin, R; Anderson, S B; Anderson, W G; Araya, M; Armandula, H; Ashley, M; Asiri, F; Aufmuth, P; Aulbert, C; Babak, S; Balasubramanian, R; Ballmer, S; Barish, B C; Barker, C; Barker, D; Barnes, M; Barr, B; Barton, M A; Bayer, K; Beausoleil, R; Belczynski, K; Bennett, R; Berukoff, S J; Betzwieser, J; Bhawal, B; Bilenko, I A; Billingsley, G; Black, E; Blackburn, K; Blackburn, L; Bland, B; Bochner, B; Bogue, L; Bork, R; Bose, S; Brady, P R; Braginsky, V B; Brau, J E; Brown, D A; Bullington, A; Bunkowski, A; Buonanno, A; Burgess, R; Busby, D; Butler, W E; Byer, R L; Cadonati, L; Cagnoli, G; Camp, J B; Cannizzo, J; Cannon, K; Cantley, C A; Cardenas, L; Carter, K; Casey, M M; Castiglione, J; Chandler, A; Chapsky, J; Charlton, P; Chatterji, S; Chelkowski, S; Chen, Y; Chickarmane, V; Chin, D; Christensen, N; Churches, D; Cokelaer, T; Colacino, C; Coldwell, R; Coles, M; Cook, D; Corbitt, T; Coyne, D; Creighton, J D E; Creighton, T D; Crooks, D R M; Csatorday, P; Cusack, B J; Cutler, C; Dalrymple, J; D'Ambrosio, E; Danzmann, K; Davies, G; Daw, E; De Bra, D; Delker, T; Dergachev, V; Desai, S; DeSalvo, R; Dhurandhar, S V; Di Credico, A; Ding, H; Drever, R W P; Dupuis, R J; Edlund, J A; Ehrens, P; Elliffe, E J; Etzel, T; Evans, M; Evans, T; Fairhurst, S; Fallnich, C; Farnham, D; Fejer, M M; Findley, T; Fine, M; Finn, L S; Franzen, K Y; Freise, A; Frey, R; Fritschel, P; Frolov, V V; Fyffe, M; Ganezer, K S; Garofoli, J; Giaime, J A; Gillespie, A; Goda, K; Goggin, L; González, G; Gossler, S; Grandclément, P; Grant, A; Gray, C; Gretarsson, A M; Grimmett, D; Grote, H; Grünewald, S; Günther, M; Gustafson, E; Gustafson, R; Hamilton, W O; Hammond, M; Hanson, J; Hardham, C; Harms, J; Harry, G; Hartunian, A; Heefner, J; Hefetz, Y; Heinzel, G; Heng, I S; Hennessy, M; Hepler, N; Heptonstall, A; Heurs, M; Hewitson, M; Hild, S; Hindman, N; Hoang, P; Hough, J; Hrynevych, M; Hua, W; Ito, M; Itoh, Y; Ivanov, A; Jennrich, O; Johnson, B; Johnson, W W; Johnston, W R; Jones, D I; Jones, G; Jones, L; Jungwirth, D; Kalogera, V; Katsavounidis, E; Kawabe, K; Kawamura, S; Kells, W; Kern, J; Khan, A; Killbourn, S; Killow, C J; Kim, C; King, C; King, P; Klimenko, S; Koranda, S; Kotter, K; Kovalik, Yu; Kozak, D; Krishnan, B; Landry, M; Langdale, J; Lantz, B; Lawrence, R; Lazzarini, A; Lei, M; Leonor, I; Libbrecht, K; Libson, A; Lindquist, P; Liu, S; Logan, J; Lormand, M; Lubinski, M; Luck, H; Luna, M; Lyons, T T; Machenschalk, B; MacInnis, M; Mageswaran, M; Mailand, K; Majid, W; Malec, M; Mandic, V; Mann, F; Marin, A; Marka, S; Maros, E; Mason, J; Mason, K; Matherny, O; Matone, L; Mavalvala, N; McCarthy, R; McClelland, D E; McHugh, M; McNabb, J W C; Melissinos, A C; Mendell, G; Mercer, R A; Meshkov, S; Messaritaki, E; Messenger, C; Mikhailov, E; Mitra, S; Mitrofanov, V P; Mitselmakher, G; Mittleman, R; Miyakawa, O; Miyoki, S; Mohanty, S; Moreno, G; Mossavi, K; Müller, G; Mukherjee, S; Murray, P; Myers, E; Myers, J; Nagano, S; Nash, T; Nayak, R; Newton, G; Nocera, F; Noel, J S; Nutzman, P; Olson, T; O'Reilly, B; Ottaway, D J; Ottewill, A; Ouimette, D A; Overmier, H; Owen, B J; Pan, Y; Papa, M A; Parameshwaraiah, V; Parameswaran, A J; Parameswariah, C; Pedraza, M; Penn, S; Pitkin, M; Plissi, M; Prix, R; Quetschke, V; Raab, F; Radkins, H; Rahkola, R; Rakhmanov, M; Rao, S R; Rawlins, K; Ray-Majumder, S; Re, V; Redding, D; Regehr, M W; Regimbau, T; Reid, S; Reilly, K T; Reithmaier, K; Reitze, D H; Richman, S; Riesen, R; Riles, K; Rivera, B; Rizzi, A; Robertson, D I; Robertson, N A; Robinson, C; Robison, L; Roddy, S; Rodríguez, A; Rollins, J; Romano, J D; Romie, J; Rong, H; Rose, D; Rotthoff, E; Rowan, S; Rüdiger, A; Ruet, L; Russell, P; Ryan, K; Salzman, I; Sanchodela, L; Jordana; Sandberg, V; Sanders, G H; Sannibale, V; Sarin, P; Sathyaprakash, B; Saulson, P R; Savage, R; Sazonov, A; Schilling, R; Schlaufman, K; Schmidt, V; Schnabel, R; Schofield, R; Schutz, B F; Schwinberg, P; Scott, S M; Seader, S E; Searle, A C; Sears, B; Seel, S; Seifert, F; Sellers, D; Sengupta, A S; Shapiro, C A; Shawhan, P; Shoemaker, D H; Shu, Q Z; Sibley, A; Siemens, X; Sievers, L; Sigg, D; Sintes, A M; Smith, J R; Smith, M; Smith, M R; Sneddon, P H; Spero, R; Spjeld, O; Stapfer, G; Steussy, D; Strain, K A; Strom, D; Stuver, A; Summerscales, T; Sumner, M C; Sung, M; Sutton, P J; Sylvestre, J; Takamori, A; Tanner, D B; Tariq, H; Taylor, I; Taylor, R; Taylor, R; Thorne, K A; Thorne, K S; Tibbits, M; Tilav, S; Tinto, M; Tokmakov, 2K V; Torres, C; Torrie, C; Traylor, G; Tyler, W; Ugolini, D W; Ungarelli, C; Vallisneri, M; Van Putten, M H P M; Vass, S; Vecchio, A; Veitch, J; Vorvick, C; Vyachanin, S P; Wallace, L; Walther, H; Ward, H; Ward, R; Ware, B; Watts, K; Webber, D; Weidner, A; Weiland, U; Weinstein, A; Weiss, R; Welling, H; Wen, L; Wen, S; Wette, K; Whelan, J T; Whitcomb, S E; Whiting, B F; Wiley, S

2006-01-01T23:59:59.000Z

184

astroph/9610086 Quasar Proper Motions and LowFrequency Gravitational Waves

astroÂph/9610086 11 Oct 1996 Quasar Proper Motions and LowÂFrequency Gravitational Waves Carl R observational upper limits on the massÂenergy of the cosmological gravitationalÂwave background, from limits on proper motions of quasars. Gravitational waves with periods longer than the time span of observations

Fygenson, Deborah Kuchnir

185

Electromagnetic waves and Stokes parameters in the wake of a gravitational wave

A theoretical description of electromagnetic waves in the background of a (weak) gravitational wave is presented. Explicit expressions are obtained for the Stokes parameters during the passage of a plane-fronted gravitational wave described by the Ehlers-Kundt metric. In particular, it is shown that the axis of the polarization ellipse oscillates, its ellipticity remaining constant.

Shahen Hacyan

2012-06-15T23:59:59.000Z

186

by the plasma from the GW and in the kind of plasma waves excited by the GW, and we focus on the case of veryInteraction of gravitational waves with strongly magnetized plasmas Heinz Isliker,1,* Ingmar of a gravitational wave (GW) with a plasma that is strongly magnetized. The GW is considered a small disturbance

Isliker, Heinz

187

On the energy transported by exact plane gravitational-wave solutions

The energy and momentum transported by exact plane gravitational-wave solutions of Einstein equations are computed using the teleparallel equivalent formulation of Einstein's theory. It is shown that these waves transport neither energy nor momentum. A comparison with the usual linear plane gravitational-waves solution of the linearized Einstein equation is presented.

Yuri N. Obukhov; J. G. Pereira; Guillermo F. Rubilar

2009-09-24T23:59:59.000Z

188

Improved methods for detecting gravitational waves associated with short gamma-ray bursts

In the era of second generation ground-based gravitational wave detectors, short gamma-ray bursts (GRBs) will be among the most promising astrophysical events for joint electromagnetic and gravitational wave observation. A targeted search for gravitational wave compact binary merger signals in coincidence with short GRBs was developed and used to analyze data from the first generation LIGO and Virgo instruments. In this paper, we present improvements to this search that enhance our ability to detect gravitational wave counterparts to short GRBs. Specifically, we introduce an improved method for estimating the gravitational wave background to obtain the event significance required to make detections; implement a method of tiling extended sky regions, as required when searching for signals associated to poorly localized GRBs from Fermi Gamma-ray Burst Monitor or the InterPlanetary Network; and incorporate astrophysical knowledge about the beaming of GRB emission to restrict the search parameter space. We descri...

Williamson, A R; Fairhurst, S; Harry, I W; Macdonald, E; Macleod, D; Predoi, V

2014-01-01T23:59:59.000Z

189

We report on a search for gravitational waves from coalescing compact binaries, of total mass between 2 and 35M[subscript ?], using LIGO observations between November 14, 2006 and May 18, 2007. No gravitational-wave signals ...

Zucker, Michael E.

190

Search for Gravitational Waves from Intermediate Mass Binary Black Holes

We present the results of a weakly modeled burst search for gravitational waves from mergers of non-spinning intermediate mass black holes (IMBH) in the total mass range 100--450 solar masses and with the component mass ratios between 1:1 and 4:1. The search was conducted on data collected by the LIGO and Virgo detectors between November of 2005 and October of 2007. No plausible signals were observed by the search which constrains the astrophysical rates of the IMBH mergers as a function of the component masses. In the most efficiently detected bin centered on 88+88 solar masses, for non-spinning sources, the rate density upper limit is 0.13 per Mpc^3 per Myr at the 90% confidence level.

the LIGO Scientific Collaboration; the Virgo Collaboration; J. Abadie; B. P. Abbott; R. Abbott; T. D. Abbott; M. Abernathy; T. Accadia; F. Acernese; C. Adams; R. Adhikari; C. Affeldt; M. Agathos; K. Agatsuma; P. Ajith; B. Allen; E. Amador Ceron; D. Amariutei; S. B. Anderson; W. G. Anderson; K. Arai; M. A. Arain; M. C. Araya; S. M. Aston; P. Astone; D. Atkinson; P. Aufmuth; C. Aulbert; B. E. Aylott; S. Babak; P. Baker; G. Ballardin; S. Ballmer; J. C. B. Barayoga; D. Barker; F. Barone; B. Barr; L. Barsotti; M. Barsuglia; M. A. Barton; I. Bartos; R. Bassiri; M. Bastarrika; A. Basti; J. Batch; J. Bauchrowitz; Th. S. Bauer; M. Bebronne; D. Beck; B. Behnke; M. Bejger; M. G. Beker; A. S. Bell; A. Belletoile; I. Belopolski; M. Benacquista; J. M. Berliner; A. Bertolini; J. Betzwieser; N. Beveridge; P. T. Beyersdorf; I. A. Bilenko; G. Billingsley; J. Birch; R. Biswas; M. Bitossi; M. A. Bizouard; E. Black; J. K. Blackburn; L. Blackburn; D. Blair; B. Bland; M. Blom; O. Bock; T. P. Bodiya; C. Bogan; R. Bondarescu; F. Bondu; L. Bonelli; R. Bonnand; R. Bork; M. Born; V. Boschi; S. Bose; L. Bosi; B. Bouhou; S. Braccini; C. Bradaschia; P. R. Brady; V. B. Braginsky; M. Branchesi; J. E. Brau; J. Breyer; T. Briant; D. O. Bridges; A. Brillet; M. Brinkmann; V. Brisson; M. Britzger; A. F. Brooks; D. A. Brown; T. Bulik; H. J. Bulten; A. Buonanno; J. Burguet-Castell; D. Buskulic; C. Buy; R. L. Byer; L. Cadonati; G. Cagnoli; E. Calloni; J. B. Camp; P. Campsie; J. Cannizzo; K. Cannon; B. Canuel; J. Cao; C. D. Capano; F. Carbognani; L. Carbone; S. Caride; S. Caudill; M. Cavaglia; F. Cavalier; R. Cavalieri; G. Cella; C. Cepeda; E. Cesarini; O. Chaibi; T. Chalermsongsak; P. Charlton; E. Chassande-Mottin; S. Chelkowski; W. Chen; X. Chen; Y. Chen; A. Chincarini; A. Chiummo; H. Cho; J. Chow; N. Christensen; S. S. Y. Chua; C. T. Y. Chung; S. Chung; G. Ciani; F. Clara; D. E. Clark; J. Clark; J. H. Clayton; F. Cleva; E. Coccia; P. -F. Cohadon; C. N. Colacino; J. Colas; A. Colla; M. Colombini; A. Conte; R. Conte; D. Cook; T. R. Corbitt; M. Cordier; N. Cornish; A. Corsi; C. A. Costa; M. Coughlin; J. -P. Coulon; P. Couvares; D. M. Coward; M. Cowart; D. C. Coyne; J. D. E. Creighton; T. D. Creighton; A. M. Cruise; A. Cumming; L. Cunningham; E. Cuoco; R. M. Cutler; K. Dahl; S. L. Danilishin; R. Dannenberg; S. D'Antonio; K. Danzmann; V. Dattilo; B. Daudert; H. Daveloza; M. Davier; E. J. Daw; R. Day; T. Dayanga; R. De Rosa; D. DeBra; G. Debreczeni; W. Del Pozzo; M. del Prete; T. Dent; V. Dergachev; R. DeRosa; R. DeSalvo; S. Dhurandhar; L. Di Fiore; A. Di Lieto; I. Di Palma; M. Di Paolo Emilio; A. Di Virgilio; M. Diaz; A. Dietz; F. Donovan; K. L. Dooley; M. Drago; R. W. P. Drever; J. C. Driggers; Z. Du; J. -C. Dumas; S. Dwyer; T. Eberle; M. Edgar; M. Edwards; A. Effler; P. Ehrens; G. Endroczi; R. Engel; T. Etzel; K. Evans; M. Evans; T. Evans; M. Factourovich; V. Fafone; S. Fairhurst; Y. Fan; B. F. Farr; D. Fazi; H. Fehrmann; D. Feldbaum; F. Feroz; I. Ferrante; F. Fidecaro; L. S. Finn; I. Fiori; R. P. Fisher; R. Flaminio; M. Flanigan; S. Foley; E. Forsi; L. A. Forte; N. Fotopoulos; J. -D. Fournier; J. Franc; S. Frasca; F. Frasconi; M. Frede; M. Frei; Z. Frei; A. Freise; R. Frey; T. T. Fricke; D. Friedrich; P. Fritschel; V. V. Frolov; M. -K. Fujimoto; P. J. Fulda; M. Fyffe; J. Gair; M. Galimberti; L. Gammaitoni; J. Garcia; F. Garufi; M. E. Gaspar; G. Gemme; R. Geng; E. Genin; A. Gennai; L. A. Gergely; S. Ghosh; J. A. Giaime; S. Giampanis; K. D. Giardina; A. Giazotto; S. Gil; C. Gill; J. Gleason; E. Goetz; L. M. Goggin; G. Gonzalez; M. L. Gorodetsky; S. Gossler; R. Gouaty; C. Graef; P. B. Graff; M. Granata; A. Grant; S. Gras; C. Gray; N. Gray; R. J. S. Greenhalgh; A. M. Gretarsson; C. Greverie; R. Grosso; H. Grote; S. Grunewald; G. M. Guidi; C. Guido; R. Gupta; E. K. Gustafson; R. Gustafson; T. Ha; J. M. Hallam; D. Hammer; G. Hammond; J. Hanks; C. Hanna; J. Hanson; J. Harms; G. M. Harry; I. W. Harry; E. D. Harstad; M. T. Hartman; K. Haughian; K. Hayama; J. -F. Hayau; J. Heefner; A. Heidmann; M. C. Heintze; H. Heitmann; P. Hello; M. A. Hendry; I. S. Heng; A. W. Heptonstall; V. Herrera; M. Hewitson; S. Hild; D. Hoak; K. A. Hodge; K. Holt; M. Holtrop; T. Hong; S. Hooper; D. J. Hosken; J. Hough; E. J. Howell; B. Hughey; S. Husa; S. H. Huttner; T. Huynh-Dinh; D. R. Ingram; R. Inta; T. Isogai; A. Ivanov; K. Izumi; M. Jacobson; E. James; Y. J. Jang; P. Jaranowski; E. Jesse; W. W. Johnson; D. I. Jones; G. Jones; R. Jones; L. Ju; P. Kalmus; V. Kalogera; S. Kandhasamy; G. Kang; J. B. Kanner; R. Kasturi; E. Katsavounidis; W. Katzman; H. Kaufer; K. Kawabe; S. Kawamura; F. Kawazoe; D. Kelley; W. Kells; D. G. Keppel; Z. Keresztes; A. Khalaidovski; F. Y. Khalili; E. A. Khazanov; B. Kim; C. Kim; H. Kim; K. Kim; N. Kim; Y. -M. Kim; P. J. King; D. L. Kinzel; J. S. Kissel; S. Klimenko; K. Kokeyama; V. Kondrashov; S. Koranda; W. Z. Korth; I. Kowalska

2012-04-25T23:59:59.000Z

191

A geometric algorithm for efficient coincident detection of gravitational waves

Data from a network of gravitational wave detectors can be analyzed in coincidence to increase detection confidence and reduce non-stationarity of the background. We propose and explore a geometric algorithm to combine the data from a network of detectors. The algorithm makes optimal use of the variances and covariances that exist amongst the different parameters of a signal in a coincident detection of events. The new algorithm essentially associates with each trigger ellipsoidal regions in parameter space defined by the covariance matrix. Triggers from different detectors are deemed to be in coincidence if their ellipsoids have a non-zero overlap. Compared to an algorithm that uses uncorrelated windows separately for each of the signal parameters, the new algorithm greatly reduces the background rate thereby increasing detection efficiency at a given false alarm rate.

C. A. K. Robinson; B. S. Sathyaprakash; Anand S. Sengupta

2008-04-30T23:59:59.000Z

192

Exact impulsive gravitational waves in spacetimes of constant curvature

Exact solutions exist which describe impulsive gravitational waves propagating in Minkowski, de Sitter, or anti-de Sitter universes. These may be either nonexpanding or expanding. Both cases in each background are reviewed here from a unified point of view. All the main methods for their construction are described systematically: the Penrose "cut and paste" method, explicit construction of continuous coordinates, distributional limits of sandwich waves, embedding from higher dimensions, and boosts of sources or limits of infinite accelerations. Attention is concentrated on the most interesting specific solutions. In particular, the nonexpanding impulsive waves that are generated by null multipole particles are described. These generalize the well-known Aichelburg-Sexl and Hotta-Tanaka monopole solutions. Also described are the expanding spherical impulses that are generated by snapping and colliding strings. Geodesics and some other properties of impulsive wave spacetimes are also summarized.

J. Podolsky

2002-01-09T23:59:59.000Z

193

Localization of gravitational wave sources with networks of advanced detectors

Coincident observations with gravitational wave (GW) detectors and other astronomical instruments are among the main objectives of the experiments with the network of LIGO, Virgo, and GEO detectors. They will become a necessary part of the future GW astronomy as the next generation of advanced detectors comes online. The success of such joint observations directly depends on the source localization capabilities of the GW detectors. In this paper we present studies of the sky localization of transient GW sources with the future advanced detector networks and describe their fundamental properties. By reconstructing sky coordinates of ad hoc signals injected into simulated detector noise, we study the accuracy of the source localization and its dependence on the strength of injected signals, waveforms, and network configurations.

Klimenko, S.; Mitselmakher, G.; Pankow, C. [University of Florida, P.O. Box 118440, Gainesville, Florida, 32611 (United States); Vedovato, G. [INFN, Sezione di Padova, via Marzolo 8, 35131 Padova (Italy); Drago, M.; Prodi, G. [University of Trento, Physics Department and INFN, Gruppo Collegato di Trento, via Sommarive 14, 38123 Povo, Trento (Italy); Mazzolo, G.; Salemi, F. [Max Planck Institut fuer Gravitationsphysik, Callinstrasse 38, 30167 Hannover and Leibniz Universitaet Hannover, Hannover (Germany); Re, V. [INFN, Sezione di Roma Tor Vergata, Via della Ricerca Scientifica 1, 00133 Roma (Italy); Yakushin, I. [LIGO Livingston Observatory, Louisiana (United States)

2011-05-15T23:59:59.000Z

194

Detecting Vanishing Dimensions Via Primordial Gravitational Wave Astronomy

Lower-dimensionality at higher energies has manifold theoretical advantages as recently pointed out. Moreover, it appears that experimental evidence may already exists for it - a statistically significant planar alignment of events with energies higher than TeV has been observed in some earlier cosmic ray experiments. We propose a robust and independent test for this new paradigm. Since (2+1)-dimensional spacetimes have no gravitational degrees of freedom, gravity waves cannot be produced in that epoch. This places a universal maximum frequency at which primordial waves can propagate, marked by the transition between dimensions. We show that this cut-off frequency may be accessible to future gravitational wave detectors such as LISA.

Jonas R. Mureika; Dejan Stojkovic

2011-02-16T23:59:59.000Z

195

Colliding Impulsive Gravitational Waves and a Cosmological Constant

We present a space--time model of the collision of two homogeneous, plane impulsive gravitational waves (each having a delta function profile) propagating in a vacuum before collision and for which the post collision space--time has constant curvature. The profiles of the incoming waves are $k\\,\\delta(u)$ and $l\\,\\delta(v)$ where $k, l$ are real constants and $u=0, v=0$ are intersecting null hypersurfaces. The cosmological constant $\\Lambda$ in the post collision region of the space--time is given by $\\Lambda=-6\\,k\\,l$. In this sense this model collision provides a mechanism for generating a cosmological constant and therefore may be relevant to the theoretical description of dark energy.

Barrabčs, C

2015-01-01T23:59:59.000Z

196

Swift follow-up observations of candidate gravitational-wave transient events

We present the first multi-wavelength follow-up observations of two candidate gravitational-wave (GW) transient events recorded by LIGO and Virgo in their 2009-2010 science run. The events were selected with low latency by the network of GW detectors and their candidate sky locations were observed by the Swift observatory. Image transient detection was used to analyze the collected electromagnetic data, which were found to be consistent with background. Off-line analysis of the GW data alone has also established that the selected GW events show no evidence of an astrophysical origin; one of them is consistent with background and the other one was a test, part of a "blind injection challenge". With this work we demonstrate the feasibility of rapid follow-ups of GW transients and establish the sensitivity improvement joint electromagnetic and GW observations could bring. This is a first step toward an electromagnetic follow-up program in the regime of routine detections with the advanced GW instruments expected within this decade. In that regime multi-wavelength observations will play a significant role in completing the astrophysical identification of GW sources. We present the methods and results from this first combined analysis and discuss its implications in terms of sensitivity for the present and future instruments.

P. A. Evans; J. K. Fridriksson; N. Gehrels; J. Homan; J. P. Osborne; M. Siegel; A. Beardmore; P. Handbauer; J. Gelbord; J. A. Kennea; M. Smith; Q. Zhu; J. Aasi; J. Abadie; B. P. Abbott; R. Abbott; T. D. Abbott; M. Abernathy; T. Accadia; F. Acernese; C. Adams; T. Adams; P. Addesso; R. Adhikari; C. Affeldt; M. Agathos; K. Agatsuma; P. Ajith; B. Allen; A. Allocca; E. Amador Ceron; D. Amariutei; S. B. Anderson; W. G. Anderson; K. Arai; M. C. Araya; S. Ast; S. M. Aston; P. Astone; D. Atkinson; P. Aufmuth; C. Aulbert; B. E. Aylott; S. Babak; P. Baker; G. Ballardin; S. Ballmer; Y. Bao; J. C. B. Barayoga; D. Barker; F. Barone; B. Barr; L. Barsotti; M. Barsuglia; M. A. Barton; I. Bartos; R. Bassiri; M. Bastarrika; A. Basti; J. Batch; J. Bauchrowitz; Th. S. Bauer; M. Bebronne; D. Beck; B. Behnke; M. Bejger; M. G. Beker; A. S. Bell; C. Bell; I. Belopolski; M. Benacquista; J. M. Berliner; A. Bertolini; J. Betzwieser; N. Beveridge; P. T. Beyersdorf; T. Bhadbade; I. A. Bilenko; G. Billingsley; J. Birch; R. Biswas; M. Bitossi; M. A. Bizouard; E. Black; J. K. Blackburn; L. Blackburn; D. Blair; B. Bland; M. Blom; O. Bock; T. P. Bodiya; C. Bogan; C. Bond; R. Bondarescu; F. Bondu; L. Bonelli; R. Bonnand; R. Bork; M. Born; V. Boschi; S. Bose; L. Bosi; B. Bouhou; S. Braccini; C. Bradaschia; P. R. Brady; V. B. Braginsky; M. Branchesi; J. E. Brau; J. Breyer; T. Briant; D. O. Bridges; A. Brillet; M. Brinkmann; V. Brisson; M. Britzger; A. F. Brooks; D. A. Brown; T. Bulik; H. J. Bulten; A. Buonanno; J. Burguet-Castell; D. Buskulic; C. Buy; R. L. Byer; L. Cadonati; G. Cagnoli; E. Calloni; J. B. Camp; P. Campsie; K. Cannon; B. Canuel; J. Cao; C. D. Capano; F. Carbognani; L. Carbone; S. Caride; S. Caudill; M. Cavaglia; F. Cavalier; R. Cavalieri; G. Cella; C. Cepeda; E. Cesarini; T. Chalermsongsak; P. Charlton; E. Chassande-Mottin; W. Chen; X. Chen; Y. Chen; A. Chincarini; A. Chiummo; H. S. Cho; J. Chow; N. Christensen; S. S. Y. Chua; C. T. Y. Chung; S. Chung; G. Ciani; F. Clara; D. E. Clark; J. A. Clark; J. H. Clayton; F. Cleva; E. Coccia; P. -F. Cohadon; C. N. Colacino; A. Colla; M. Colombini; A. Conte; R. Conte; D. Cook; T. R. Corbitt; M. Cordier; N. Cornish; A. Corsi; C. A. Costa; M. Coughlin; J. -P. Coulon; P. Couvares; D. M. Coward; M. Cowart; D. C. Coyne; J. D. E. Creighton; T. D. Creighton; A. M. Cruise; A. Cumming; L. Cunningham; E. Cuoco; R. M. Cutler; K. Dahl; M. Damjanic; S. L. Danilishin; S. D'Antonio; K. Danzmann; V. Dattilo; B. Daudert; H. Daveloza; M. Davier; E. J. Daw; R. Day; T. Dayanga; R. De Rosa; D. DeBra; G. Debreczeni; J. Degallaix; W. Del Pozzo; T. Dent; V. Dergachev; R. DeRosa; S. Dhurandhar; L. Di Fiore; A. Di Lieto; I. Di Palma; M. Di Paolo Emilio; A. Di Virgilio; M. Diaz; A. Dietz; F. Donovan; K. L. Dooley; S. Doravari; S. Dorsher; M. Drago; R. W. P. Drever; J. C. Driggers; Z. Du; J. -C. Dumas; S. Dwyer; T. Eberle; M. Edgar; M. Edwards; A. Effler; P. Ehrens; S. Eikenberry; G. Endroczi; R. Engel; T. Etzel; K. Evans; M. Evans; T. Evans; M. Factourovich; V. Fafone; S. Fairhurst; B. F. Farr; M. Favata; D. Fazi; H. Fehrmann; D. Feldbaum; I. Ferrante; F. Ferrini; F. Fidecaro; L. S. Finn; I. Fiori; R. P. Fisher; R. Flaminio; S. Foley; E. Forsi; L. A. Forte; N. Fotopoulos; J. -D. Fournier; J. Franc; S. Franco; S. Frasca; F. Frasconi; M. Frede; M. A. Frei; Z. Frei; A. Freise; R. Frey; T. T. Fricke; D. Friedrich; P. Fritschel; V. V. Frolov; M. -K. Fujimoto; P. J. Fulda; M. Fyffe; J. Gair; M. Galimberti; L. Gammaitoni; J. Garcia; F. Garufi; M. E. Gaspar; G. Gelencser; G. Gemme; E. Genin; A. Gennai; L. A. Gergely; S. Ghosh; J. A. Giaime; S. Giampanis; K. D. Giardina; A. Giazotto; S. Gil-Casanova; C. Gill; J. Gleason; E. Goetz; G. Gonzalez; M. L. Gorodetsky; S. Gossler; R. Gouaty; C. Graef; P. B. Graff; M. Granata; A. Grant; C. Gray; R. J. S. Greenhalgh; A. M. Gretarsson; C. Griffo; H. Grote; K. Grover; S. Grunewald; G. M. Guidi; C. Guido; R. Gupta; E. K. Gustafson; R. Gustafson; J. M. Hallam; D. Hammer; G. Hammond; J. Hanks; C. Hanna; J. Hanson; J. Harms; G. M. Harry; I. W. Harry; E. D. Harstad; M. T. Hartman; K. Haughian; K. Hayama; J. -F. Hayau; J. Heefner; A. Heidmann; M. C. Heintze; H. Heitmann; P. Hello; G. Hemming; M. A. Hendry; I. S. Heng; A. W. Heptonstall; V. Herrera; M. Heurs; M. Hewitson; S. Hild; D. Hoak; K. A. Hodge; K. Holt; M. Holtrop; T. Hong; S. Hooper; J. Hough; E. J. Howell; B. Hughey; S. Husa; S. H. Huttner; T. Huynh-Dinh; D. R. Ingram; R. Inta; T. Isogai; A. Ivanov; K. Izumi; M. Jacobson; E. James; Y. J. Jang; P. Jaranowski; E. Jesse; W. W. Johnson; D. I. Jones; R. Jones; R. J. G. Jonker; L. Ju; P. Kalmus; V. Kalogera; S. Kandhasamy; G. Kang; J. B. Kanner; M. Kasprzack; R. Kasturi; E. Katsavounidis; W. Katzman; H. Kaufer; K. Kaufman; K. Kawabe; S. Kawamura; F. Kawazoe; D. Keitel; D. Kelley; W. Kells; D. G. Keppel; Z. Keresztes; A. Khalaidovski; F. Y. Khalili; E. A. Khazanov

2012-11-23T23:59:59.000Z

197

Dissipation of Modified Entropic Gravitational Energy Through Gravitational Waves

The phenomenological nature of a new gravitational type interaction between two different bodies derived from Verlinde's entropic approach to gravitation in combination with Sorkin's definition of Universe's quantum information content, is investigated. Assuming that the energy stored in this entropic gravitational field is dissipated under the form of gravitational waves and that the Heisenberg principle holds for this system, one calculates a possible value for an absolute minimum time scale in nature $\\tau=15/16 \\frac{\\Lambda^{1/2}\\hbar G}{c^4}\\sim9.27\\times10^{-105}$ seconds, which is much smaller than the Planck time $t_{P}=(\\hbar G/c^5)^{1/2}\\sim 5.38\\times10^{-44}$ seconds. This appears together with an absolute possible maximum value for Newtonian gravitational forces generated by matter $F_g=32/30\\frac{c^7}{\\Lambda \\hbar G^2}\\sim 3.84\\times 10^{165}$ Newtons, which is much higher than the gravitational field between two Planck masses separated by the Planck length $F_{gP}=c^4/G\\sim1.21\\times10^{44}$ Newtons.

Clovis Jacinto de Matos

2011-11-04T23:59:59.000Z

198

Improved Stack-Slide Searches for Gravitational-Wave Pulsars

We formulate and optimize a computational search strategy for detecting gravitational waves from isolated, previously-unknown neutron stars (that is, neutron stars with unknown sky positions, spin frequencies, and spin-down parameters). It is well known that fully coherent searches over the relevant parameter-space volumes are not computationally feasible, and so more computationally efficient methods are called for. The first step in this direction was taken by Brady & Creighton (2000), who proposed and optimized a two-stage, stack-slide search algorithm. We generalize and otherwise improve upon the Brady-Creighton scheme in several ways. Like Brady & Creighton, we consider a stack-slide scheme, but here with an arbitrary number of semi-coherent stages and with a coherent follow-up stage at the end. We find that searches with three semi-coherent stages are significantly more efficient than two-stage searches (requiring about 2-5 times less computational power for the same sensitivity) and are only slightly less efficient than searches with four or more stages. We calculate the signal-to-noise ratio required for detection, as a function of computing power and neutron star spin-down-age, using our optimized searches.

Curt Cutler; Iraj Gholami; Badri Krishnan

2005-05-17T23:59:59.000Z

199

Gravitational Waves and Scalar Perturbations from Spectator Fields

The most conventional mechanism for gravitational waves (gw) production during inflation is the amplification of vacuum metric fluctuations. In this case the gw production can be uniquely related to the inflationary expansion rate $H$. For example, a gw detection close to the present experimental limit (tensor-to-scalar ratio $r \\sim 0.1$) would indicate an inflationary expansion rate close to $10^{14} \\, {\\rm GeV}$. This conclusion, however, would be invalid if the observed gw originated from a different source. We construct and study one of the possible covariant formulations of the mechanism suggested in [43], where a spectator field $\\sigma$ with a sound speed $c_{s} \\ll 1$ acts as a source for gw during inflation. In our formulation $\\sigma$ is described by a so-called $P(X)$ Lagrangian and a non-minimal coupling to gravity. This field interacts only gravitationally with the inflaton, which has a standard action. We compute the amount of scalar and tensor density fluctuations produced by $\\sigma$ and find that, in our realization, $r$ is not enhanced with respect to the standard result but it is strongly sensitive to $c_s$, thus breaking the direct $r \\leftrightarrow H$ connection.

Matteo Biagetti; Emanuela Dimastrogiovanni; Matteo Fasiello; Marco Peloso

2014-11-12T23:59:59.000Z

200

Filtering post-Newtonian gravitational waves from coalescing binaries

Gravitational waves from inspiralling binaries are expected to be detected using a data analysis technique known as {\\it matched filtering.} This technique is applicable whenever the form of the signal is known accurately. Though we know the form of the signal precisely, we will not know {\\it a priori} its parameters. Hence it is essential to filter the raw output through a host of search templates each corresponding to different values of the parameters. The number of search templates needed in detecting the Newtonian waveform characterized by three independent parameters is itself several thousands. With the inclusion of post-Newtonian corrections the inspiral waveform will have four independent parameters and this, it was thought, would lead to an increase in the number of filters by several orders of magnitude---an unfavorable feature since it would drastically slow down data analysis. In this paper I show that by a judicious choice of signal parameters we can work, even when the first post-Newtonian corrections are included, with as many number of parameters as in the Newtonian case. In other words I demonstrate that the effective dimensionality of the signal parameter space does not change when first post-Newtonian corrections are taken into account.

B. S. Sathyaprakash

1994-11-15T23:59:59.000Z

While these samples are representative of the content of NLE

they are not comprehensive nor are they the most current set.

We encourage you to perform a real-time search of NLE

to obtain the most current and comprehensive results.

201

Increasing the sensitivity of a gravitational-wave (GW) detector improves our ability to measure the characteristics of detected sources. It also increases the number of weak signals that contribute to the data. Because ...

Regimbau, T.

202

Energy Momentum Pseudo-Tensor of Relic Gravitational Wave in Expanding Universe

We study the energy-momentum pseudo-tensor of gravitational wave, and examine the one introduced by Landau-Lifshitz for a general gravitational field and the effective one recently used in literature. In short wavelength limit after Brill-Hartle average, both lead to the same gauge invariant stress tensor of gravitational wave. For relic gravitational waves in the expanding universe, we examine two forms of pressure, $p_{gw}$ and $\\mathcal{P}_{gw}$, and trace the origin of their difference to a coupling between gravitational waves and the background matter. The difference is shown to be negligibly small for most of cosmic expansion stages starting from inflation. We demonstrate that the wave equation is equivalent to the energy conservation equation using the pressure $\\mathcal{P}_{gw}$ that includes the mentioned coupling.

Daiqin Su; Yang Zhang

2012-04-04T23:59:59.000Z

203

Search for gravitational waves associated with the August 2006 timing glitch of the Vela pulsar

The physical mechanisms responsible for pulsar timing glitches are thought to excite quasinormal mode oscillations in their parent neutron star that couple to gravitational-wave emission. In August 2006, a timing glitch ...

Barsotti, Lisa

204

Gamma-Ray, Neutrino & Gravitational Wave Detection: OG 2.5,2.6,2.7 Rapporteur

This report is based on a rapporteur talk presented at the 30th International Cosmic Ray Conference held in Merida, Mexico (July 2007), and covers three of the OG sessions devoted to neutrino, gravitational wave, and gamma-ray detection.

G. Rowell

2008-01-25T23:59:59.000Z

205

Development of techniques for quantum-enhanced laser-interferometric gravitational-wave detectors

A detailed theoretical and experimental study of techniques necessary for quantum-enhanced laser- interferometric gravitational wave (GW) detectors was carried out. The basic theory of GWs and laser-interferometric GW ...

Goda, Keisuke

2007-01-01T23:59:59.000Z

206

X-Pipeline: an analysis package for autonomous gravitational-wave burst searches

Autonomous gravitational-wave searches—fully automated analyses of data that run without human intervention or assistance—are desirable for a number of reasons. They are necessary for the rapid identification of ...

Sutton, Patrick J.

207

E-Print Network 3.0 - advanced gravitational-wave interferometric...

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

; Physics 46 Merger of binary neutron stars to a black hole: Disk mass, short gamma-ray bursts, and quasinormal mode ringing Summary: of gravitational waves by the advanced...

208

EXPLORING SHORT GAMMA-RAY BURSTS AS GRAVITATIONAL-WAVE STANDARD SIRENS

Recent observations support the hypothesis that a large fraction of "short-hard" gamma-ray bursts (SHBs) are associated with the inspiral and merger of compact binaries. Since gravitational-wave (GW) measurements of ...

Hughes, Scott A

209

The Weyl curvature tensor, the Cotton-York tensor and gravitational waves

We investigate the link between the Cotton-York tensor and its link to gravitational waves. Our study is carried out in the language of the congruence approach pioneered by Hawking and Ellis[2].

Osano, Bob

2013-01-01T23:59:59.000Z

210

Impact of backscattered light in a squeezing-enhanced interferometric gravitational-wave detector

Squeezed states of light have been recently used to improve the sensitivity of laser-interferometric gravitational-wave detectors beyond the quantum limit. To completely establish quantum engineering as a realistic option ...

Chua, S S Y

211

Einstein@Home search for periodic gravitational waves in early S5 LIGO data

This paper reports on an all-sky search for periodic gravitational waves from sources such as deformed isolated rapidly spinning neutron stars. The analysis uses 840 hours of data from 66 days of the fifth LIGO science run ...

Barsotti, Lisa

212

Einstein@Home search for periodic gravitational waves in LIGO S4 data

A search for periodic gravitational waves, from sources such as isolated rapidly spinning neutron stars, was carried out using 510 h of data from the fourth LIGO science run (S4). The search was for quasimonochromatic waves ...

Zucker, Michael E.

213

Directional Limits on Persistent Gravitational Waves Using LIGO S5 Science Data

The gravitational-wave (GW) sky may include nearby pointlike sources as well as stochastic backgrounds. We perform two directional searches for persistent GWs using data from the LIGO S5 science run: one optimized for ...

Barnum, Sam

214

Light amplification by gravitational waves in scalar-tensor theories of gravity

It is shown that the amplification of a light beam by gravitational waves in scalar-tensor theories of gravity is a first order effect in the wave amplitudes. In general relativity, instead, the effect is only of second order.

Valerio Faraoni

1996-02-29T23:59:59.000Z

215

Search for gravitational waves from binary black hole inspiral, merger, and ringdown

We present the first modeled search for gravitational waves using the complete binary black-hole gravitational waveform from inspiral through the merger and ringdown for binaries with negligible component spin. We searched ...

Barnum, Sam

216

Searches for a stochastic gravitational-wave background (SGWB) using terrestrial detectors typically involve cross-correlating data from pairs of detectors. The sensitivity of such cross-correlation analyses depends, among ...

Aasi, J.

217

First all-sky search for continuous gravitational waves from unknown sources in binary systems

We present the first results of an all-sky search for continuous gravitational waves from unknown spinning neutron stars in binary systems using LIGO and Virgo data. Using a specially developed analysis program, the TwoSpect ...

Aggarwal, Nancy

218

Compact binary systems with neutron stars or black holes are one of the most promising sources for ground-based gravitational-wave detectors. Gravitational radiation encodes rich information about source physics; thus ...

Barsotti, Lisa

219

Constraints on Cosmic Strings from the LIGO-Virgo Gravitational-Wave Detectors

Cosmic strings can give rise to a large variety of interesting astrophysical phenomena. Among them, powerful bursts of gravitational waves (GWs) produced by cusps are a promising observational signature. In this Letter we ...

Aggarwal, Nancy

220

Optical frequency standards for gravitational wave detection using satellite Doppler velocimetry

Gravitational waves imprint apparent Doppler shifts on the frequency of photons propagating between an emitter and detector of light. This forms the basis of a method to detect gravitational waves using Doppler velocimetry between pairs of satellites. Such detectors, operating in the milli-hertz gravitational frequency band, could lead to the direct detection of gravitational waves. The crucial component in such a detector is the frequency standard on board the emitting and receiving satellites. We point out that recent developments in atomic frequency standards have led to devices that are approaching the sensitivity required to detect gravitational waves from astrophysically interesting sources. The sensitivity of satellites equipped with optical frequency standards for Doppler velocimetry is examined, and a design for a robust, space-capable optical frequency standard is presented.

Vutha, Amar C

2015-01-01T23:59:59.000Z

While these samples are representative of the content of NLE

they are not comprehensive nor are they the most current set.

We encourage you to perform a real-time search of NLE

to obtain the most current and comprehensive results.

221

Alternative theories of gravity predict the presence of massive scalar, vector, and tensor gravitational wave modes in addition to the standard massless spin 2 graviton of general relativity. The deflection and frequency shift effects on light from distant sources propagating through a stochastic background of gravitational waves, containing such modes, differ from their counterparts in general relativity. Such effects are considered as a possible signature for alternative gravity in attempts to detect deviations from Einstein's gravity by astrophysical means.

Bellucci, Stefano [INFN Laboratori Nazionali di Frascati, Via Enrico Fermi 40, I-00044 Frascati (Italy); Capozziello, Salvatore; De Laurentis, Mariafelicia [Dip. di Scienze Fisiche, Universita di Napoli 'Federico II' and INFN Sez. di Napoli, Compl. Universitario Monte S. Angelo, Ed. N, Via Cinthia, I-80126 Napoli (Italy); Faraoni, Valerio [Physics Department, Bishop's University, Sherbrooke, Quebec, Canada J1M 1Z7 (Canada)

2009-05-15T23:59:59.000Z

222

Refraction index analysis of light propagation in a colliding gravitational wave spacetime

The optical medium analogy of a given spacetime was developed decades ago and has since then been widely applied to different gravitational contexts. Here we consider the case of a colliding gravitational wave spacetime, generalizing previous results concerning single gravitational pulses. Given the complexity of the nonlinear interaction of two gravitational waves in the framework of general relativity, typically leading to the formation of either horizons or singularities, the optical medium analogy proves helpful to simply capture some interesting effects of photon propagation.

Donato Bini; Andrea Geralico; Maria Haney

2014-08-29T23:59:59.000Z

223

Recent breakthroughs in numerical relativity enable one to examine the validity of the post-Newtonian expansion in the late stages of inspiral. For the comparison between post-Newtonian (PN) expansion and numerical simulations, the waveforms in terms of the spin-weighted spherical harmonics are more useful than the plus and cross polarizations, which are used for data analysis of gravitational waves. Factorized resummed waveforms achieve better agreement with numerical results than the conventional Taylor expanded post-Newtonian waveforms. In this paper, we revisit the post-Newtonian expansion of gravitational waves for a test particle of mass {mu} in circular orbit of radius r{sub 0} around a Schwarzschild black hole of mass M and derive the spherical harmonic components associated with the gravitational wave polarizations up to order v{sup 11} beyond Newtonian. Using the more accurate h{sub lm}'s computed in this work, we provide the more complete set of associated {rho}{sub lm}'s and {delta}{sub lm}'s that form important bricks in the factorized resummation of waveforms with potential applications for the construction of further improved waveforms for prototypical compact binary sources in the future. We also provide ready-to-use expressions of the 5.5PN gravitational waves polarizations h{sub +} and h{sub x} in the test-particle limit for gravitational waves data analysis applications. Additionally, we provide closed analytical expressions for 2.5PN h{sub lm}, 2PN {rho}{sub lm}, and 3PN {delta}{sub lm}, for general multipolar orders l and m in the test-particle limit. Finally, we also examine the implications of the present analysis for compact binary sources in Laser Interferometer Space Antenna.

Fujita, Ryuichi; Iyer, Bala R. [Raman Research Institute, Bangalore 560 080 (India)

2010-08-15T23:59:59.000Z

224

Recent breakthroughs in numerical relativity enable one to examine the validity of the post-Newtonian expansion in the late stages of inspiral. For the comparison between post-Newtonian (PN) expansion and numerical simulations, the waveforms in terms of the spin-weighted spherical harmonics are more useful than the plus and cross polarizations, which are used for data analysis of gravitational waves. Factorized resummed waveforms achieve better agreement with numerical results than the conventional Taylor expanded post-Newtonian waveforms. In this paper, we revisit the post-Newtonian expansion of gravitational waves for a test-particle of mass $\\m$ in circular orbit of radius $r_0$ around a Schwarzschild black hole of mass $M$ and derive the spherical harmonic components associated with the gravitational wave polarizations up to order $v^{11}$ beyond Newtonian. Using the more accurate $h_{\\ell m}$'s computed in this work, we provide the more complete set of associated $\\rho_{\\ell m}$'s and $\\delta_{\\ell m}$'s that form important bricks in the factorized resummation of waveforms with potential applications for the construction of further improved waveforms for prototypical compact binary sources in the future. We also provide ready-to-use expressions of the 5.5PN gravitational waves polarizations $h_+$ and $h_\\times$ in the test-particle limit for gravitational wave data analysis applications. Additionally, we provide closed analytical expressions for 2.5PN $h_{\\ell m}$, 2PN $\\rho_{\\ell m}$ and 3PN $\\delta_{\\ell m}$, for general multipolar orders $\\ell$ and $m$ in the test-particle limit. Finally, we also examine the implications of the present analysis for compact binary sources in Laser Interferometer Space Antenna.

Ryuichi Fujita; Bala R. Iyer

2010-09-01T23:59:59.000Z

225

A directed search for continuous Gravitational Waves from the Galactic Center

We present the results of a directed search for continuous gravitational waves from unknown, isolated neutron stars in the Galactic Center region, performed on two years of data from LIGO's fifth science run from two LIGO detectors. The search uses a semi-coherent approach, analyzing coherently 630 segments, each spanning 11.5 hours, and then incoherently combining the results of the single segments. It covers gravitational wave frequencies in a range from 78 to 496 Hz and a frequency-dependent range of first order spindown values down to -7.86 x 10^-8 Hz/s at the highest frequency. No gravitational waves were detected. We place 90% confidence upper limits on the gravitational wave amplitude of sources at the Galactic Center. Placing 90% confidence upper limits on the gravitational wave amplitude of sources at the Galactic Center, we reach ~3.35x10^-25 for frequencies near 150 Hz. These upper limits are the most constraining to date for a large-parameter-space search for continuous gravitational wave signals.

The LIGO Scientific Collaboration; The Virgo Collaboration; J. Aasi; J. Abadie; B. P. Abbott; R. Abbott; T. Abbott; M. R. Abernathy; T. Accadia; F. Acernese; C. Adams; T. Adams; R. X. Adhikari; C. Affeldt; M. Agathos; N. Aggarwal; O. D. Aguiar; P. Ajith; B. Allen; A. Allocca; E. Amador Ceron; D. Amariutei; R. A. Anderson; S. B. Anderson; W. G. Anderson; K. Arai; M. C. Araya; C. Arceneaux; J. Areeda; S. Ast; S. M. Aston; P. Astone; P. Aufmuth; C. Aulbert; L. Austin; B. E. Aylott; S. Babak; P. T. Baker; G. Ballardin; S. W. Ballmer; J. C. Barayoga; D. Barker; S. H. Barnum; F. Barone; B. Barr; L. Barsotti; M. Barsuglia; M. A. Barton; I. Bartos; R. Bassiri; A. Basti; J. Batch; J. Bauchrowitz; Th. S. Bauer; M. Bebronne; B. Behnke; M. Bejger; M. G. Beker; A. S. Bell; C. Bell; I. Belopolski; G. Bergmann; J. M. Berliner; A. Bertolini; D. Bessis; J. Betzwieser; P. T. Beyersdorf; T. Bhadbhade; I. A. Bilenko; G. Billingsley; J. Birch; M. Bitossi; M. A. Bizouard; E. Black; J. K. Blackburn; L. Blackburn; D. Blair; M. Blom; O. Bock; T. P. Bodiya; M. Boer; C. Bogan; C. Bond; F. Bondu; L. Bonelli; R. Bonnand; R. Bork; M. Born; S. Bose; L. Bosi; J. Bowers; C. Bradaschia; P. R. Brady; V. B. Braginsky; M. Branchesi; C. A. Brannen; J. E. Brau; J. Breyer; T. Briant; D. O. Bridges; A. Brillet; M. Brinkmann; V. Brisson; M. Britzger; A. F. Brooks; D. A. Brown; D. D. Brown; F. Brückner; T. Bulik; H. J. Bulten; A. Buonanno; D. Buskulic; C. Buy; R. L. Byer; L. Cadonati; G. Cagnoli; J. Calderón Bustillo; E. Calloni; J. B. Camp; P. Campsie; K. C. Cannon; B. Canuel; J. Cao; C. D. Capano; F. Carbognani; L. Carbone; S. Caride; A. Castiglia; S. Caudill; M. Cavagliá; F. Cavalier; R. Cavalieri; G. Cella; C. Cepeda; E. Cesarini; R. Chakraborty; T. Chalermsongsak; S. Chao; P. Charlton; E. Chassande-Mottin; X. Chen; Y. Chen; A. Chincarini; A. Chiummo; H. S. Cho; J. Chow; N. Christensen; Q. Chu; S. S. Y. Chua; S. Chung; G. Ciani; F. Clara; D. E. Clark; J. A. Clark; F. Cleva; E. Coccia; P. -F. Cohadon; A. Colla; M. Colombini; M. Constancio Jr; A. Conte; R. Conte; D. Cook; T. R. Corbitt; M. Cordier; N. Cornish; A. Corsi; C. A. Costa; M. W. Coughlin; J. -P. Coulon; S. Countryman; P. Couvares; D. M. Coward; M. Cowart; D. C. Coyne; K. Craig; J. D. E. Creighton; T. D. Creighton; S. G. Crowder; A. Cumming; L. Cunningham; E. Cuoco; K. Dahl; T. Dal Canton; M. Damjanic; S. L. Danilishin; S. D'Antonio; K. Danzmann; V. Dattilo; B. Daudert; H. Daveloza; M. Davier; G. S. Davies; E. J. Daw; R. Day; T. Dayanga; R. De Rosa; G. Debreczeni; J. Degallaix; W. Del Pozzo; E. Deleeuw; S. Deléglise; T. Denker; T. Dent; H. Dereli; V. Dergachev; R. DeRosa; R. DeSalvo; S. Dhurandhar; L. Di Fiore; A. Di Lieto; I. Di Palma; A. Di Virgilio; M. Díaz; A. Dietz; K. Dmitry; F. Donovan; K. L. Dooley; S. Doravari; M. Drago; R. W. P. Drever; J. C. Driggers; Z. Du; J. -C. Dumas; S. Dwyer; T. Eberle; M. Edwards; A. Effler; P. Ehrens; J. Eichholz; S. S. Eikenberry; G. Endröczi; R. Essick; T. Etzel; K. Evans; M. Evans; T. Evans; M. Factourovich; V. Fafone; S. Fairhurst; Q. Fang; B. Farr; W. Farr; M. Favata; D. Fazi; H. Fehrmann; D. Feldbaum; I. Ferrante; F. Ferrini; F. Fidecaro; L. S. Finn; I. Fiori; R. Fisher; R. Flaminio; E. Foley; S. Foley; E. Forsi; L. A. Forte; N. Fotopoulos; J. -D. Fournier; S. Franco; S. Frasca; F. Frasconi; M. Frede; M. Frei; Z. Frei; A. Freise; R. Frey; T. T. Fricke; P. Fritschel; V. V. Frolov; M. -K. Fujimoto; P. Fulda; M. Fyffe; J. Gair; L. Gammaitoni; J. Garcia; F. Garufi; N. Gehrels; G. Gemme; E. Genin; A. Gennai; L. Gergely; S. Ghosh; J. A. Giaime; S. Giampanis; K. D. Giardina; A. Giazotto; S. Gil-Casanova; C. Gill; J. Gleason; E. Goetz; R. Goetz; L. Gondan; G. González; N. Gordon; M. L. Gorodetsky; S. Gossan; S. Goßler; R. Gouaty; C. Graef; P. B. Graff; M. Granata; A. Grant; S. Gras; C. Gray; R. J. S. Greenhalgh; A. M. Gretarsson; C. Griffo; H. Grote; K. Grover; S. Grunewald; G. M. Guidi; C. Guido; K. E. Gushwa; E. K. Gustafson; R. Gustafson; B. Hall; E. Hall; D. Hammer; G. Hammond; M. Hanke; J. Hanks; C. Hanna; J. Hanson; J. Harms; G. M. Harry; I. W. Harry; E. D. Harstad; M. T. Hartman; K. Haughian; K. Hayama; J. Heefner; A. Heidmann; M. Heintze; H. Heitmann; P. Hello; G. Hemming; M. Hendry; I. S. Heng; A. W. Heptonstall; M. Heurs; S. Hild; D. Hoak; K. A. Hodge; K. Holt; M. Holtrop; T. Hong; S. Hooper; T. Horrom; D. J. Hosken; J. Hough; E. J. Howell; Y. Hu; Z. Hua; V. Huang; E. A. Huerta; B. Hughey; S. Husa; S. H. Huttner; M. Huynh; T. Huynh-Dinh; J. Iafrate; D. R. Ingram; R. Inta; T. Isogai; A. Ivanov; B. R. Iyer; K. Izumi; M. Jacobson; E. James; H. Jang; Y. J. Jang; P. Jaranowski; F. Jiménez-Forteza; W. W. Johnson; D. Jones; D. I. Jones; R. Jones; R. J. G. Jonker; L. Ju; Haris K; P. Kalmus; V. Kalogera; S. Kandhasamy; G. Kang; J. B. Kanner; M. Kasprzack; R. Kasturi; E. Katsavounidis; W. Katzman; H. Kaufer; K. Kaufman; K. Kawabe

2013-09-27T23:59:59.000Z

226

Swift Pointing and the Association Between Gamma-Ray Bursts and Gravitational-Wave Bursts

The currently accepted model for gamma-ray burst phenomena involves the violent formation of a rapidly rotating solar mass black hole. Gravitational waves should be associated with the black-hole formation, and their detection would permit this model to be tested, the black hole progenitor (e.g., coalescing binary or collapsing stellar core) identified, and the origin of the gamma rays (within the expanding relativistic fireball or at the point of impact on the interstellar medium) located. Even upper limits on the gravitational-wave strength associated with gamma-ray bursts could constrain the gamma-ray burst model. To do any of these requires joint observations of gamma-ray burst events with gravitational and gamma-ray detectors. Here we examine how the quality of an upper limit on the gravitational-wave strength associated with gamma-ray burst observations depends on the relative orientation of the gamma-ray-burst and gravitational-wave detectors, and apply our results to the particular case of the Swift Burst-Alert Telescope (BAT) and the LIGO gravitational-wave detectors. A result of this investigation is a science-based ``figure of merit'' that can be used, together with other mission constraints, to optimize the pointing of the Swift telescope for the detection of gravitational waves associated with gamma-ray bursts.

Lee Samuel Finn; Badri Krishnan; Patrick J. Sutton

2003-04-11T23:59:59.000Z

227

Improved methods for detecting gravitational waves associated with short gamma-ray bursts

In the era of second generation ground-based gravitational wave detectors, short gamma-ray bursts (GRBs) will be among the most promising astrophysical events for joint electromagnetic and gravitational wave observation. A targeted search for gravitational wave compact binary merger signals in coincidence with short GRBs was developed and used to analyze data from the first generation LIGO and Virgo instruments. In this paper, we present improvements to this search that enhance our ability to detect gravitational wave counterparts to short GRBs. Specifically, we introduce an improved method for estimating the gravitational wave background to obtain the event significance required to make detections; implement a method of tiling extended sky regions, as required when searching for signals associated to poorly localized GRBs from Fermi Gamma-ray Burst Monitor or the InterPlanetary Network; and incorporate astrophysical knowledge about the beaming of GRB emission to restrict the search parameter space. We describe the implementation of these enhancements and demonstrate how they improve the ability to observe binary merger gravitational wave signals associated with short GRBs.

A. R. Williamson; C. Biwer; S. Fairhurst; I. W. Harry; E. Macdonald; D. Macleod; V. Predoi

2014-10-22T23:59:59.000Z

228

Search for Gravitational Wave Bursts from Six Magnetars

Soft gamma repeaters (SGRs) and anomalous X-ray pulsars (AXPs) are thought to be magnetars: neutron stars powered by extreme magnetic fields. These rare objects are characterized by repeated and sometimes spectacular gamma-ray bursts. The burst mechanism might involve crustal fractures and excitation of non-radial modes which would emit gravitational waves (GWs). We present the results of a search for GW bursts from six galactic magnetars that is sensitive to neutron star f-modes, thought to be the most efficient GW emitting oscillatory modes in compact stars. One of them, SGR 0501+4516, is likely ~1 kpc from Earth, an order of magnitude closer than magnetars targeted in previous GW searches. A second, AXP 1E 1547.0-5408, gave a burst with an estimated isotropic energy >10^{44} erg which is comparable to the giant flares. We find no evidence of GWs associated with a sample of 1279 electromagnetic triggers from six magnetars occurring between November 2006 and June 2009, in GW data from the LIGO, Virgo, and GEO600 detectors. Our lowest model-dependent GW emission energy upper limits for band- and time-limited white noise bursts in the detector sensitive band, and for f-mode ringdowns (at 1090 Hz), are 3.0x10^{44} d_1^2 erg and 1.4x10^{47} d_1^2 erg respectively, where d_1 = d_{0501} / 1 kpc and d_{0501} is the distance to SGR 0501+4516. These limits on GW emission from f-modes are an order of magnitude lower than any previous, and approach the range of electromagnetic energies seen in SGR giant flares for the first time.

J. Abadie; B. P. Abbott; R. Abbott; M. Abernathy; T. Accadia; F. Acerneseac; C. Adams; R. Adhikari; C. Affeldt; B. Allen; G. S. Allen; E. Amador Ceron; D. Amariutei; R. S. Amin; S. B. Anderson; W. G. Anderson; F. Antonuccia; K. Arai; M. A. Arain; M. C. Araya; S. M. Aston; P. Astonea; D. Atkinson; P. Aufmuth; C. Aulbert; B. E. Aylott; S. Babak; P. Baker; G. Ballardin; S. Ballmer; D. Barker; S. Barnum; F. Baroneac; B. Barr; P. Barriga; L. Barsotti; M. Barsuglia; M. A. Barton; I. Bartos; R. Bassiri; M. Bastarrika; A. Bastiab; J. Bauchrowitz; Th. S. Bauera; B. Behnke; M. G. Bekera; A. S. Bell; A. Belletoile; I. Belopolski; M. Benacquista; A. Bertolini; J. Betzwieser; N. Beveridge; P. T. Beyersdorf; I. A. Bilenko; G. Billingsley; J. Birch; S. Birindellia; R. Biswas; M. Bitossia; M. A. Bizouarda; E. Black; J. K. Blackburn; L. Blackburn; D. Blair; B. Bland; M. Bloma; O. Bock; T. P. Bodiya; C. Bogan; R. Bondarescu; F. Bondub; L. Bonelliab; R. Bonnand; R. Bork; M. Born; V. Boschia; S. Bose; L. Bosia; B. Bouhou; M. Boyle; S. Braccinia; C. Bradaschiaa; P. R. Brady; V. B. Braginsky; J. E. Brau; J. Breyer; D. O. Bridges; A. Brilleta; M. Brinkmann; V. Brissona; M. Britzger; A. F. Brooks; D. A. Brown; A. Brummit; R. Budzy?skib; T. Bulikbc; H. J. Bultenab; A. Buonanno; J. Burguet--Castell; O. Burmeister; D. Buskulic; C. Buy; R. L. Byer; L. Cadonati; G. Cagnolia; J. Cain; E. Calloniab; J. B. Camp; E. Campagnaab; P. Campsie; J. Cannizzo; K. Cannon; B. Canuel; J. Cao; C. Capano; F. Carbognani; S. Caride; S. Caudill; M. Cavagliŕ; F. Cavaliera; R. Cavalieri; G. Cellaa; C. Cepeda; E. Cesarinib; O. Chaibia; T. Chalermsongsak; E. Chalkley; P. Charlton; E. Chassande-Mottin; S. Chelkowski; Y. Chen; A. Chincarini; N. Christensen; S. S. Y. Chua; C. T. Y. Chung; S. Chung; F. Clara; D. Clark; J. Clark; J. H. Clayton; F. Clevaa; E. Cocciaab; C. N. Colacinoab; J. Colas; A. Collaab; M. Colombinib; R. Conte; D. Cook; T. R. Corbitt; N. Cornish; A. Corsia; C. A. Costa; M. Coughlin; J. -P. Coulona; D. M. Coward; D. C. Coyne; J. D. E. Creighton; T. D. Creighton; A. M. Cruise; R. M. Culter; A. Cumming; L. Cunningham; E. Cuoco; K. Dahl; S. L. Danilishin; R. Dannenberg; S. D'Antonioa; K. Danzmann; K. Das; V. Dattilo; B. Daudert; H. Daveloza; M. Daviera; G. Davies; E. J. Daw; R. Day; T. Dayanga; R. De Rosaab; D. DeBra; G. Debreczeni; J. Degallaix; M. del Preteac; T. Dent; V. Dergachev; R. DeRosa; R. DeSalvo; S. Dhurandhar; L. Di Fiorea; A. Di Lietoab; I. Di Palma; M. Di Paolo Emilioac; A. Di Virgilioa; M. Díaz; A. Dietz; F. Donovan; K. L. Dooley; S. Dorsher; E. S. D. Douglas; M. Dragocd; R. W. P. Drever; J. C. Driggers; J. -C. Dumas; S. Dwyer; T. Eberle; M. Edgar; M. Edwards; A. Effler; P. Ehrens; R. Engel; T. Etzel; M. Evans; T. Evans; M. Factourovich; V. Fafoneab; S. Fairhurst; Y. Fan; B. F. Farr; D. Fazi; H. Fehrmann; D. Feldbaum; I. Ferranteab; F. Fidecaroab; L. S. Finn; I. Fiori; R. Flaminio; M. Flanigan; S. Foley; E. Forsi; L. A. Fortea; N. Fotopoulos; J. -D. Fourniera; J. Franc; S. Frascaab; F. Frasconia; M. Frede; M. Frei; Z. Frei; A. Freise; R. Frey; T. T. Fricke; D. Friedrich; P. Fritschel; V. V. Frolov; P. Fulda; M. Fyffe; M. Galimberti; L. Gammaitoniab; J. Garcia; J. A. Garofoli; F. Garufiab; M. E. Gáspár; G. Gemme; E. Genin; A. Gennaia; S. Ghosh; J. A. Giaime; S. Giampanis; K. D. Giardina; A. Giazottoa; C. Gill; E. Goetz; L. M. Goggin; G. González; M. L. Gorodetsky; S. Goßler; R. Gouaty; C. Graef; M. Granata; A. Grant; S. Gras; C. Gray; R. J. S. Greenhalgh; A. M. Gretarsson; C. Greveriea; R. Grosso; H. Grote; S. Grunewald; G. M. Guidiab; C. Guido; R. Gupta; E. K. Gustafson; R. Gustafson; B. Hage; J. M. Hallam; D. Hammer; G. Hammond; J. Hanks; C. Hanna; J. Hanson; J. Harms; G. M. Harry; I. W. Harry; E. D. Harstad; M. T. Hartman; K. Haughian; K. Hayama; J. -F. Hayaub; T. Hayler; J. Heefner; H. Heitmann; P. Helloa; M. A. Hendry; I. S. Heng; A. W. Heptonstall; V. Herrera; M. Hewitson; S. Hild; D. Hoak; K. A. Hodge; K. Holt; T. Hong; S. Hooper; D. J. Hosken; J. Hough; E. J. Howell; D. Huet; B. Hughey; S. Husa; S. H. Huttner; D. R. Ingram; R. Inta; T. Isogai; A. Ivanov; P. Jaranowskid; W. W. Johnson; D. I. Jones; G. Jones; R. Jones; L. Ju; P. Kalmus; V. Kalogera; S. Kandhasamy; J. B. Kanner; E. Katsavounidis; W. Katzman; K. Kawabe; S. Kawamura; F. Kawazoe; W. Kells; M. Kelner; D. G. Keppel; A. Khalaidovski; F. Y. Khalili; E. A. Khazanov; H. Kim; N. Kim; P. J. King; D. L. Kinzel; J. S. Kissel; S. Klimenko; V. Kondrashov; R. Kopparapu; S. Koranda; W. Z. Korth; I. Kowalskab; D. Kozak; V. Kringel; S. Krishnamurthy; B. Krishnan; A. Królakae; G. Kuehn; R. Kumar; P. Kwee; M. Landry; B. Lantz; N. Lastzka; A. Lazzarini; P. Leaci; J. Leong; I. Leonor; N. Leroya; N. Letendre; J. Li; T. G. F. Lia; N. Liguoriab; P. E. Lindquist; N. A. Lockerbie; D. Lodhia; M. Lorenzinia; V. Lorietteb; M. Lormand; G. Losurdoa

2011-04-15T23:59:59.000Z

229

Can environmental effects spoil precision gravitational-wave astrophysics?

[abridged abstract] No, within a broad class of scenarios. With the advent of gravitational-wave (GW) astronomy, environmental effects on the GW signal will eventually have to be quantified. Here we present a wide survey of the corrections due to these effects in two situations of great interest for GW astronomy: the black hole (BH) ringdown emission and the inspiral of two compact objects. We take into account various effects such as: electric charges, magnetic fields, cosmological evolution, possible deviations from General Relativity, firewalls, and various forms of matter such as accretion disks and dark matter halos. Our analysis predicts the existence of resonances dictated by the external mass distribution, which dominate the very late-time behavior of merger/ringdown waveforms. The mode structure can drastically differ from the vacuum case, yet the BH response to external perturbations is unchanged at the time scales relevant for detectors. This is because although the vacuum Schwarzschild resonances are no longer quasinormal modes of the system, they still dominate the response at intermediate times. Our results strongly suggest that both parametrized and ringdown searches should use at least two-mode templates. Our analysis of compact binaries shows that environmental effects are typically negligible for most eLISA sources, with the exception of very few special extreme mass ratio inspirals. We show in particular that accretion and hydrodynamic drag generically dominate over self-force effects for geometrically thin disks, whereas they can be safely neglected for geometrically thick disk environments, which are the most relevant for eLISA. Finally, we discuss how our ignorance of the matter surrounding compact objects implies intrinsic limits on the ability to constrain strong-field deviations from General Relativity.

Enrico Barausse; Vitor Cardoso; Paolo Pani

2014-05-24T23:59:59.000Z

230

INTO THE LAIR: GRAVITATIONAL-WAVE SIGNATURES OF DARK MATTER

The nature and properties of dark matter (DM) are both outstanding issues in physics. Besides clustering in halos, the universal character of gravity implies that self-gravitating compact DM configurations-predicted by various models-might be spread throughout the universe. Their astrophysical signature can be used to probe fundamental particle physics, or to test alternative descriptions of compact objects in active galactic nuclei. Here, we discuss the most promising dissection tool of such configurations: the inspiral of a compact stellar-size object and consequent gravitational-wave (GW) emission. The inward motion of this ''test probe'' encodes unique information about the nature of the supermassive configuration. When the probe travels through some compact region we show, within a Newtonian approximation, that the quasi-adiabatic inspiral is mainly driven by DM accretion and by dynamical friction, rather than by radiation reaction. When accretion dominates, the frequency and amplitude of the GW signal produced during the latest stages of the inspiral are nearly constant. In the exterior region we study a model in which the inspiral is driven by GW and scalar-wave emission, described at a fully relativistic level. Resonances in the energy flux appear whenever the orbital frequency matches the effective mass of the DM particle, corresponding to the excitation of the central object's quasinormal frequencies. Unexpectedly, these resonances can lead to large dephasing with respect to standard inspiral templates, to such an extent as to prevent detection with matched filtering techniques. We discuss some observational consequences of these effects for GW detection.

Macedo, Caio F. B.; Cardoso, Vitor; Crispino, Luis C. B. [Faculdade de Fisica, Universidade Federal do Para, 66075-110 Belem, Para (Brazil); Pani, Paolo [CENTRA, Departamento de Fisica, Instituto Superior Tecnico, Universidade Tecnica de Lisboa (UTL), Avenida Rovisco Pais 1, 1049 Lisboa (Portugal)

2013-09-01T23:59:59.000Z

231

With multiple observatories and missions being planned for detecting orphaned afterglows associated with gamma-ray bursts (GRBs) we emphasize the importance of developing data analysis strategies for searching their possible counterpart signals in the data of gravitational wave (GW) detectors in the advanced detector era. This is especially attractive since short hard gamma-ray bursts (SGRBs) may have compact binary coalescences involving neutron stars (CBCNSs) as their progenitors, which emit gravitational waves. Joint electromagnetic (EM) and GW observations of these objects will enrich our understanding of their beaming, energetics, galactic environment, and shed light on a host of other outstanding questions related to them. Here we recognize some of the astrophysical factors that determine what fraction of CBCNS sources can generate orphaned afterglows. Pipelines already exist that target the sky-position and time of occurrence of SGRBs, known from EM observations, to search for their counterparts in GW detector data. Modifying them to analyze extended periods of time in the GW data in the past of the afterglow detection, while targeting a single sky-position, can search for GWs from the common progenitor. We assess the improvement in GW detectability to be had from utilizing the sky-position information. We also propose a method for improving the detection efficiency of targeted searches of GW signals from the putative CBCNS sources of afterglows and short gamma ray bursts in the presence of errors in detector calibration or CBCNS waveform models used in the search. The improvement arises from searching in a wider patch of the sky even when the sky-position is known accurately from EM observations and utilizes the covariance of the errors in waveform parameters with those in the sky position.

Shaon Ghosh; Sukanta Bose

2013-08-28T23:59:59.000Z

232

Effects of mode degeneracy in the LIGO Livingston Observatory recycling cavity

We analyze the electromagnetic fields in a Pound-Drever-Hall locked, marginally unstable, Fabry-Perot cavity as a function of small changes in the cavity length during resonance. More specifically, we compare the results of a detailed numerical model with the behavior of the recycling cavity of the Laser Interferometer Gravitational-wave Observatory (LIGO) detector that is located in Livingston, Louisiana. In the interferometer's normal mode of operation, the recycling cavity is stabilized by inducing a thermal lens in the cavity mirrors with an external CO2 laser. During the study described here, this thermal compensation system was not operating, causing the cavity to be marginally optically unstable and cavity modes to become degenerate. In contrast to stable optical cavities, the modal content of the resonating beam in the uncompensated recycling cavity is significantly altered by very small cavity length changes. This modifies the error signals used to control the cavity length in such a way that the zero crossing point is no longer the point of maximum power in the cavity nor is it the point where the input beam mode in the cavity is maximized.

Andri M. Gretarsson; Erika D'Ambrosio; Valery Frolov; Brian O'Reilly; Peter K. Fritschel

2007-08-26T23:59:59.000Z

233

Sub-SQL Sensitivity via Optical Rigidity in Advanced LIGO Interferometer with Optical Losses

The ``optical springs'' regime of the signal-recycled configuration of laser interferometric gravitational-wave detectors is analyzed taking in account optical losses in the interferometer arm cavities. This regime allows to obtain sensitivity better than the Standard Quantum Limits both for a free test mass and for a conventional harmonic oscillator. The optical losses restrict the gain in sensitivity and achievable signal-to-noise ratio. Nevertheless, for parameters values planned for the Advanced LIGO gravitational-wave detector, this restriction is insignificant.

F. Ya. Khalili; V. I. Lazebny; S. P. Vyatchanin

2005-11-02T23:59:59.000Z

234

Compact binary mergers are the strongest candidates for the progenitors of Short Gamma Ray Bursts (SGRBs). If a gravitational wave (GW) signal from the compact binary merger is observed in association with a SGRB, such a synergy can help us understand many interesting aspects of these bursts. We examine the accuracies with which a world wide network of gravitational wave interferometers would measure the inclination angle (the angle between the angular momentum axis of the binary and the observer's line of sight) of the binary. We compare the projected accuracies of GW detectors to measure the inclination angle of double neutron star (DNS) and neutron star-black hole (NS-BH) binaries for different astrophysical scenarios. We find that a 5 detector network can measure the inclination angle to an accuracy of $\\sim 5.1 (2.2)$ degrees for a DNS(NS-BH) system at 200 Mpc if the direction of the source as well as the redshift is known electromagnetically. We argue as to how an accurate estimation of the inclination angle of the binary can prove to be crucial in understanding off-axis GRBs, the dynamics and the energetics of their jets, and help the searches for (possible) orphan afterglows of the SGRBs.

K. G. Arun; Hideyuki Tagoshi; Chandra Kant Mishra; Archana Pai

2014-12-15T23:59:59.000Z

235

Prospects for joint gravitational wave and short gamma-ray burst observations

We present a detailed evaluation of the expected rate of joint gravitational-wave and short gamma-ray burst (GRB) observations over the coming years. We begin by evaluating the improvement in distance sensitivity of the gravitational wave search that arises from using the GRB observation to restrict the time and sky location of the source. We argue that this gives a 25% increase in sensitivity when compared to an all-sky, all-time search, corresponding to more than doubling the number of detectable gravitational wave signals associated with GRBs. Using this, we present the expected rate of joint observations with the advanced LIGO and Virgo instruments, taking into account the expected evolution of the gravitational wave detector network. We show that in the early advanced gravitational wave detector observing runs, from 2015-2017, there is only a small chance of a joint observation. However, as the detectors approach their design sensitivities, there is a good chance of joint observations provided wide field GRB satellites, such as Fermi and the Interplanetary Network, continue operation. The rate will also depend critically upon the nature of the progenitor, with neutron star--black hole systems observable to greater distances than double neutron star systems. The relative rate of binary mergers and GRBs will depend upon the jet opening angle of GRBs. Consequently, joint observations, as well as accurate measurement of both the GRB rate and binary merger rates will allow for an improved estimation of the opening angle of GRBs.

J. Clark; H. Evans; S. Fairhurst; I. W. Harry; E. Macdonald; D. Macleod; P. J. Sutton; A. R. Williamson

2014-09-29T23:59:59.000Z

236

Prospects for joint gravitational wave and short gamma-ray burst observations

We present a detailed evaluation of the expected rate of joint gravitational-wave and short gamma-ray burst (GRB) observations over the coming years. We begin by evaluating the improvement in distance sensitivity of the gravitational wave search that arises from using the GRB observation to restrict the time and sky location of the source. We argue that this gives a 25% increase in sensitivity when compared to an all-sky, all-time search, corresponding to more than doubling the number of detectable gravitational wave signals associated with GRBs. Using this, we present the expected rate of joint observations with the advanced LIGO and Virgo instruments, taking into account the expected evolution of the gravitational wave detector network. We show that in the early advanced gravitational wave detector observing runs, from 2015-2017, there is only a small chance of a joint observation. However, as the detectors approach their design sensitivities, there is a good chance of joint observations provided wide field...

Clark, J; Fairhurst, S; Harry, I W; Macdonald, E; Macleod, D; Sutton, P J; Williamson, A R

2014-01-01T23:59:59.000Z

237

We present details of numerical simulations of the gravitational radiation produced by a first order {thermal} phase transition in the early universe. We confirm that the dominant source of gravitational waves is sound waves generated by the expanding bubbles of the low-temperature phase. We demonstrate that the sound waves have a power spectrum with power-law form between the scales set by the average bubble separation (which sets the length scale of the fluid flow $L_\\text{f}$) and the bubble wall width. The sound waves generate gravitational waves whose power spectrum also has a power-law form, at a rate proportional to $L_\\text{f}$ and the square of the fluid kinetic energy density. We identify a dimensionless parameter $\\tilde\\Omega_\\text{GW}$ characterising the efficiency of this "acoustic" gravitational wave production whose value is $8\\pi\\tilde\\Omega_\\text{GW} \\simeq 0.8 \\pm 0.1$ across all our simulations. We compare the acoustic gravitational waves with the standard prediction from the envelope approximation. Not only is the power spectrum steeper (apart from an initial transient) but the gravitational wave energy density is generically two orders of magnitude or more larger.

Mark Hindmarsh; Stephan J. Huber; Kari Rummukainen; David J. Weir

2015-04-13T23:59:59.000Z

238

We describe a hierarchical data analysis pipeline for coherently searching for gravitational wave (GW) signals from non-spinning compact binary coalescences (CBCs) in the data of multiple earth-based detectors. It assumes no prior information on the sky position of the source or the time of occurrence of its transient signals and, hence, is termed "blind". The pipeline computes the coherent network search statistic that is optimal in stationary, Gaussian noise, and allows for the computation of a suite of alternative statistics and signal-based discriminators that can improve its performance in real data. Unlike the coincident multi-detector search statistics employed so far, the coherent statistics are different in the sense that they check for the consistency of the signal amplitudes and phases in the different detectors with their different orientations and with the signal arrival times in them. The first stage of the hierarchical pipeline constructs coincidences of triggers from the multiple interferometers, by requiring their proximity in time and component masses. The second stage follows up on these coincident triggers by computing the coherent statistics. The performance of the hierarchical coherent pipeline on Gaussian data is shown to be better than the pipeline with just the first (coincidence) stage.

Sukanta Bose; Thilina Dayanga; Shaon Ghosh; Dipongkar Talukder

2011-04-14T23:59:59.000Z

239

Direct detection of gravitational waves by pulsar timing arrays will become feasible over the next few years. In the low frequency regime (10{sup -7} Hz-10{sup -9} Hz), we expect that a superposition of gravitational waves from many sources will manifest itself as an isotropic stochastic gravitational wave background. Currently, a number of techniques exist to detect such a signal; however, many detection methods are computationally challenging. Here we introduce an approximation to the full likelihood function for a pulsar timing array that results in computational savings proportional to the square of the number of pulsars in the array. Through a series of simulations we show that the approximate likelihood function reproduces results obtained from the full likelihood function. We further show, both analytically and through simulations, that, on average, this approximate likelihood function gives unbiased parameter estimates for astrophysically realistic stochastic background amplitudes.

Ellis, J. A.; Siemens, X. [Center for Gravitation, Cosmology and Astrophysics, University of Wisconsin Milwaukee, Milwaukee, WI 53211 (United States); Van Haasteren, R. [Max-Planck-Institut fuer Gravitationphysik (Albert-Einstein-Institut), D-30167 Hanover (Germany)

2013-05-20T23:59:59.000Z

240

Optical-Fiber Gravitational Wave Detector: Dynamical 3-Space Turbulence Detected

Preliminary results from an optical-fiber gravitational wave interferometric detector are reported. The detector is very small, cheap and simple to build and operate. It is assembled from readily available opto-electronic components. A parts list is given. The detector can operate in two modes: one in which only instrument noise is detected, and data from a 24 hour period is reported for this mode, and in a 2nd mode in which the gravitational waves are detected as well, and data from a 24 hour period is analysed. Comparison shows that the instrument has a high S/N ratio. The frequency spectrum of the gravitational waves shows a pink noise spectrum, from 0 to 0.1Hz.

Reginald T Cahill

2007-07-16T23:59:59.000Z

While these samples are representative of the content of NLE

they are not comprehensive nor are they the most current set.

We encourage you to perform a real-time search of NLE

to obtain the most current and comprehensive results.

241

Short Gamma Ray Bursts (SGRB) are believed to originate from the merger of two compact objects. If this scenario is correct, SGRB will be accompanied by the emission of strong gravitational waves, detectable by current or planned GW detectors, such as LIGO and Virgo. No detection of a gravitational wave has been made up to date. In this paper I will use a set of SGRB with observed redshifts to fit a model describing the cumulative number of SGRB as a function of redshift, to determine the rate of such merger events in the nearby universe. These estimations will be used to make probability statements about detecting a gravitational wave associated with a short gamma ray burst during the latest science run of LIGO/Virgo. Chance estimations for the enhanced and advanced detectors will also be made, and a comparison between the rates deduced from this work will be compared to the existing literature.

Alexander Dietz

2009-04-02T23:59:59.000Z

242

Gravitational wave momentum extraction in non-axisymmetric Robinson-Trautman spacetimes

We examine numerically the gravitational wave recoil in non-axisymmetric Robinson-Trautman spacetimes. We construct characteristic initial data for the Robinson-Trautman dynamics which are interpreted as corresponding to the early post-merger state of two boosted colliding black holes with a common apparent horizon. Our analysis is based on the Bondi-Sachs energy-momentum conservation laws which regulate the radiative transfer processes involved in the emission of gravitational waves. We evaluate the Bondi-Sachs momentum flux carried out by gravitational waves and the associated net kick velocity defined (in a zero-initial-Bondi-momentum frame) as proportional to the total gravitational wave impulse imparted on the system. The kick velocity distributions are obtained and analyzed for two distinct classes of initial data corresponding to the early post-merger state of (i) non-head-on collisions and (ii) head-on collisions of black holes. For the first class (i), the net gravitational wave momentum fluxes and associated kicks are evaluated for a given domain of parameters (incidence angle and mass ratio). Typically for the equal mass case the net gravitational wave momentum flux carried is nonzero. This last result indicates that these configurations are not connected with black hole binary inspirals or head-on collisions. We suggest that these systems might be a candidate to an approximate description of the post-merger phase of a non-head-on collision of black holes not preceded by a pre-merger inspiral phase, as for instance colliding black holes in pre-merger unbounded trajectories. For the second class (ii), head-on collisions, we compare our results, and discuss the analogies, with $1+3$ numerical relativity simulations of binary black hole inspirals and head-on collisions.

R. F. Aranha; I. Damiăo Soares; E. V. Tonini

2014-03-18T23:59:59.000Z

243

Searches for gravitational waves produced by coalescing black hole binaries with total masses $\\gtrsim25\\,$M$_\\odot$ use matched filtering with templates of short duration. Non-Gaussian noise bursts in gravitational wave detector data can mimic short signals and limit the sensitivity of these searches. Previous searches have relied on empirically designed statistics incorporating signal-to-noise ratio and signal-based vetoes to separate gravitational wave candidates from noise candidates. We report on sensitivity improvements achieved using a multivariate candidate ranking statistic derived from a supervised machine learning algorithm. We apply the random forest of bagged decision trees technique to two separate searches in the high mass $\\left( \\gtrsim25\\,\\mathrm{M}_\\odot \\right)$ parameter space. For a search which is sensitive to gravitational waves from the inspiral, merger, and ringdown (IMR) of binary black holes with total mass between $25\\,$M$_\\odot$ and $100\\,$M$_\\odot$, we find sensitive volume improvements as high as $70_{\\pm 13}-109_{\\pm 11}$\\% when compared to the previously used ranking statistic. For a ringdown-only search which is sensitive to gravitational waves from the resultant perturbed intermediate mass black hole with mass roughly between $10\\,$M$_\\odot$ and $600\\,$M$_\\odot$, we find sensitive volume improvements as high as $61_{\\pm 4}-241_{\\pm 12}$\\% when compared to the previously used ranking statistic. We also report how sensitivity improvements can differ depending on mass regime, mass ratio, and available data quality information. Finally, we describe the techniques used to tune and train the random forest classifier that can be generalized to its use in other searches for gravitational waves.

Paul T. Baker; Sarah Caudill; Kari A. Hodge; Dipongkar Talukder; Collin Capano; Neil J. Cornish

2014-12-19T23:59:59.000Z

244

The direct detection of gravitational waves will provide valuable astrophysical information about many celestial objects. The SCHENBERG has already undergone its first test run. It is expected to have its first scientific run soon. In this work a new data analysis approach is presented, called the method of independent bars, which can be used with SCHENBERG's data. We test this method through the simulation of the detection of gravitational waves. With this method we find the source's direction without the need to have all six transducers operational. Also, we show that the method is a generalization of another one, already described in the literature, known as the mode channels method.

Lenzi, Cesar H. [Departamento de Fisica, Instituto Tecnologico de Aeronautica, Campo Montenegro, Sao Jose dos Campos, SP, 12228-900 (Brazil); Departamento de Fisica, Universidade de Coimbra, Rua Larga, Coimbra, 3004-516 (Portugal); Magalhaes, Nadja S. [Centro Federal de Educacao de Tecnologica de Sao Paulo, R. Dr. Pedro Vicente 625, Sao Paulo, SP 01109-010 (Brazil); Marinho, Rubens M. Jr.; Araujo, Helmo A. B. [Departamento de Fisica, Instituto Tecnologico de Aeronautica, Campo Montenegro, Sao Jose dos Campos, SP, 12228-900 (Brazil); Costa, Cesar A.; Aguiar, Odylio D. [Departamento de Astrofisica, Instituto Nacional de Pesquisas Espaciais, Avenida dos Astronautas 1.758, Sao Jose dos Campos, SP, 12227-010 (Brazil)

2008-09-15T23:59:59.000Z

245

Gravitational wave detection by bounded cold electronic plasma in a long pipe

We intend to propose an experimental sketch to detect gravitational waves (GW) directly, using an cold electronic plasma in a long pipe. By considering an cold electronic plasma in a long pipe, the Maxwell equations in 3+1 formalism will be invoked to relate gravitational waves to the perturbations of plasma particles. It will be shown that the impact of GW on cold electronic plasma causes disturbances on the paths of the electrons. Those electrons that absorb energy from GW will pass through the potential barrier at the end of the pipe. Therefore, crossing of some electrons over the barrier will imply the existence of the GW.

O. Jalili; S. Rouhani; M. V. Takook

2013-10-15T23:59:59.000Z

246

Lorentz violation and red shift of gravitational waves in brane-worlds

In this paper we study the speed of gravitational waves in a brane world scenario and show that if the extra dimension is space-like, the speed of the propagation of such waves is greater in the bulk than that on the brane. Therefore, the 4D Lorentz invariance is broken in the gravitational sector. A comparison is also made between the red shift of such waves and those of the electromagnetic waves on the brane. Such a comparison is essential for extracting the signature of the extra dimension and thus clarifying the question of maximal velocity of gravitational waves in the bulk.

Fatemeh Ahmadi; Jafar Khodagholizadeh; H. R. Sepangi

2014-11-07T23:59:59.000Z

247

Analog quantum simulation of gravitational waves in a Bose-Einstein condensate

We show how to vary the physical properties of a Bose-Einstein condensate (BEC) in order to mimic an effective gravitational-wave spacetime. In particular, we focus in the simulation of the recently discovered creation of particles by real spacetime distortion in box-type traps. We show that, by modulating the speed of sound in the BEC, the phonons experience the effects of a simulated spacetime ripple with experimentally amenable parameters. These results will inform the experimental programme of gravitational wave astronomy with cold atoms.

Tupac Bravo; Carlos Sabín; Ivette Fuentes

2015-02-11T23:59:59.000Z

248

Application of the Hilbert-Huang Transform to the Search for Gravitational Waves

We present the application of a novel method of time-series analysis, the Hilbert-Huang Transform, to the search for gravitational waves. This algorithm is adaptive and does not impose a basis set on the data, and thus the time-frequency decomposition it provides is not limited by time-frequency uncertainty spreading. Because of its high time-frequency resolution it has important applications to both signal detection and instrumental characterization. Applications to the data analysis of the ground and space based gravitational wave detectors, LIGO and LISA, are described.

Jordan B. Camp; John K. Cannizzo; Kenji Numata

2007-01-27T23:59:59.000Z

249

Techniques for targeted Fermi-GBM follow-up of gravitational-wave events

The Advanced LIGO and Advanced Virgo ground-based gravitational-wave detectors are projected to come online 2015-2016, reaching a final sensitivity sufficient to observe dozens of binary neutron star mergers per year by 2018. We present a fully-automated, targeted search strategy for prompt gamma-ray counterparts in offline Fermi-GBM data. The multi-detector method makes use of a detailed model response of the instrument, and benefits from time and sky location information derived from the gravitational-wave signal.

Lindy Blackburn; Michael S. Briggs; Jordan Camp; Nelson Christensen; Valerie Connaughton; Peter Jenke; John Veitch

2013-05-14T23:59:59.000Z

250

Quantum Limits of Interferometer Topologies for Gravitational Radiation Detection

In order to expand the astrophysical reach of gravitational wave detectors, several interferometer topologies have been proposed to evade the thermodynamic and quantum mechanical limits in future detectors. In this work, we make a systematic comparison among them by considering their sensitivities and complexities. We numerically optimize their sensitivities by introducing a cost function that tries to maximize the broadband improvement over the sensitivity of current detectors. We find that frequency-dependent squeezed-light injection with a hundred-meter scale filter cavity yields a good broadband sensitivity, with low complexity, and good robustness against optical loss. This study gives us a guideline for the near-term experimental research programs in enhancing the performance of future gravitational-wave detectors.

Haixing Miao; Huan Yang; Rana X Adhikari; Yanbei Chen

2014-06-09T23:59:59.000Z

251

First all-sky search for continuous gravitational waves from unknown sources in binary systems

We present the first results of an all-sky search for continuous gravitational waves from unknown spinning neutron stars in binary systems using LIGO and Virgo data. Using a specially developed analysis program, the TwoSpect algorithm, the search was carried out on data from the sixth LIGO Science Run and the second and third Virgo Science Runs. The search covers a range of frequencies from 20 Hz to 520 Hz, a range of orbital periods from 2 to ~2,254 h and a frequency- and period-dependent range of frequency modulation depths from 0.277 to 100 mHz. This corresponds to a range of projected semi-major axes of the orbit from ~0.6e-3 ls to ~6,500 ls assuming the orbit of the binary is circular. While no plausible candidate gravitational wave events survive the pipeline, upper limits are set on the analyzed data. The most sensitive 95% confidence upper limit obtained on gravitational wave strain is 2.3e-24 at 217 Hz, assuming the source waves are circularly polarized. Although this search has been optimized for circular binary orbits, the upper limits obtained remain valid for orbital eccentricities as large as 0.9. In addition, upper limits are placed on continuous gravitational wave emission from the low-mass x-ray binary Scorpius X-1 between 20 Hz and 57.25 Hz.

The LIGO Scientific Collaboration; the Virgo Collaboration; J. Aasi; B. P. Abbott; R. Abbott; T. Abbott; M. R. Abernathy; T. Accadia; F. Acernese; K. Ackley; C. Adams; T. Adams; P. Addesso; R. X. Adhikari; C. Affeldt; M. Agathos; N. Aggarwal; O. D. Aguiar; A. Ain; P. Ajith; A. Alemic; B. Allen; A. Allocca; D. Amariutei; M. Andersen; R. Anderson; S. B. Anderson; W. G. Anderson; K. Arai; M. C. Araya; C. Arceneaux; J. Areeda; S. M. Aston; P. Astone; P. Aufmuth; C. Aulbert; L. Austin; B. E. Aylott; S. Babak; P. T. Baker; G. Ballardin; S. W. Ballmer; J. C. Barayoga; M. Barbet; B. C. Barish; D. Barker; F. Barone; B. Barr; L. Barsotti; M. Barsuglia; M. A. Barton; I. Bartos; R. Bassiri; A. Basti; J. C. Batch; J. Bauchrowitz; Th. S. Bauer; B. Behnke; M. Bejger; M. G. Beker; C. Belczynski; A. S. Bell; C. Bell; G. Bergmann; D. Bersanetti; A. Bertolini; J. Betzwieser; P. T. Beyersdorf; I. A. Bilenko; G. Billingsley; J. Birch; S. Biscans; M. Bitossi; M. A. Bizouard; E. Black; J. K. Blackburn; L. Blackburn; D. Blair; S. Bloemen; M. Blom; O. Bock; T. P. Bodiya; M. Boer; G. Bogaert; C. Bogan; C. Bond; F. Bondu; L. Bonelli; R. Bonnand; R. Bork; M. Born; V. Boschi; Sukanta Bose; L. Bosi; C. Bradaschia; P. R. Brady; V. B. Braginsky; M. Branchesi; J. E. Brau; T. Briant; D. O. Bridges; A. Brillet; M. Brinkmann; V. Brisson; A. F. Brooks; D. A. Brown; D. D. Brown; F. Brückner; S. Buchman; T. Bulik; H. J. Bulten; A. Buonanno; R. Burman; D. Buskulic; C. Buy; L. Cadonati; G. Cagnoli; J. Calderón Bustillo; E. Calloni; J. B. Camp; P. Campsie; K. C. Cannon; B. Canuel; J. Cao; C. D. Capano; F. Carbognani; L. Carbone; S. Caride; A. Castiglia; S. Caudill; M. Cavagliŕ; F. Cavalier; R. Cavalieri; C. Celerier; G. Cella; C. Cepeda; E. Cesarini; R. Chakraborty; T. Chalermsongsak; S. J. Chamberlin; S. Chao; P. Charlton; E. Chassande-Mottin; X. Chen; Y. Chen; A. Chincarini; A. Chiummo; H. S. Cho; J. Chow; N. Christensen; Q. Chu; S. S. Y. Chua; S. Chung; G. Ciani; F. Clara; J. A. Clark; F. Cleva; E. Coccia; P. -F. Cohadon; A. Colla; C. Collette; M. Colombini; L. Cominsky; M. Constancio Jr.; A. Conte; D. Cook; T. R. Corbitt; M. Cordier; N. Cornish; A. Corpuz; A. Corsi; C. A. Costa; M. W. Coughlin; S. Coughlin; J. -P. Coulon; S. Countryman; P. Couvares; D. M. Coward; M. Cowart; D. C. Coyne; R. Coyne; K. Craig; J. D. E. Creighton; T. D. Creighton; S. G. Crowder; A. Cumming; L. Cunningham; E. Cuoco; K. Dahl; T. Dal Canton; M. Damjanic; S. L. Danilishin; S. D'Antonio; K. Danzmann; V. Dattilo; H. Daveloza; M. Davier; G. S. Davies; E. J. Daw; R. Day; T. Dayanga; G. Debreczeni; J. Degallaix; S. Deléglise; W. Del Pozzo; T. Denker; T. Dent; H. Dereli; V. Dergachev; R. De Rosa; R. T. DeRosa; R. DeSalvo; S. Dhurandhar; M. Díaz; L. Di Fiore; A. Di Lieto; I. Di Palma; A. Di Virgilio; A. Donath; F. Donovan; K. L. Dooley; S. Doravari; S. Dossa; R. Douglas; T. P. Downes; M. Drago; R. W. P. Drever; J. C. Driggers; Z. Du; S. Dwyer; T. Eberle; T. Edo; M. Edwards; A. Effler; H. Eggenstein; P. Ehrens; J. Eichholz; S. S. Eikenberry; G. Endr?czi; R. Essick; T. Etzel; M. Evans; T. Evans; M. Factourovich; V. Fafone; S. Fairhurst; Q. Fang; S. Farinon; B. Farr; W. M. Farr; M. Favata; H. Fehrmann; M. M. Fejer; D. Feldbaum; F. Feroz; I. Ferrante; F. Ferrini; F. Fidecaro; L. S. Finn; I. Fiori; R. P. Fisher; R. Flaminio; J. -D. Fournier; S. Franco; S. Frasca; F. Frasconi; M. Frede; Z. Frei; A. Freise; R. Frey; T. T. Fricke; P. Fritschel; V. V. Frolov; P. Fulda; M. Fyffe; J. Gair; L. Gammaitoni; S. Gaonkar; F. Garufi; N. Gehrels; G. Gemme; E. Genin; A. Gennai; S. Ghosh; J. A. Giaime; K. D. Giardina; A. Giazotto; C. Gill; J. Gleason; E. Goetz; R. Goetz; L. Gondan; G. González; N. Gordon; M. L. Gorodetsky; S. Gossan; S. Goßler; R. Gouaty; C. Gräf; P. B. Graff; M. Granata; A. Grant; S. Gras; C. Gray; R. J. S. Greenhalgh; A. M. Gretarsson; P. Groot; H. Grote; K. Grover; S. Grunewald; G. M. Guidi; C. Guido; K. Gushwa; E. K. Gustafson; R. Gustafson; D. Hammer; G. Hammond; M. Hanke; J. Hanks; C. Hanna; J. Hanson; J. Harms; G. M. Harry; I. W. Harry; E. D. Harstad; M. Hart; M. T. Hartman; C. -J. Haster; K. Haughian; A. Heidmann; M. Heintze; H. Heitmann; P. Hello; G. Hemming; M. Hendry; I. S. Heng; A. W. Heptonstall; M. Heurs; M. Hewitson; S. Hild; D. Hoak; K. A. Hodge; K. Holt; S. Hooper; P. Hopkins; D. J. Hosken; J. Hough; E. J. Howell; Y. Hu; E. Huerta; B. Hughey; S. Husa; S. H. Huttner; M. Huynh; T. Huynh-Dinh; D. R. Ingram; R. Inta; T. Isogai; A. Ivanov; B. R. Iyer; K. Izumi; M. Jacobson; E. James; H. Jang; P. Jaranowski; Y. Ji; F. Jiménez-Forteza; W. W. Johnson; D. I. Jones; R. Jones; R. J. G. Jonker; L. Ju; Haris K; P. Kalmus; V. Kalogera; S. Kandhasamy; G. Kang; J. B. Kanner; J. Karlen; M. Kasprzack; E. Katsavounidis; W. Katzman; H. Kaufer; K. Kawabe; F. Kawazoe; F. Kéfélian; G. M. Keiser; D. Keitel; D. B. Kelley; W. Kells; A. Khalaidovski

2014-09-17T23:59:59.000Z

252

Connecting the Electromagnetic and Gravitational Wave Skies in the Era of Advanced LIGO

McWilliams, Princeton U. 9:30 Â 10:30 "Gravitational-wave astronomy: past, present, and future-924-7855 138 Nassau Street, Princeton, NJ 08542 #12;High Energy EM Counterparts and Capabilities Thursday, 3 Lower Energy EM Counterparts and Capabilities Friday, 4 May 2012 9:30 Â 10:30 "Needle in a Haystack

253

We present details of numerical simulations of the gravitational radiation produced by a first order {thermal} phase transition in the early universe. We confirm that the dominant source of gravitational waves is sound waves generated by the expanding bubbles of the low-temperature phase. We demonstrate that the sound waves have a power spectrum with power-law form between the scales set by the average bubble separation (which sets the length scale of the fluid flow $L_\\text{f}$) and the bubble wall width. The sound waves generate gravitational waves whose power spectrum also has a power-law form, at a rate proportional to $L_\\text{f}$ and the square of the fluid kinetic energy density. We identify a dimensionless parameter $\\tilde\\Omega_\\text{GW}$ characterising the efficiency of this "acoustic" gravitational wave production whose value is $8\\pi\\tilde\\Omega_\\text{GW} \\simeq 0.8 \\pm 0.1$ across all our simulations. We compare the acoustic gravitational waves with the standard prediction from the envelope appr...

Hindmarsh, Mark; Rummukainen, Kari; Weir, David J

2015-01-01T23:59:59.000Z

254

Search for gravitational waves associated with the gamma ray burst GRB030329 using the LIGO. Rakhmanov,33 S. R. Rao,11 K. Rawlins,12 S. Ray-Majumder,38 V. Re,32 D. Redding,11,b M. W. Regehr,11,b

Tanner, David B.

255

Search for gravitational waves associated with the InterPlanetary Network short gamma ray bursts

Search for gravitational waves associated with the InterPlanetary Network short gamma ray bursts V with short gamma ray bursts detected by the InterPlanetary Network (IPN) during LIGO's fifth science run and Virgo's first science run. The IPN localisation of short gamma ray bursts is limited to extended error

California at Berkeley, University of

256

Gravitational parity violation is a possibility motivated by particle physics, string theory and loop quantum gravity. One effect of it is amplitude birefringence of gravitational waves, whereby left and right circularly-polarized waves propagate at the same speed but with different amplitude evolution. Here we propose a test of this effect through coincident observations of gravitational waves and short gamma-ray bursts from binary mergers involving neutron stars. Such gravitational waves are highly left or right circularly-polarized due to the geometry of the merger. Using localization information from the gamma-ray burst, ground-based gravitational wave detectors can measure the distance to the source with reasonable accuracy. An electromagnetic determination of the redshift from an afterglow or host galaxy yields an independent measure of this distance. Gravitational parity violation would manifest itself as a discrepancy between these two distance measurements. We exemplify such a test by considering one specific effective theory that leads to such gravitational parity-violation, Chern-Simons gravity. We show that the advanced LIGO-Virgo network and all-sky gamma-ray telescopes can be sensitive to the propagating sector of Chern-Simons gravitational parity violation to a level roughly two orders of magnitude better than current stationary constraints from the LAGEOS satellites.

Nicolas Yunes; Richard O'Shaughnessy; Benjamin J. Owen; Stephon Alexander

2010-05-18T23:59:59.000Z

257

Gravitational Waves versus X and Gamma Ray Emission in a Short Gamma-Ray Burst

The recent progress in the understanding the physical nature of neutron star equilibrium configurations and the first observational evidence of a genuinely short gamma-ray burst, GRB 090227B, allows to give an estimate of the gravitational waves versus the X and Gamma-ray emission in a short gamma-ray burst.

F. G. Oliveira; Jorge A. Rueda; Remo Ruffini

2014-03-28T23:59:59.000Z

258

Search for long-lived gravitational-wave transients coincident with long gamma-ray bursts

Long gamma-ray bursts (GRBs) have been linked to extreme core-collapse supernovae from massive stars. Gravitational waves (GW) offer a probe of the physics behind long GRBs. We investigate models of long-lived (?10–1000??s) ...

Aggarwal, Nancy

259

Search for gravitational-wave bursts in the first year of the fifth LIGO science run

We present the results obtained from an all-sky search for gravitational-wave (GW) bursts in the 64–2000 Hz frequency range in data collected by the LIGO detectors during the first year (November 2005—November 2006) of ...

Zucker, Michael E.

260

Einstein@Home all-sky search for periodic gravitational waves in LIGO S5 data

This paper presents results of an all-sky search for periodic gravitational waves in the frequency range [50,1?190]??Hz and with frequency derivative range of ?[-20,1.1]×10[superscript -10]??Hz?s[superscript -1] for the ...

Barsotti, Lisa

While these samples are representative of the content of NLE

they are not comprehensive nor are they the most current set.

We encourage you to perform a real-time search of NLE

to obtain the most current and comprehensive results.

261

Search for Gravitational Waves Associated with ?-Ray Bursts Detected by the Interplanetary Network

We present the results of a search for gravitational waves associated with 223 ?-ray bursts (GRBs) detected by the InterPlanetary Network (IPN) in 2005–2010 during LIGO’s fifth and sixth science runs and Virgo’s first, ...

Aggarwal, Nancy

262

All-sky search for periodic gravitational waves in the full S5 LIGO data

We report on an all-sky search for periodic gravitational waves in the frequency band 50–800 Hz and with the frequency time derivative in the range of 0 through -6×10[superscript -9]??Hz/s. Such a signal could be produced ...

Barsotti, Lisa

263

We point out three correlated predictions of the axion monodromy inflation model: large amplitude of gravitational waves, suppression of power on horizon scales and on scales relevant for the formation of dwarf galaxies. While these predictions are likely generic to models with oscillations in the inflaton potential, the axion monodromy model naturally accommodates the required running spectral index through Planck-scale corrections to the inflaton potential. Applying this model to a combined data set of Planck, ACT, SPT, and WMAP low-$\\ell$ polarization cosmic microwave background (CMB) data, we find a best-fit tensor-to-scalar ratio $r_{0.05} = 0.07^{+0.05}_{-0.04}$ due to gravitational waves, which may have been observed by the BICEP2 experiment. Despite the contribution of gravitational waves, the total power on large scales (CMB power spectrum at low multipoles) is lower than the standard $\\Lambda$CDM cosmology with a power-law spectrum of initial perturbations and no gravitational waves, thus mitigating some of the tension on large scales. There is also a reduction in the matter power spectrum of 20-30\\% at scales corresponding to $k = 10~{\\rm Mpc}^{-1}$, which are relevant for dwarf galaxy formation. This will alleviate some of the unsolved small-scale structure problems in the standard $\\Lambda$CDM cosmology.

Quinn E. Minor; Manoj Kaplinghat

2014-11-03T23:59:59.000Z

264

A new gravitational wave generation algorithm for particle perturbations of the Kerr spacetime

We present a new approach to solve the 2+1 Teukolsky equation for gravitational perturbations of a Kerr black hole. Our approach relies on a new horizon penetrating, hyperboloidal foliation of Kerr spacetime and spatial compactification. In particular, we present a framework for waveform generation from point-particle perturbations. Extensive tests of a time domain implementation in the code {\\it Teukode} are presented. The code can efficiently deliver waveforms at future null infinity. As a first application of the method, we compute the gravitational waveforms from inspiraling and coalescing black-hole binaries in the large-mass-ratio limit. The smaller mass black hole is modeled as a point particle whose dynamics is driven by an effective-one-body-resummed analytical radiation reaction force. We compare the analytical angular momentum loss to the gravitational wave angular momentum flux. We find that higher-order post-Newtonian corrections are needed to improve the consistency for rapidly spinning binaries. Close to merger, the subdominant multipolar amplitudes (notably the $m=0$ ones) are enhanced for retrograde orbits with respect to prograde ones. We argue that this effect mirrors nonnegligible deviations from circularity of the dynamics during the late-plunge and merger phase. We compute the gravitational wave energy flux flowing into the black hole during the inspiral using a time-domain formalism proposed by Poisson. Finally, a self-consistent, iterative method to compute the gravitational wave fluxes at leading-order in the mass of the particle is presented. For a specific case study with $\\hat{a}$=0.9, a simulation that uses the consistent flux differs from one that uses the analytical flux by $\\sim35$ gravitational wave cycles over a total of about $250$ cycles. In this case the horizon absorption accounts for about $+5$ gravitational wave cycles.

Enno Harms; Sebastiano Bernuzzi; Alessandro Nagar; Anil Zenginoglu

2014-11-25T23:59:59.000Z

265

Searches for gravitational waves from known pulsars with S5 LIGO data

We present a search for gravitational waves from 116 known millisecond and young pulsars using data from the fifth science run of the LIGO detectors. For this search ephemerides overlapping the run period were obtained for all pulsars using radio and X-ray observations. We demonstrate an updated search method that allows for small uncertainties in the pulsar phase parameters to be included in the search. We report no signal detection from any of the targets and therefore interpret our results as upper limits on the gravitational wave signal strength. The most interesting limits are those for young pulsars. We present updated limits on gravitational radiation from the Crab pulsar, where the measured limit is now a factor of seven below the spin-down limit. This limits the power radiated via gravitational waves to be less than ~2% of the available spin-down power. For the X-ray pulsar J0537-6910 we reach the spin-down limit under the assumption that any gravitational wave signal from it stays phase locked to the X-ray pulses over timing glitches, and for pulsars J1913+1011 and J1952+3252 we are only a factor of a few above the spin-down limit. Of the recycled millisecond pulsars several of the measured upper limits are only about an order of magnitude above their spin-down limits. For these our best (lowest) upper limit on gravitational wave amplitude is 2.3x10^-26 for J1603-7202 and our best (lowest) limit on the inferred pulsar ellipticity is 7.0x10^-8 for J2124-3358.

The LIGO Scientific Collaboration; The Virgo Collaboration; B. P. Abbott; R. Abbott; F. Acernese; R. Adhikari; P. Ajith; B. Allen; G. Allen; M. Alshourbagy; R. S. Amin; S. B. Anderson; W. G. Anderson; F. Antonucci; S. Aoudia; M. A. Arain; M. Araya; H. Armandula; P. Armor; K. G. Arun; Y. Aso; S. Aston; P. Astone; P. Aufmuth; C. Aulbert; S. Babak; P. Baker; G. Ballardin; S. Ballmer; C. Barker; D. Barker; F. Barone; B. Barr; P. Barriga; L. Barsotti; M. Barsuglia; M. A. Barton; I. Bartos; R. Bassiri; M. Bastarrika; Th. S. Bauer; B. Behnke; M. Beker; M. Benacquista; J. Betzwieser; P. T. Beyersdorf; S. Bigotta; I. A. Bilenko; G. Billingsley; S. Birindelli; R. Biswas; M. A. Bizouard; E. Black; J. K. Blackburn; L. Blackburn; D. Blair; B. Bland; C. Boccara; T. P. Bodiya; L. Bogue; F. Bondu; L. Bonelli; R. Bork; V. Boschi; S. Bose; L. Bosi; S. Braccini; C. Bradaschia; P. R. Brady; V. B. Braginsky; J. E. Brau; D. O. Bridges; A. Brillet; M. Brinkmann; V. Brisson; C. Van Den Broeck; A. F. Brooks; D. A. Brown; A. Brummit; G. Brunet; R. Budzynski; T. Bulik; A. Bullington; H. J. Bulten; A. Buonanno; O. Burmeister; D. Buskulic; R. L. Byer; L. Cadonati; G. Cagnoli; E. Calloni; J. B. Camp; E. Campagna; J. Cannizzo; K. C. Cannon; B. Canuel; J. Cao; F. Carbognani; L. Cardenas; S. Caride; G. Castaldi; S. Caudill; M. Cavagliŕ; F. Cavalier; R. Cavalieri; G. Cella; C. Cepeda; E. Cesarini; T. Chalermsongsak; E. Chalkley; P. Charlton; E. Chassande-Mottin; S. Chatterji; S. Chelkowski; Y. Chen; A. Chincarini; N. Christensen; C. T. Y. Chung; D. Clark; J. Clark; J. H. Clayton; F. Cleva; E. Coccia; T. Cokelaer; C. N. Colacino; J. Colas; A. Colla; M. Colombini; R. Conte; D. Cook; T. R. C. Corbitt; C. Corda; N. Cornish; A. Corsi; J. -P. Coulon; D. Coward; D. C. Coyne; J. D. E. Creighton; T. D. Creighton; A. M. Cruise; R. M. Culter; A. Cumming; L. Cunningham; E. Cuoco; S. L. Danilishin; S. D'Antonio; K. Danzmann; A. Dari; V. Dattilo; B. Daudert; M. Davier; G. Davies; E. J. Daw; R. Day; R. De Rosa; D. DeBra; J. Degallaix; M. del Prete; V. Dergachev; S. Desai; R. DeSalvo; S. Dhurandhar; L. Di Fiore; A. Di Lieto; M. Di Paolo Emilio; A. Di Virgilio; M. Díaz; A. Dietz; F. Donovan; K. L. Dooley; E. E. Doomes; M. Drago; R. W. P. Drever; J. Dueck; I. Duke; J. -C. Dumas; J. G. Dwyer; C. Echols; M. Edgar; A. Effler; P. Ehrens; E. Espinoza; T. Etzel; M. Evans; T. Evans; V. Fafone; S. Fairhurst; Y. Faltas; Y. Fan; D. Fazi; H. Fehrmann; I. Ferrante; F. Fidecaro; L. S. Finn; I. Fiori; R. Flaminio; K. Flasch; S. Foley; C. Forrest; N. Fotopoulos; J. -D. Fournier; J. Franc; A. Franzen; S. Frasca; F. Frasconi; M. Frede; M. Frei; Z. Frei; A. Freise; R. Frey; T. Fricke; P. Fritschel; V. V. Frolov; M. Fyffe; V. Galdi; L. Gammaitoni; J. A. Garofoli; F. Garufi; G. Gemme; E. Genin; A. Gennai; I. Gholami; J. A. Giaime; S. Giampanis; K. D. Giardina; A. Giazotto; K. Goda; E. Goetz; L. M. Goggin; G. González; M. L. Gorodetsky; S. Goßler; R. Gouaty; M. Granata; V. Granata; A. Grant; S. Gras; C. Gray; M. Gray; R. J. S. Greenhalgh; A. M. Gretarsson; C. Greverie; F. Grimaldi; R. Grosso; H. Grote; S. Grunewald; M. Guenther; G. Guidi; E. K. Gustafson; R. Gustafson; B. Hage; J. M. Hallam; D. Hammer; G. D. Hammond; C. Hanna; J. Hanson; J. Harms; G. M. Harry; I. W. Harry; E. D. Harstad; K. Haughian; K. Hayama; J. Heefner; H. Heitmann; P. Hello; I. S. Heng; A. Heptonstall; M. Hewitson; S. Hild; E. Hirose; D. Hoak; K. A. Hodge; K. Holt; D. J. Hosken; J. Hough; D. Hoyland; D. Huet; B. Hughey; S. H. Huttner; D. R. Ingram; T. Isogai; M. Ito; A. Ivanov; P. Jaranowski; B. Johnson; W. W. Johnson; D. I. Jones; G. Jones; R. Jones; L. Sancho de la Jordana; L. Ju; P. Kalmus; V. Kalogera; S. Kandhasamy; J. Kanner; D. Kasprzyk; E. Katsavounidis; K. Kawabe; S. Kawamura; F. Kawazoe; W. Kells; D. G. Keppel; A. Khalaidovski; F. Y. Khalili; R. Khan; E. Khazanov; P. King; J. S. Kissel; S. Klimenko; K. Kokeyama; V. Kondrashov; R. Kopparapu; S. Koranda; I. Kowalska; D. Kozak; B. Krishnan; A. Królak; R. Kumar; P. Kwee; P. La Penna; P. K. Lam; M. Landry; B. Lantz; A. Lazzarini; H. Lei; M. Lei; N. Leindecker; I. Leonor; N. Leroy; N. Letendre; C. Li; H. Lin; P. E. Lindquist; T. B. Littenberg; N. A. Lockerbie; D. Lodhia; M. Longo; M. Lorenzini; V. Loriette; M. Lormand; G. Losurdo; P. Lu; M. Lubinski; A. Lucianetti; H. Lück; B. Machenschalk; M. MacInnis; J. -M. Mackowski; M. Mageswaran; K. Mailand; E. Majorana; N. Man; I. Mandel; V. Mandic; M. Mantovani; F. Marchesoni; F. Marion; S. Márka; Z. Márka; A. Markosyan; J. Markowitz; E. Maros; J. Marque; F. Martelli; I. W. Martin; R. M. Martin; J. N. Marx; K. Mason; A. Masserot; F. Matichard; L. Matone; R. A. Matzner; N. Mavalvala; R. McCarthy; D. E. McClelland; S. C. McGuire; M. McHugh; G. McIntyre; D. J. A. McKechan; K. McKenzie; M. Mehmet; A. Melatos; A. C. Melissinos; G. Mendell; D. F. Menéndez; F. Menzinger

2010-02-26T23:59:59.000Z

266

Constraints on cosmic strings from the LIGO-Virgo gravitational-wave detectors

Cosmic strings can give rise to a large variety of interesting astrophysical phenomena. Among them, powerful bursts of gravitational waves (GWs) produced by cusps are a promising observational signature. In this Letter we present a search for GWs from cosmic string cusps in data collected by the LIGO and Virgo gravitational wave detectors between 2005 and 2010, with over 625 days of live time. We find no evidence of GW signals from cosmic strings. From this result, we derive new constraints on cosmic string parameters, which complement and improve existing limits from previous searches for a stochastic background of GWs from cosmic microwave background measurements and pulsar timing data. In particular, if the size of loops is given by the gravitational backreaction scale, we place upper limits on the string tension $G\\mu$ below $10^{-8}$ in some regions of the cosmic string parameter space.

J. Aasi; J. Abadie; B. P. Abbott; R. Abbott; T. Abbott; M. R. Abernathy; T. Accadia; F. Acernese; C. Adams; T. Adams; R. X. Adhikari; C. Affeldt; M. Agathos; N. Aggarwal; O. D. Aguiar; P. Ajith; B. Allen; A. Allocca; E. Amador Ceron; D. Amariutei; R. A. Anderson; S. B. Anderson; W. G. Anderson; K. Arai; M. C. Araya; C. Arceneaux; J. Areeda; S. Ast; S. M. Aston; P. Astone; P. Aufmuth; C. Aulbert; L. Austin; B. E. Aylott; S. Babak; P. T. Baker; G. Ballardin; S. W. Ballmer; J. C. Barayoga; D. Barker; S. H. Barnum; F. Barone; B. Barr; L. Barsotti; M. Barsuglia; M. A. Barton; I. Bartos; R. Bassiri; A. Basti; J. Batch; J. Bauchrowitz; Th. S. Bauer; M. Bebronne; B. Behnke; M. Bejger; M. G. Beker; A. S. Bell; C. Bell; I. Belopolski; G. Bergmann; J. M. Berliner; D. Bersanetti; A. Bertolini; D. Bessis; J. Betzwieser; P. T. Beyersdorf; T. Bhadbhade; I. A. Bilenko; G. Billingsley; J. Birch; M. Bitossi; M. A. Bizouard; E. Black; J. K. Blackburn; L. Blackburn; D. Blair; M. Blom; O. Bock; T. P. Bodiya; M. Boer; C. Bogan; C. Bond; F. Bondu; L. Bonelli; R. Bonnand; R. Bork; M. Born; V. Boschi; S. Bose; L. Bosi; J. Bowers; C. Bradaschia; P. R. Brady; V. B. Braginsky; M. Branchesi; C. A. Brannen; J. E. Brau; J. Breyer; T. Briant; D. O. Bridges; A. Brillet; M. Brinkmann; V. Brisson; M. Britzger; A. F. Brooks; D. A. Brown; D. D. Brown; F. Brückner; T. Bulik; H. J. Bulten; A. Buonanno; D. Buskulic; C. Buy; R. L. Byer; L. Cadonati; G. Cagnoli; J. Calderón Bustillo; E. Calloni; J. B. Camp; P. Campsie; K. C. Cannon; B. Canuel; J. Cao; C. D. Capano; F. Carbognani; L. Carbone; S. Caride; A. Castiglia; S. Caudill; M. Cavagliá; F. Cavalier; R. Cavalieri; G. Cella; C. Cepeda; E. Cesarini; R. Chakraborty; T. Chalermsongsak; S. Chao; P. Charlton; E. Chassande-Mottin; X. Chen; Y. Chen; A. Chincarini; A. Chiummo; H. S. Cho; J. Chow; N. Christensen; Q. Chu; S. S. Y. Chua; S. Chung; G. Ciani; F. Clara; D. E. Clark; J. A. Clark; F. Cleva; E. Coccia; P. -F. Cohadon; A. Colla; M. Colombini; M. Constancio Jr.; A. Conte; R. Conte; D. Cook; T. R. Corbitt; M. Cordier; N. Cornish; A. Corsi; C. A. Costa; M. W. Coughlin; J. -P. Coulon; S. Countryman; P. Couvares; D. M. Coward; M. Cowart; D. C. Coyne; K. Craig; J. D. E. Creighton; T. D. Creighton; S. G. Crowder; A. Cumming; L. Cunningham; E. Cuoco; K. Dahl; T. Dal Canton; M. Damjanic; S. L. Danilishin; S. D'Antonio; K. Danzmann; V. Dattilo; B. Daudert; H. Daveloza; M. Davier; G. S. Davies; E. J. Daw; R. Day; T. Dayanga; R. De Rosa; G. Debreczeni; J. Degallaix; W. Del Pozzo; E. Deleeuw; S. Deléglise; T. Denker; T. Dent; H. Dereli; V. Dergachev; R. DeRosa; R. DeSalvo; S. Dhurandhar; L. Di Fiore; A. Di Lieto; I. Di Palma; A. Di Virgilio; M. Díaz; A. Dietz; K. Dmitry; F. Donovan; K. L. Dooley; S. Doravari; M. Drago; R. W. P. Drever; J. C. Driggers; Z. Du; J. -C. Dumas; S. Dwyer; T. Eberle; M. Edwards; A. Effler; P. Ehrens; J. Eichholz; S. S. Eikenberry; G. Endröczi; R. Essick; T. Etzel; K. Evans; M. Evans; T. Evans; M. Factourovich; V. Fafone; S. Fairhurst; Q. Fang; S. Farinon; B. Farr; W. Farr; M. Favata; D. Fazi; H. Fehrmann; D. Feldbaum; I. Ferrante; F. Ferrini; F. Fidecaro; L. S. Finn; I. Fiori; R. Fisher; R. Flaminio; E. Foley; S. Foley; E. Forsi; N. Fotopoulos; J. -D. Fournier; S. Franco; S. Frasca; F. Frasconi; M. Frede; M. Frei; Z. Frei; A. Freise; R. Frey; T. T. Fricke; P. Fritschel; V. V. Frolov; M. -K. Fujimoto; P. Fulda; M. Fyffe; J. Gair; L. Gammaitoni; J. Garcia; F. Garufi; N. Gehrels; G. Gemme; E. Genin; A. Gennai; L. Gergely; S. Ghosh; J. A. Giaime; S. Giampanis; K. D. Giardina; A. Giazotto; S. Gil-Casanova; C. Gill; J. Gleason; E. Goetz; R. Goetz; L. Gondan; G. González; N. Gordon; M. L. Gorodetsky; S. Gossan; S. Goßler; R. Gouaty; C. Graef; P. B. Graff; M. Granata; A. Grant; S. Gras; C. Gray; R. J. S. Greenhalgh; A. M. Gretarsson; C. Griffo; P. Groot; H. Grote; K. Grover; S. Grunewald; G. M. Guidi; C. Guido; K. E. Gushwa; E. K. Gustafson; R. Gustafson; B. Hall; E. Hall; D. Hammer; G. Hammond; M. Hanke; J. Hanks; C. Hanna; J. Hanson; J. Harms; G. M. Harry; I. W. Harry; E. D. Harstad; M. T. Hartman; K. Haughian; K. Hayama; J. Heefner; A. Heidmann; M. Heintze; H. Heitmann; P. Hello; G. Hemming; M. Hendry; I. S. Heng; A. W. Heptonstall; M. Heurs; S. Hild; D. Hoak; K. A. Hodge; K. Holt; M. Holtrop; T. Hong; S. Hooper; T. Horrom; D. J. Hosken; J. Hough; E. J. Howell; Y. Hu; Z. Hua; V. Huang; E. A. Huerta; B. Hughey; S. Husa; S. H. Huttner; M. Huynh; T. Huynh-Dinh; J. Iafrate; D. R. Ingram; R. Inta; T. Isogai; A. Ivanov; B. R. Iyer; K. Izumi; M. Jacobson; E. James; H. Jang; Y. J. Jang; P. Jaranowski; F. Jiménez-Forteza; W. W. Johnson; D. Jones; D. I. Jones; R. Jones; R. J. G. Jonker; L. Ju; Haris K; P. Kalmus; V. Kalogera; S. Kandhasamy; G. Kang; J. B. Kanner; M. Kasprzack; R. Kasturi; E. Katsavounidis; W. Katzman; H. Kaufer; K. Kaufman; K. Kawabe; S. Kawamura; F. Kawazoe

2014-04-07T23:59:59.000Z

267

Geodesic deviations: modeling extreme mass-ratio systems and their gravitational waves

The method of geodesic deviations has been applied to derive accurate analytic approximations to geodesics in Schwarzschild space-time. The results are used to construct analytic expressions for the source terms in the Regge-Wheeler and Zerilli-Moncrief equations, which describe the propagation of gravitational waves emitted by a compact massive object moving in the Schwarzschild background space-time. The wave equations are solved numerically to provide the asymptotic form of the wave at large distances for a series of non-circular bound orbits with periastron distances up to the ISCO radius, and the power emitted in gravitational waves by the extreme-mass ratio binary system is computed. The results compare well with those of purely numerical approaches.

G. Koekoek; J. W. van Holten

2011-03-29T23:59:59.000Z

268

Noncommutative quantum mechanics of a harmonic oscillator under linearized gravitational waves

We consider the quantum dynamics of a harmonic oscillator in noncommutative space under the influence of linearized gravitational waves (GW) in the long wave-length and low-velocity limit. Following the prescription in \\cite{ncgw1} we quantize the system. The Hamiltonian of the system is solved by using standard algebraic iterative methods. The solution shows signatures of the coordinate noncommutativity via alterations in the oscillation frequency of the harmonic oscillator system from its commutative counterpart. Moreover, it is found that the response of the harmonic oscillator to periodic GW, when their frequencies match, will oscillate with a time scale imposed by the NC parameter. We expect this noncommutative signature to show up as some noise source in the GW detection experiments since the recent phenomenological upper-bounds set on spatial noncommutative parameter implies a length-scale comparable to the length-variations due to the passage of gravitational waves, detectable in the present day GW detectors.

Anirban Saha; Sunandan Gangopadhyay; Swarup Saha

2011-06-09T23:59:59.000Z

269

Nano-Hertz Gravitational Waves Searches with Interferometric Pulsar Timing Experiments

We estimate the sensitivity to nano-Hertz gravitational waves of pulsar timing experiments in which two highly-stable millisecond pulsars are tracked simultaneously with two neighboring radio telescopes that are referenced to the same time-keeping subsystem (i.e. "the clock"). By taking the difference of the two time-of-arrival residual data streams we can exactly cancel the clock noise in the combined data set, thereby enhancing the sensitivity to gravitational waves. We estimate that, in the band ($10^{-9} - 10^{-8}$) Hz, this "interferometric" pulsar timing technique can potentially improve the sensitivity to gravitational radiation by almost two orders of magnitude over that of single-telescopes. Interferometric pulsar timing experiments could be performed with neighboring pairs of antennas of the forthcoming large arraying projects.

Massimo Tinto

2011-01-20T23:59:59.000Z

270

Detecting very long-lived gravitational-wave transients lasting hours to weeks

We explore the possibility of very long-lived gravitational-wave transients (and detector artifacts) lasting hours to weeks. Such very long signals are both interesting in their own right and as a potential source of systematic error in searches for persistent signals, e.g., from a stochastic gravitational-wave background. We review possible mechanisms for emission on these time scales and discuss computational challenges associated with their detection: namely, the substantial volume of data involved in a search for very long transients can require vast computer memory and processing time. These computational difficulties can be addressed through a form of data compression known as coarse-graining, in which information about short time spans is discarded in order to reduce the computational requirements of a search. Using data compression, we demonstrate an efficient radiometer (cross-correlation) algorithm for the detection of very long transients. In the process, we identify features of a very long transie...

Thrane, Eric; Christensen, Nelson

2015-01-01T23:59:59.000Z

271

Searches for a stochastic gravitational-wave background (SGWB) using terrestrial detectors typically involve cross-correlating data from pairs of detectors. The sensitivity of such cross-correlation analyses depends, among other things, on the separation between the two detectors: the smaller the separation, the better the sensitivity. Hence, a co-located detector pair is more sensitive to a gravitational-wave background than a non-co-located detector pair. However, co-located detectors are also expected to suffer from correlated noise from instrumental and environmental effects that could contaminate the measurement of the background. Hence, methods to identify and mitigate the effects of correlated noise are necessary to achieve the potential increase in sensitivity of co-located detectors. Here we report on the first SGWB analysis using the two LIGO Hanford detectors and address the complications arising from correlated environmental noise. We apply correlated noise identification and mitigation techniques...

Aasi, J; Abbott, B P; Abbott, R; Abbott, T; Abernathy, M R; Accadia, T; Acernese, F; Adams, C; Adams, T; Addesso, P; Adhikari, R X; Affeldt, C; Agathos, M; Aggarwal, N; Aguiar, O D; Ajith, P; Allen, B; Allocca, A; Ceron, E Amado; Amariutei, D; Anderson, R A; Anderson, S B; Anderson, W G; Arai, K; Araya, M C; Arceneaux, C; Areeda, J; Ast, S; Aston, S M; Astone, P; Aufmuth, P; Aulbert, C; Austin, L; Aylott, B E; Babak, S; Baker, P T; Ballardin, G; Ballmer, S W; Barayoga, J C; Barker, D; Barnum, S H; Barone, F; Barr, B; Barsotti, L; Barsuglia, M; Barton, M A; Bartos, I; Bassiri, R; Basti, A; Batch, J; Bauchrowitz, J; Bauer, Th S; Bebronne, M; Behnke, B; Bejger, M; Beker, M G; Bell, A S; Bell, C; Belopolski, I; Bergmann, G; Berliner, J M; Bersanetti, D; Bertolini, A; Bessis, D; Betzwieser, J; Beyersdorf, P T; Bhadbhade, T; Bilenko, I A; Billingsley, G; Birch, J; Biscans, S; Bitossi, M; Bizouard, M A; Black, E; Blackburn, J K; Blackburn, L; Blair, D; Blom, M; Bock, O; Bodiya, T P; Boer, M; Bogan, C; Bond, C; Bondu, F; Bonelli, L; Bonnand, R; Bork, R; Born, M; Boschi, V; Bose, S; Bosi, L; Bowers, J; Bradaschia, C; Brady, P R; Braginsky, V B; Branchesi, M; Brannen, C A; Brau, J E; Breyer, J; Briant, T; Bridges, D O; Brillet, A; Brinkmann, M; Brisson, V; Britzger, M; Brooks, A F; Brown, D A; Brown, D D; Brückner, F; Bulik, T; Bulten, H J; Buonanno, A; Buskulic, D; Buy, C; Byer, R L; Cadonati, L; Cagnoli, G; Bustillo, J Calderó; Calloni, E; Camp, J B; Campsie, P; Cannon, K C; Canuel, B; Cao, J; Capano, C D; Carbognani, F; Carbone, L; Caride, S; Castiglia, A; Caudill, S; Cavagliŕ, M; Cavalier, F; Cavalieri, R; Cella, G; Cepeda, C; Cesarini, E; Chakraborty, R; Chalermsongsak, T; Chao, S; Charlton, P; Chassande-Mottin, E; Chen, X; Chen, Y; Chincarini, A; Chiummo, A; Cho, H S; Chow, J; Christensen, N; Chu, Q; Chua, S S Y; Chung, S; Ciani, G; Clara, F; Clark, D E; Clark, J A; Cleva, F; Coccia, E; Cohadon, P -F; Colla, A; Colombini, M; Constanci., M; Conte, A; Cook, D; Corbitt, T R; Cordier, M; Cornish, N; Corsi, A; Costa, C A; Coughlin, M W; Coulon, J -P; Countryman, S; Couvares, P; Coward, D M; Cowart, M; Coyne, D C; Craig, K; Creighton, J D E; Creighton, T D; Crowder, S G; Cumming, A; Cunningham, L; Cuoco, E; Dahl, K; Canton, T Da; Damjanic, M; Danilishin, S L; D'Antonio, S; Danzmann, K; Dattilo, V; Daudert, B; Daveloza, H; Davier, M; Davies, G S; Daw, E J; Day, R; Dayanga, T; Debreczeni, G; Degallaix, J; Deleeuw, E; Deléglise, S; Pozzo, W De; Denker, T; Dent, T; Dereli, H; Dergachev, V; DeRosa, R T; Rosa, R D; DeSalvo, R; Dhurandhar, S; Díaz, M; Dietz, A; Fiore, L D; Lieto, A D; Palma, I D; Virgilio, A D; Dmitry, K; Donovan, F; Dooley, K L; Doravari, S; Drago, M; Drever, R W P; Driggers, J C; Du, Z; Dumas, J -C; Dwyer, S; Eberle, T; Edwards, M; Effler, A; Ehrens, P; Eichholz, J; Eikenberry, S S; Endr?czi, G; Essick, R; Etzel, T; Evans, K; Evans, M; Evans, T; Factourovich, M; Fafone, V; Fairhurst, S; Fang, Q; Farr, B; Farr, W; Favata, M; Fazi, D; Fehrmann, H; Feldbaum, D; Ferrante, I; Ferrini, F; Fidecaro, F; Finn, L S; Fiori, I; Fisher, R; Flaminio, R; Foley, E; Foley, S; Forsi, E; Fotopoulos, N; Fournier, J -D; Franco, S; Frasca, S; Frasconi, F; Frede, M; Frei, M; Frei, Z; Freise, A; Frey, R; Fricke, T T; Fritschel, P; Frolov, V V; Fujimoto, M -K; Fulda, P; Fyffe, M; Gair, J; Gammaitoni, L; Garcia, J; Garufi, F; Gehrels, N; Gemme, G; Genin, E; Gennai, A; Gergely, L; Ghosh, S; Giaime, J A; Giampanis, S; Giardina, K D; Giazotto, A; Gil-Casanova, S; Gill, C; Gleason, J; Goetz, E; Goetz, R; Gondan, L; González, G; Gordon, N; Gorodetsky, M L; Gossan, S; Goßler, S; Gouaty, R; Graef, C; Graff, P B; Granata, M; Grant, A; Gras, S; Gray, C; Greenhalgh, R J S; Gretarsson, A M; Griffo, C; Grote, H; Grover, K; Grunewald, S; Guidi, G M; Guido, C; Gushwa, K E; Gustafson, E K; Gustafson, R; Hall, B; Hall, E; Hammer, D; Hammond, G; Hanke, M; Hanks, J; Hanna, C; Hanson, J; Harms, J; Harry, G M; Harry, I W; Harstad, E D; Hartman, M T; Haughian, K; Hayama, K; Heefner, J; Heidmann, A; Heintze, M; Heitmann, H; Hello, P; Hemming, G; Hendry, M; Heng, I S; Heptonstall, A W; Heurs, M; Hild, S; Hoak, D; Hodge, K A; Holt, K; Hong, T; Hooper, S; Horrom, T; Hosken, D J; Hough, J; Howell, E J; Hu, Y; Hua, Z; Huang, V; Huerta, E A; Hughey, B; Husa, S; Huttner, S H; Huynh, M; Huynh-Dinh, T; Iafrate, J; Ingram, D R; Inta, R; Isogai, T; Ivanov, A; Iyer, B R; Izumi, K; Jacobson, M; James, E; Jang, H; Jang, Y J; Jaranowski, P; Jiménez-Forteza, F; Johnson, W W; Jones, D I; Jones, D; Jones, R; Jonker, R J G; Ju, L; K, Hari; Kalmus, P; Kalogera, V; Kandhasamy, S; Kang, G; Kanner, J B; Kasprzack, M; Kasturi, R; Katsavounidis, E; Katzman, W; Kaufer, H; Kaufman, K; Kawabe, K; Kawamura, S; Kawazoe, F; Kéfélian, F; Keitel, D; Kelley, D B; Kells, W; Keppel, D G; Khalaidovski, A; Khalili, F Y; Khazanov, E A; Kim, B K; Kim, C; Kim, K; Kim, N; Kim, W; Kim, Y -M

2014-01-01T23:59:59.000Z

272

High Energy Photons, Neutrinos and Gravitational Waves from Gamma-Ray Bursts

Most of the current knowldege about GRB is based on electromagnetic observations at MeV and lower energies. Here we focus on some recent theoretical work on GRB, in particular the higher energy (GeV-TeV) photon emission, and two potentially important non-electromagnetic channels, the TeV and higher energy neutrino signals, and the gravitational wave signals expected from GRB.

P. Meszaros; S. Kobayashi; S. Razzaque; B. Zhang

2003-05-06T23:59:59.000Z

273

The Riemann Geometry of Space and Gravitational Waves With The Spin $s=1$

It is taken into account that not the Ricci tensor ${R_{il}}$ (Einstein equation), but the Riemann tensor ${R_{iklm}}$ provides the most general description of the space geometry. If ${{R_{il}}=0}$ (the space empty with matter, but it can be occupied by gravitational waves) then ${{R_{iklm}}={C_{iklm}}} $ . The tensor ${C_{iklm}}$ is the Weyl tensor, which disappears by conversion:${{R_{il}}={g^{km}}{R_{iklm}}}$ and we lose all information about the space structure, which is described by ${C_{iklm}}$ .The symmetry of ${R_{il}}$ provides the existents of gravitational waves with the spin s=2. We show that ${C_{iklm}}$ describes gravitational waves with s=1. Such gravitational waves can be created in inhomogeneous media, where the selected directions are determined by derivates of the energy-momentum tensor ${T^m}_{i,k}$ of matter. It is taken into account that gravitation is described not only by the metric tensor $g^{ik} = (1/2)(\\gamma^i \\gamma^k + \\gamma^k \\gamma^i)$, but also by the anti-symmetric tensor $\\sigma^{ik} = (i/2)({\\gamma^i}{\\gamma^k} - {\\gamma^k}{\\gamma^i})$, where ${\\gamma^k}(x)$ are Clifford matrices. We show that the tensor ${K_{ik}} = (1/4){\\sigma^{lm}} {R_{iklm}}$, is the anty-simmetric analog to the Ricci tensor. The ${K_{lm}}$ describes various kinds of space metrics, not described by the Ricci tensor. It includes the Weyl tensor ${C_{iklm}}$, because $\\sigma^{lm} {C_{lmik}}$ is not zero.

Arkady Z. Dolginov

2014-09-02T23:59:59.000Z

274

An Exact Calculation of the Energy Density of Cosmological Gravitational Waves

In this paper we calculate the Bogoliubov coefficients and the energy density of the stochastic gravitational wave background for a universe that undergoes inflation followed by radiation domination and matter domination, using a formalism that gives the Bogoliubov coefficients as continous functions of time. By making a reasonable assumption for the equation of state during reheating, we obtain in a natural way the expected high frequency cutoff in the spectral energy density.

L. E. Mendes; A. B. Henriques; R. G. Moorhouse

1994-10-24T23:59:59.000Z

275

We consider the dynamics of a charged particle interacting with background electromagnetic field under the influence of linearized gravitational waves in the long wave-length and low-velocity limit. Following the prescription in \\cite{speli}, the system is quantized and the Hamiltonian is then solved by using standard algebraic iterative methods. The solution is in conformity with the classical analysis and shows the possibility of tuning the frequency by changing the magnetic field to set up resonance.

Sunandan Gangopadhyay; Anirban Saha

2012-04-02T23:59:59.000Z

276

We point out three correlated predictions of the axion monodromy inflation model: large amplitude of gravitational waves, suppression of power on horizon scales and on scales relevant for the formation of dwarf galaxies. While these predictions are likely generic to models with oscillations in the inflaton potential, the axion monodromy model naturally accommodates the required running spectral index through Planck-scale corrections to the inflaton potential. Applying this model to a combined data set of Planck, ACT, SPT, and WMAP low-$\\ell$ polarization cosmic microwave background (CMB) data, we find a best-fit tensor-to-scalar ratio $r_{0.05} = 0.07^{+0.05}_{-0.04}$ due to gravitational waves, which may have been observed by the BICEP2 experiment. Despite the contribution of gravitational waves, the total power on large scales (CMB power spectrum at low multipoles) is lower than the standard $\\Lambda$CDM cosmology with a power-law spectrum of initial perturbations and no gravitational waves, thus mitigating some of the tension on large scales. There is also a reduction in the matter power spectrum of 20-30\\% at scales corresponding to $k = 10~{\\rm Mpc}^{-1}$, which are relevant for dwarf galaxy formation. This will alleviate some of the unsolved small-scale structure problems in the standard $\\Lambda$CDM cosmology. The inferred matter power spectrum is also found to be consistent with recent Lyman-$\\alpha$ forest data, which is in tension with the Planck-favored $\\Lambda$CDM model with power-law primordial power spectrum.

Quinn E. Minor; Manoj Kaplinghat

2015-03-08T23:59:59.000Z

277

Searches for a stochastic gravitational-wave background (SGWB) using terrestrial detectors typically involve cross-correlating data from pairs of detectors. The sensitivity of such cross-correlation analyses depends, among other things, on the separation between the two detectors: the smaller the separation, the better the sensitivity. Hence, a co-located detector pair is more sensitive to a gravitational-wave background than a non-co-located detector pair. However, co-located detectors are also expected to suffer from correlated noise from instrumental and environmental effects that could contaminate the measurement of the background. Hence, methods to identify and mitigate the effects of correlated noise are necessary to achieve the potential increase in sensitivity of co-located detectors. Here we report on the first SGWB analysis using the two LIGO Hanford detectors and address the complications arising from correlated environmental noise. We apply correlated noise identification and mitigation techniques to data taken by the two LIGO Hanford detectors, H1 and H2, during LIGO's fifth science run. At low frequencies, 40 - 460 Hz, we are unable to sufficiently mitigate the correlated noise to a level where we may confidently measure or bound the stochastic gravitational-wave signal. However, at high frequencies, 460-1000 Hz, these techniques are sufficient to set a $95%$ confidence level (C.L.) upper limit on the gravitational-wave energy density of \\Omega(f)<7.7 x 10^{-4} (f/ 900 Hz)^3, which improves on the previous upper limit by a factor of $\\sim 180$. In doing so, we demonstrate techniques that will be useful for future searches using advanced detectors, where correlated noise (e.g., from global magnetic fields) may affect even widely separated detectors.

The LIGO Scientific Collaboration; the Virgo Collaboration; J. Aasi; J. Abadie; B. P. Abbott; R. Abbott; T. Abbott; M. R. Abernathy; T. Accadia; F. Acernese; C. Adams; T. Adams; P. Addesso; R. X. Adhikari; C. Affeldt; M. Agathos; N. Aggarwal; O. D. Aguiar; P. Ajith; B. Allen; A. Allocca; E. Amado. Ceron; D. Amariutei; R. A. Anderson; S. B. Anderson; W. G. Anderson; K. Arai; M. C. Araya; C. Arceneaux; J. Areeda; S. Ast; S. M. Aston; P. Astone; P. Aufmuth; C. Aulbert; L. Austin; B. E. Aylott; S. Babak; P. T. Baker; G. Ballardin; S. W. Ballmer; J. C. Barayoga; D. Barker; S. H. Barnum; F. Barone; B. Barr; L. Barsotti; M. Barsuglia; M. A. Barton; I. Bartos; R. Bassiri; A. Basti; J. Batch; J. Bauchrowitz; Th. S. Bauer; M. Bebronne; B. Behnke; M. Bejger; M. G. Beker; A. S. Bell; C. Bell; I. Belopolski; G. Bergmann; J. M. Berliner; D. Bersanetti; A. Bertolini; D. Bessis; J. Betzwieser; P. T. Beyersdorf; T. Bhadbhade; I. A. Bilenko; G. Billingsley; J. Birch; S. Biscans; M. Bitossi; M. A. Bizouard; E. Black; J. K. Blackburn; L. Blackburn; D. Blair; M. Blom; O. Bock; T. P. Bodiya; M. Boer; C. Bogan; C. Bond; F. Bondu; L. Bonelli; R. Bonnand; R. Bork; M. Born; V. Boschi; S. Bose; L. Bosi; J. Bowers; C. Bradaschia; P. R. Brady; V. B. Braginsky; M. Branchesi; C. A. Brannen; J. E. Brau; J. Breyer; T. Briant; D. O. Bridges; A. Brillet; M. Brinkmann; V. Brisson; M. Britzger; A. F. Brooks; D. A. Brown; D. D. Brown; F. Brückner; T. Bulik; H. J. Bulten; A. Buonanno; D. Buskulic; C. Buy; R. L. Byer; L. Cadonati; G. Cagnoli; J. Calderó. Bustillo; E. Calloni; J. B. Camp; P. Campsie; K. C. Cannon; B. Canuel; J. Cao; C. D. Capano; F. Carbognani; L. Carbone; S. Caride; A. Castiglia; S. Caudill; M. Cavagliŕ; F. Cavalier; R. Cavalieri; G. Cella; C. Cepeda; E. Cesarini; R. Chakraborty; T. Chalermsongsak; S. Chao; P. Charlton; E. Chassande-Mottin; X. Chen; Y. Chen; A. Chincarini; A. Chiummo; H. S. Cho; J. Chow; N. Christensen; Q. Chu; S. S. Y. Chua; S. Chung; G. Ciani; F. Clara; D. E. Clark; J. A. Clark; F. Cleva; E. Coccia; P. -F. Cohadon; A. Colla; M. Colombini; M. Constanci. Jr.; A. Conte; D. Cook; T. R. Corbitt; M. Cordier; N. Cornish; A. Corsi; C. A. Costa; M. W. Coughlin; J. -P. Coulon; S. Countryman; P. Couvares; D. M. Coward; M. Cowart; D. C. Coyne; K. Craig; J. D. E. Creighton; T. D. Creighton; S. G. Crowder; A. Cumming; L. Cunningham; E. Cuoco; K. Dahl; T. Da. Canton; M. Damjanic; S. L. Danilishin; S. D'Antonio; K. Danzmann; V. Dattilo; B. Daudert; H. Daveloza; M. Davier; G. S. Davies; E. J. Daw; R. Day; T. Dayanga; G. Debreczeni; J. Degallaix; E. Deleeuw; S. Deléglise; W. De. Pozzo; T. Denker; T. Dent; H. Dereli; V. Dergachev; R. T. DeRosa; R. D. Rosa; R. DeSalvo; S. Dhurandhar; M. Díaz; A. Dietz; L. D. Fiore; A. D. Lieto; I. D. Palma; A. D. Virgilio; K. Dmitry; F. Donovan; K. L. Dooley; S. Doravari; M. Drago; R. W. P. Drever; J. C. Driggers; Z. Du; J. -C. Dumas; S. Dwyer; T. Eberle; M. Edwards; A. Effler; P. Ehrens; J. Eichholz; S. S. Eikenberry; G. Endr?czi; R. Essick; T. Etzel; K. Evans; M. Evans; T. Evans; M. Factourovich; V. Fafone; S. Fairhurst; Q. Fang; B. Farr; W. Farr; M. Favata; D. Fazi; H. Fehrmann; D. Feldbaum; I. Ferrante; F. Ferrini; F. Fidecaro; L. S. Finn; I. Fiori; R. Fisher; R. Flaminio; E. Foley; S. Foley; E. Forsi; N. Fotopoulos; J. -D. Fournier; S. Franco; S. Frasca; F. Frasconi; M. Frede; M. Frei; Z. Frei; A. Freise; R. Frey; T. T. Fricke; P. Fritschel; V. V. Frolov; M. -K. Fujimoto; P. Fulda; M. Fyffe; J. Gair; L. Gammaitoni; J. Garcia; F. Garufi; N. Gehrels; G. Gemme; E. Genin; A. Gennai; L. Gergely; S. Ghosh; J. A. Giaime; S. Giampanis; K. D. Giardina; A. Giazotto; S. Gil-Casanova; C. Gill; J. Gleason; E. Goetz; R. Goetz; L. Gondan; G. González; N. Gordon; M. L. Gorodetsky; S. Gossan; S. Goßler; R. Gouaty; C. Graef; P. B. Graff; M. Granata; A. Grant; S. Gras; C. Gray; R. J. S. Greenhalgh; A. M. Gretarsson; C. Griffo; H. Grote; K. Grover; S. Grunewald; G. M. Guidi; C. Guido; K. E. Gushwa; E. K. Gustafson; R. Gustafson; B. Hall; E. Hall; D. Hammer; G. Hammond; M. Hanke; J. Hanks; C. Hanna; J. Hanson; J. Harms; G. M. Harry; I. W. Harry; E. D. Harstad; M. T. Hartman; K. Haughian; K. Hayama; J. Heefner; A. Heidmann; M. Heintze; H. Heitmann; P. Hello; G. Hemming; M. Hendry; I. S. Heng; A. W. Heptonstall; M. Heurs; S. Hild; D. Hoak; K. A. Hodge; K. Holt; T. Hong; S. Hooper; T. Horrom; D. J. Hosken; J. Hough; E. J. Howell; Y. Hu; Z. Hua; V. Huang; E. A. Huerta; B. Hughey; S. Husa; S. H. Huttner; M. Huynh; T. Huynh-Dinh; J. Iafrate; D. R. Ingram; R. Inta; T. Isogai; A. Ivanov; B. R. Iyer; K. Izumi; M. Jacobson; E. James; H. Jang; Y. J. Jang; P. Jaranowski; F. Jiménez-Forteza; W. W. Johnson; D. I. Jones; D. Jones; R. Jones; R. J. G. Jonker; L. Ju; Hari. K; P. Kalmus; V. Kalogera; S. Kandhasamy; G. Kang; J. B. Kanner; M. Kasprzack; R. Kasturi; E. Katsavounidis; W. Katzman; H. Kaufer

2014-10-22T23:59:59.000Z

278

All-sky search for gravitational-wave bursts in the first joint LIGO-GEO-Virgo run

We present results from an all-sky search for unmodeled gravitational-wave bursts in the data collected by the LIGO, GEO 600 and Virgo detectors between November 2006 and October 2007. The search is performed by three ...

Weiss, Rainer

279

We apply a machine learning algorithm, the artificial neural network, to the search for gravitational-wave signals associated with short gamma-ray bursts. The multi-dimensional samples consisting of data corresponding to the statistical and physical quantities from the coherent search pipeline are fed into the artificial neural network to distinguish simulated gravitational-wave signals from background noise artifacts. Our result shows that the data classification efficiency at a fixed false alarm probability is improved by the artificial neural network in comparison to the conventional detection statistic. Therefore, this algorithm increases the distance at which a gravitational-wave signal could be observed in coincidence with a gamma-ray burst. In order to demonstrate the performance, we also evaluate a few seconds of gravitational-wave data segment using the trained networks and obtain the false alarm probability. We suggest that the artificial neural network can be a complementary method to the conventio...

Kim, Kyungmin; Hodge, Kari A; Kim, Young-Min; Lee, Chang-Hwan; Lee, Hyun Kyu; Oh, John J; Oh, Sang Hoon; Son, Edwin J

2014-01-01T23:59:59.000Z

280

Searches for gravitational-wave transients from binary black hole coalescences typically rely on one of two approaches: matched filtering with templates and morphology-independent excess power searches. Multiple algorithmic ...

Mohapatra, Satya

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281

Gravitational waves from a variety of sources are predicted to superpose to create a stochastic background. This background is expected to contain unique information from throughout the history of the Universe that is ...

Aasi, J.

282

We report results from a search for gravitational waves produced by perturbed intermediate mass black holes (IMBH) in data collected by LIGO and Virgo between 2005 and 2010. The search was sensitive to astrophysical sources ...

Aggarwal, Nancy

283

Einstein@Home all-sky search for periodic gravitational waves in LIGO S5 data

This paper presents results of an all-sky searches for periodic gravitational waves in the frequency range [50, 1190] Hz and with frequency derivative ranges of [-2 x 10^-9, 1.1 x 10^-10] Hz/s for the fifth LIGO science run (S5). The novelty of the search lies in the use of a non-coherent technique based on the Hough-transform to combine the information from coherent searches on timescales of about one day. Because these searches are very computationally intensive, they have been deployed on the Einstein@Home distributed computing project infrastructure. The search presented here is about a factor 3 more sensitive than the previous Einstein@Home search in early S5 LIGO data. The post-processing has left us with eight surviving candidates. We show that deeper follow-up studies rule each of them out. Hence, since no statistically significant gravitational wave signals have been detected, we report upper limits on the intrinsic gravitational wave amplitude h0. For example, in the 0.5 Hz-wide band at 152.5 Hz, we can exclude the presence of signals with h0 greater than 7.6 x 10^-25 with a 90% confidence level.

J. Aasi; J. Abadie; B. P. Abbott; R. Abbott; T. D. Abbott; M. Abernathy; T. Accadia; F. Acernese; C. Adams; T. Adams; P. Addesso; R. Adhikari; C. Affeldt; M. Agathos; K. Agatsuma; P. Ajith; B. Allen; A. Allocca; E. Amador Ceron; D. Amariutei; S. B. Anderson; W. G. Anderson; K. Arai; M. C. Araya; S. Ast; S. M. Aston; P. Astone; D. Atkinson; P. Aufmuth; C. Aulbert; B. E. Aylott; S. Babak; P. Baker; G. Ballardin; S. Ballmer; Y. Bao; J. C. B. Barayoga; D. Barker; F. Barone; B. Barr; L. Barsotti; M. Barsuglia; M. A. Barton; I. Bartos; R. Bassiri; M. Bastarrika; A. Basti; J. Batch; J. Bauchrowitz; Th. S. Bauer; M. Bebronne; D. Beck; B. Behnke; M. Bejger; M. G. Beker; A. S. Bell; C. Bell; I. Belopolski; M. Benacquista; J. M. Berliner; A. Bertolini; J. Betzwieser; N. Beveridge; P. T. Beyersdorf; T. Bhadbade; I. A. Bilenko; G. Billingsley; J. Birch; R. Biswas; M. Bitossi; M. A. Bizouard; E. Black; J. K. Blackburn; L. Blackburn; D. Blair; B. Bland; M. Blom; O. Bock; T. P. Bodiya; C. Bogan; C. Bond; R. Bondarescu; F. Bondu; L. Bonelli; R. Bonnand; R. Bork; M. Born; V. Boschi; S. Bose; L. Bosi; B. Bouhou; S. Braccini; C. Bradaschia; P. R. Brady; V. B. Braginsky; M. Branchesi; J. E. Brau; J. Breyer; T. Briant; D. O. Bridges; A. Brillet; M. Brinkmann; V. Brisson; M. Britzger; A. F. Brooks; D. A. Brown; T. Bulik; H. J. Bulten; A. Buonanno; J. Burguet--Castell; D. Buskulic; C. Buy; R. L. Byer; L. Cadonati; G. Cagnoli; G. Cagnoli; E. Calloni; J. B. Camp; P. Campsie; K. Cannon; B. Canuel; J. Cao; C. D. Capano; F. Carbognani; L. Carbone; S. Caride; S. Caudill; M. Cavagliŕ; F. Cavalier; R. Cavalieri; G. Cella; C. Cepeda; E. Cesarini; T. Chalermsongsak; P. Charlton; E. Chassande-Mottin; W. Chen; X. Chen; Y. Chen; A. Chincarini; A. Chiummo; H. S. Cho; J. Chow; N. Christensen; S. S. Y. Chua; C. T. Y. Chung; S. Chung; G. Ciani; F. Clara; D. E. Clark; J. A. Clark; J. H. Clayton; F. Cleva; E. Coccia; P. -F. Cohadon; C. N. Colacino; A. Colla; M. Colombini; A. Conte; R. Conte; D. Cook; T. R. Corbitt; M. Cordier; N. Cornish; A. Corsi; C. A. Costa; M. Coughlin; J. -P. Coulon; P. Couvares; D. M. Coward; M. Cowart; D. C. Coyne; J. D. E. Creighton; T. D. Creighton; A. M. Cruise; A. Cumming; L. Cunningham; E. Cuoco; R. M. Cutler; K. Dahl; M. Damjanic; S. L. Danilishin; S. D'Antonio; K. Danzmann; V. Dattilo; B. Daudert; H. Daveloza; M. Davier; E. J. Daw; R. Day; T. Dayanga; R. De Rosa; D. DeBra; G. Debreczeni; J. Degallaix; W. Del Pozzo; T. Dent; V. Dergachev; R. DeRosa; S. Dhurandhar; L. Di Fiore; A. Di Lieto; I. Di Palma; M. Di Paolo Emilio; A. Di Virgilio; M. Díaz; A. Dietz; A. Dietz; F. Donovan; K. L. Dooley; S. Doravari; S. Dorsher; M. Drago; R. W. P. Drever; J. C. Driggers; Z. Du; J. -C. Dumas; S. Dwyer; T. Eberle; M. Edgar; M. Edwards; A. Effler; P. Ehrens; G. Endröczi; R. Engel; T. Etzel; K. Evans; M. Evans; T. Evans; M. Factourovich; V. Fafone; S. Fairhurst; B. F. Farr; M. Favata; D. Fazi; H. Fehrmann; D. Feldbaum; I. Ferrante; F. Ferrini; F. Fidecaro; L. S. Finn; I. Fiori; R. P. Fisher; R. Flaminio; S. Foley; E. Forsi; N. Fotopoulos; J. -D. Fournier; J. Franc; S. Franco; S. Frasca; F. Frasconi; M. Frede; M. A. Frei; Z. Frei; A. Freise; R. Frey; T. T. Fricke; D. Friedrich; P. Fritschel; V. V. Frolov; M. -K. Fujimoto; P. J. Fulda; M. Fyffe; J. Gair; M. Galimberti; L. Gammaitoni; J. Garcia; F. Garufi; M. E. Gáspár; G. Gelencser; G. Gemme; E. Genin; A. Gennai; L. Á. Gergely; S. Ghosh; J. A. Giaime; S. Giampanis; K. D. Giardina; A. Giazotto; S. Gil-Casanova; C. Gill; J. Gleason; E. Goetz; G. González; M. L. Gorodetsky; S. Goßler; R. Gouaty; C. Graef; P. B. Graff; M. Granata; A. Grant; C. Gray; R. J. S. Greenhalgh; A. M. Gretarsson; C. Griffo; H. Grote; K. Grover; S. Grunewald; G. M. Guidi; C. Guido; R. Gupta; E. K. Gustafson; R. Gustafson; J. M. Hallam; D. Hammer; G. Hammond; J. Hanks; C. Hanna; J. Hanson; J. Harms; G. M. Harry; I. W. Harry; E. D. Harstad; M. T. Hartman; K. Haughian; K. Hayama; J. -F. Hayau; J. Heefner; A. Heidmann; H. Heitmann; P. Hello; M. A. Hendry; I. S. Heng; A. W. Heptonstall; V. Herrera; M. Heurs; M. Hewitson; S. Hild; D. Hoak; K. A. Hodge; K. Holt; M. Holtrop; T. Hong; S. Hooper; J. Hough; E. J. Howell; B. Hughey; S. Husa; S. H. Huttner; T. Huynh-Dinh; D. R. Ingram; R. Inta; T. Isogai; A. Ivanov; K. Izumi; M. Jacobson; E. James; Y. J. Jang; P. Jaranowski; E. Jesse; W. W. Johnson; D. I. Jones; R. Jones; R. J. G. Jonker; L. Ju; P. Kalmus; V. Kalogera; S. Kandhasamy; G. Kang; J. B. Kanner; M. Kasprzack; R. Kasturi; E. Katsavounidis; W. Katzman; H. Kaufer; K. Kaufman; K. Kawabe; S. Kawamura; F. Kawazoe; D. Keitel; D. Kelley; W. Kells; D. G. Keppel; Z. Keresztes; A. Khalaidovski; F. Y. Khalili; E. A. Khazanov; B. K. Kim; C. Kim; H. Kim; K. Kim; N. Kim; Y. M. Kim; P. J. King; D. L. Kinzel; J. S. Kissel; S. Klimenko; J. Kline; K. Kokeyama; V. Kondrashov; S. Koranda; W. Z. Korth; I. Kowalska

2012-08-04T23:59:59.000Z

284

Parameter Estimation of Gravitational Waves from Precessing BH-NS Inspirals with higher harmonics

Precessing black hole-neutron star (BH-NS) binaries produce a rich gravitational wave signal, encoding the binary's nature and inspiral kinematics. Using the lalinference\\_mcmc Markov-chain Monte Carlo parameter estimation code, we use two fiducial examples to illustrate how the geometry and kinematics are encoded into the modulated gravitational wave signal, using coordinates well-adapted to precession. Even for precessing binaries, we show the performance of detailed parameter estimation can be estimated by "effective" estimates: comparisons of a prototype signal with its nearest neighbors, adopting a fixed sky location and idealized two-detector network. We use detailed and effective approaches to show higher harmonics provide nonzero but small local improvement when estimating the parameters of precessing BH-NS binaries. That said, we show higher harmonics can improve parameter estimation accuracy for precessing binaries ruling out approximately-degenerate source orientations. Our work illustrates quantities gravitational wave measurements can provide, such as reliable component masses and the precise orientation of a precessing short gamma ray burst progenitor relative to the line of sight. "Effective" estimates may provide a simple way to estimate trends in the performance of parameter estimation for generic precessing BH-NS binaries in next-generation detectors. For example, our results suggest that the orbital chirp rate, precession rate, and precession geometry are roughly-independent observables, defining natural variables to organize correlations in the high-dimensional BH-NS binary parameter space.

R. O'Shaughnessy; B. Farr; E. Ochsner; H. S. Cho; V. Raymond; C. Kim; C. H. Lee

2014-04-11T23:59:59.000Z

285

Gravitational Wave Spectrums from Pole-like Inflations based on Generalized Gravity Theories

We present a general and unified formulation which can handle the classical evolution and quantum generation processes of the cosmological gravitational wave in a broad class of generalized gravity theories. Applications are made in several inflation models based on the scalar-tensor theory, the induced gravity, and the low energy effective action of string theory. The gravitational wave power spectrums based on the vacuum expectation value of the quantized fluctuating metric during the pole-like inflation stages are derived in analytic forms. Assuming that the gravity theory transits to Einstein one while the relevant scales remain in the superhorizon scale, we derive the consequent power spectrums and the directional fluctuations of the relic radiation produced by the gravitational wave. The spectrums seeded by the vacuum fluctuations in the pole-like inflation models based on the generalized gravity show a distinguished common feature which differs from the scale invariant spectrum generated in an exponential inflation in Einstein gravity which is supported by observations.

J. Hwang

1997-10-10T23:59:59.000Z

286

Gravitational wave recoils in non-axisymmetric Robinson-Trautman spacetimes

We examine the gravitational wave recoil waves and the associated net kick velocities in non-axisymmetric Robinson-Trautman spacetimes. We use characteristic initial data for the dynamics corresponding to non-head-on collisions of black holes. We make a parameter study of the kick distributions, corresponding to an extended range of the incidence angle $\\rho_0$ in the initial data. For the range of $\\rho_0$ examined ($3^{\\circ} \\leq \\rho_0 \\leq 110^{\\circ}$) the kick distributions as a function of the symmetric mass parameter $\\eta$ satisfy a law obtained from an empirical modification of the Fitchett law, with a parameter $C$ that accounts for the non-zero net gravitational momentum wave fluxes for the equal mass case. The law fits accurately the kick distributions for the range of $\\rho_0$ examined, with a rms normalized error of the order of $5 \\%$. For the equal mass case the nonzero net gravitational wave momentum flux increases as $\\rho_0$ increases, up to $\\rho_0 \\simeq 55^{\\circ}$ beyond which it decreases. The maximum net kick velocity is about $190 {\\rm km/s}$ for for the boost parameter considered. For $\\rho_0 \\geq 50^{\\circ}$ the distribution is a monotonous function of $\\eta$. The angular patterns of the gravitational waves emitted are examined. Our analysis includes the two polarization modes present in wave zone curvature.

R. F. Aranha; I. Damiăo Soares; E. V. Tonini

2014-07-16T23:59:59.000Z

287

Gravitational waves from a test particle scattered by a neutron star: Axial mode case

Using a metric perturbation method, we study gravitational waves from a test particle scattered by a spherically symmetric relativistic star. We calculate the energy spectrum and the waveform of gravitational waves for axial modes. Since metric perturbations in axial modes do not couple to the matter fluid of the star, emitted waves for a normal neutron star show only one peak in the spectrum, which corresponds to the orbital frequency at the turning point, where the gravitational field is strongest. However, for an ultracompact star (the radius $R \\lesssim 3M$), another type of resonant periodic peak appears in the spectrum. This is just because of an excitation by a scattered particle of axial quasinormal modes, which were found by Chandrasekhar and Ferrari. This excitation comes from the existence of the potential minimum inside of a star. We also find for an ultracompact star many small periodic peaks at the frequency region beyond the maximum of the potential, which would be due to a resonance of two waves reflected by two potential barriers (Regge-Wheeler type and one at the center of the star). Such resonant peaks appear neither for a normal neutron star nor for a Schwarzschild black hole. Consequently, even if we analyze the energy spectrum of gravitational waves only for axial modes, it would be possible to distinguish between an ultracompact star and a normal neutron star (or a Schwarzschild black hole).

Kazuhiro Tominaga; Motoyuki Saijo; Kei-ichi Maeda

1999-09-20T23:59:59.000Z

288

Sensitivity and noise analysis of 4 km laser interferometric gravitational wave antennae

Around the world, efforts are underway to commission several kilometer-scale laser interferometers to detect gravitational radiation. In the United States, there are two collocated interferometers in Hanford, Washington ...

Adhikari, Rana, 1974-

2004-01-01T23:59:59.000Z

289

The techniques of power recycling and signal recycling have proven as key concepts to increase the sensitivity of large-scale gravitational wave detectors by independent resonant enhancement of light power and signal sidebands within the interferometer. Developing the latter concept further, twin signal recycling was proposed as an alternative to conventional detuned signal recycling. Twin signal recycling features the narrow-band sensitivity gain of conventional detuned signal recycling but furthermore facilitates the injection of squeezed states of light, increases the detector sensitivity over a wide frequency band and requires a less complex detection scheme for optimal signal readout. These benefits come at the expense of an additional recycling mirror, thus increasing the number of degrees of freedom in the interferometer which need to be controlled. In this article we describe the development of a length sensing and control scheme and its successful application to a tabletop-scale power recycled Michelson interferometer with twin signal recycling. We were able to lock the interferometer in all relevant longitudinal degrees of freedom, enabling the long-term stable operation of the experiment. We thus laid the foundation for further investigations of this interferometer topology to evaluate its viability for the application in gravitational wave detectors.

Christian Gräf; André Thüring; Henning Vahlbruch; Karsten Danzmann; Roman Schnabel

2012-11-29T23:59:59.000Z

290

The prospects for direct measurements of inflationary gravitational waves by next generation interferometric detectors inferred from the possible detection of B-mode polarization of the cosmic microwave background are studied. We compute the spectra of the gravitational wave background and the signal-to-noise ratios by two interferometric detectors (DECIGO and BBO) for large-field inflationary models in which the tensor-to-scalar ratio is greater than the order of 0.01. If the reheating temperature $T_{\\rm RH}$ of chaotic inflation with the quadratic potential is high ($T_{\\rm RH}>7.9\\times10^6$ GeV for upgraded DECIGO and $T_{\\rm RH}> 1.8\\times 10^{6}$ GeV for BBO), it will be possible to reach the sensitivity of the gravitational background in future experiments at $3\\sigma$ confidence level. The direct detection is also possible for natural inflation with the potential $V(\\phi)=\\Lambda^4 [1-\\cos(\\phi/f)]$, provided that $f>4.2 M_{\\rm pl}$ (upgraded DECIGO) and $f>3.6 M_{\\rm pl}$ (BBO) with $T_{\\rm RH}$ higher than $10^8$ GeV. The quartic potential $V(\\phi)=\\lambda \\phi^4/4$ with a non-minimal coupling $\\xi$ between the inflaton field $\\phi$ and the Ricci scalar $R$ gives rise to a detectable level of gravitational waves for $|\\xi|$ smaller than the order of 0.01, irrespective of the reheating temperature.

Sachiko Kuroyanagi; Shinji Tsujikawa; Takeshi Chiba; Naoshi Sugiyama

2014-10-09T23:59:59.000Z

291

Gravitational waves emitted by solar-type stars excited by orbiting planets

The possibility of exciting the g-modes of a solar-type star as a consequence of the gravitational interaction with a close companion (a planet or a brown dwarf) is studied by a perturbative approach. The amplitude of the emitted gravitational wave is computed and compared with the quadrupole emission of the system, showing that in some cases it can be considerably larger. The effects of radiation reaction are considered to evaluate the timescale of the emission process, and a Roche lobe analysis is used to establish the region where the companion can orbit without being disrupted by tidal interactions with the star.

Emanuele Berti; Valeria Ferrari

2000-11-30T23:59:59.000Z

292

On the background estimation by time slides in a network of gravitational wave detectors

Time shifting the outputs of Gravitational Wave detectors operating in coincidence is a convenient way to estimate the background in a search for short duration signals. However this procedure is limited as increasing indefinitely the number of time shifts does not provide better estimates. We show that the false alarm rate estimation error saturates with the number of time shifts. In particular, for detectors with very different trigger rates this error saturates at a large value. Explicit computations are done for 2 detectors, and for 3 detectors where the detection statistic relies on the logical ``OR'' of the coincidences of the 3 couples in the network.

Michal Was; Marie-Anne Bizouard; Violette Brisson; Fabien Cavalier; Michel Davier; Patrice Hello; Nicolas Leroy; Florent Robinet; Vavoulidis Miltiadis

2009-11-25T23:59:59.000Z

293

The response of a test particle, both for the free case and under the harmonic oscillator potential, to circularly polarized gravitational waves is investigated in a noncommutative quantum mechanical setting. The system is quantized following the prescription in \\cite{ncgw1}. Standard algebraic techniques are then employed to solve the Hamiltonian of the system. The solutions, in both cases, show signatures of the coordinate noncommutativity. In the harmonic oscillator case, this signature plays a key role in altering the resonance point and the oscillation frequency of the system.

Sunandan Gangopadhyay; Anirban Saha; Swarup Saha

2014-09-11T23:59:59.000Z

294

The equations which determine the response of a spinning charged particle moving in a uniform magnetic field to an incident gravitational wave are derived in the linearized approximation to general relativity. We verify that 1) the components of the 4-momentum, 4-velocity and the components of the spinning tensor, both electric and magnetic moments, exhibit resonances and 2) the co-existence of the uniform magnetic field and the GW are responsible for the resonances appearing in our equations. In the absence of the GW, the magnetic field and the components of the spin tensor decouple and the magnetic resonances disappear.

D. B. Papadopoulos

2003-12-23T23:59:59.000Z

295

The Analysis of Large Order Bessel Functions in Gravitational Wave Signals from Pulsars

In this work, we present the analytic treatment of the large order Bessel functions that arise in the Fourier Transform (FT) of the Gravitational Wave (GW) signal from a pulsar. We outline several strategies which employ asymptotic expansions in evaluation of such Bessel functions which also happen to have large argument. Large order Bessel functions also arise in the Peters-Mathews model of binary inspiralling stars emitting GW and several problems in potential scattering theory. Other applications also arise in a variety of problems in Applied Mathematics as well as in the Natural Sciences and present a challenge for High Performance Computing(HPC).

F. A. Chishtie; S. R. Valluri; K. M. Rao; D. Sikorski; T. Williams

2005-03-15T23:59:59.000Z

296

Search for gravitational waves associated with the InterPlanetary Network short gamma ray bursts

We outline the scientific motivation behind a search for gravitational waves associated with short gamma ray bursts detected by the InterPlanetary Network (IPN) during LIGO's fifth science run and Virgo's first science run. The IPN localisation of short gamma ray bursts is limited to extended error boxes of different shapes and sizes and a search on these error boxes poses a series of challenges for data analysis. We will discuss these challenges and outline the methods to optimise the search over these error boxes.

V. Predoi; for the LIGO Scientific Collaboration; for the Virgo Collaboration; K. Hurley; for IPN

2011-12-07T23:59:59.000Z

297

The future laser interferometric gravitational-wave detectors' sensitivity can be improved using squeezed light. In particular, recently a scheme which uses the optical field with frequency-dependent squeeze factor, prepared by means of a relatively short ({approx}30 m) amplitude filter cavity, was proposed [Thomas Corbitt, Nergis Mavalvala, and Stan Whitcomb, Phys. Rev. D 70, 022002 (2004).]. Here we consider an improved version of this scheme, which allows one to further reduce the quantum noise by exploiting the quantum entanglement between the optical fields at the filter cavity two ports.

Khalili, F. Ya. [Physics Faculty, Moscow State University, Moscow 119992 (Russian Federation)

2008-03-15T23:59:59.000Z

298

LIGO and Virgo recently completed searches for gravitational waves at their initial target sensitivities, and soon Advanced LIGO and Advanced Virgo will commence observations with even better capabilities. In the search for short duration signals, such as coalescing compact binary inspirals or "burst" events, noise transients can be problematic. Interferometric gravitational-wave detectors are highly complex instruments, and, based on the experience from the past, the data often contain a large number of noise transients that are not easily distinguishable from possible gravitational-wave signals. In order to perform a sensitive search for short-duration gravitational-wave signals it is important to identify these noise artifacts, and to "veto" them. Here we describe such a veto, the bilinear-coupling veto, that makes use of an empirical model of the coupling of instrumental noise to the output strain channel of the interferometric gravitational-wave detector. In this method, we check whether the data from the output strain channel at the time of an apparent signal is consistent with the data from a bilinear combination of auxiliary channels. We discuss the results of the application of this veto on recent LIGO data, and its possible utility when used with data from Advanced LIGO and Advanced Virgo.

Parameswaran Ajith; Tomoki Isogai; Nelson Christensen; Rana Adhikari; Aaron B. Pearlman; Alex Wein; Alan J. Weinstein; Ben Yuan

2014-05-27T23:59:59.000Z

299

Mergers of two compact objects, like two neutron stars or a neutron star and a black hole, are the probable progenitor of short gamma-ray bursts. These events are also promising sources of gravitational waves, that are currently motivating related searches by an international network of gravitational wave detectors. Here we describe a search for gravitational waves from the in-spiral phase of two coalescing compact objects, in coincidence with short GRBs occurred during during LIGO's fifth science run and Virgo's first science run. The search includes 22 GRBs for which data from more than one of the detectors in the LIGO/Virgo network were available. No statistically significant gravitational-wave candidate has been found, and a parametric test shows no excess of weak gravitational-wave signals in our sample of GRBs. The 90\\%~C.L. median exclusion distance for GRBs in our sample is of 6.7 Mpc, under the hypothesis of a neutron star - black hole progenitor model.

Alexander Dietz

2010-06-17T23:59:59.000Z

300

We apply a machine learning algorithm, the artificial neural network, to the search for gravitational-wave signals associated with short gamma-ray bursts. The multi-dimensional samples consisting of data corresponding to the statistical and physical quantities from the coherent search pipeline are fed into the artificial neural network to distinguish simulated gravitational-wave signals from background noise artifacts. Our result shows that the data classification efficiency at a fixed false alarm probability is improved by the artificial neural network in comparison to the conventional detection statistic. Therefore, this algorithm increases the distance at which a gravitational-wave signal could be observed in coincidence with a gamma-ray burst. In order to demonstrate the performance, we also evaluate a few seconds of gravitational-wave data segment using the trained networks and obtain the false alarm probability. We suggest that the artificial neural network can be a complementary method to the conventional detection statistic for identifying gravitational-wave signals related to the short gamma-ray bursts.

Kyungmin Kim; Ian W. Harry; Kari A. Hodge; Young-Min Kim; Chang-Hwan Lee; Hyun Kyu Lee; John J. Oh; Sang Hoon Oh; Edwin J. Son

2015-03-03T23:59:59.000Z

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301

In an extended, new form of general relativity, which is a teleparallel theory of gravity, we examine the energy-momentum and angular momentum carried by gravitational wave radiated from Newtonian point masses in a weak-field approximation. The resulting wave form is identical to the corresponding wave form in general relativity, which is consistent with previous results in teleparallel theory. The expression for the dynamical energy-momentum density is identical to that for the canonical energy-momentum density in general relativity up to leading order terms on the boundary of a large sphere including the gravitational source, and the loss of dynamical energy-momentum, which is the generator of \\emph{internal} translations, is the same as that of the canonical energy-momentum in general relativity. Under certain asymptotic conditions for a non-dynamical Higgs-type field $\\psi^{k}$, the loss of ``spin'' angular momentum, which is the generator of \\emph{internal} $SL(2,C)$ transformations, is the same as that of angular momentum in general relativity, and the losses of canonical energy-momentum and orbital angular momentum, which constitute the generator of Poincar\\'{e} \\emph{coordinate} transformations, are vanishing. The results indicate that our definitions of the dynamical energy-momentum and angular momentum densities in this extended new general relativity work well for gravitational wave radiations, and the extended new general relativity accounts for the Hulse-Taylor measurement of the pulsar PSR1913+16.

Eisaku Sakane; Toshiharu Kawai

2002-09-30T23:59:59.000Z

302

The characterization of Virgo data and its impact on gravitational-wave searches

Between 2007 and 2010 Virgo collected data in coincidence with the LIGO and GEO gravitational-wave (GW) detectors. These data have been searched for GWs emitted by cataclysmic phenomena in the universe, by non-axisymmetric rotating neutron stars or from a stochastic background in the frequency band of the detectors. The sensitivity of GW searches is limited by noise produced by the detector or its environment. It is therefore crucial to characterize the various noise sources in a GW detector. This paper reviews the Virgo detector noise sources, noise propagation, and conversion mechanisms which were identified in the three first Virgo observing runs. In many cases, these investigations allowed us to mitigate noise sources in the detector, or to selectively flag noise events and discard them from the data. We present examples from the joint LIGO-GEO-Virgo GW searches to show how well noise transients and narrow spectral lines have been identified and excluded from the Virgo data. We also discuss how detector characterization can improve the astrophysical reach of gravitational-wave searches.

J. Aasi; J. Abadie; B. P. Abbott; R. Abbott; T. D. Abbott; M. Abernathy; T. Accadia; F. Acernese; C. Adams; T. Adams; P. Addesso; R. Adhikari; C. Affeldt; M. Agathos; K. Agatsuma; P. Ajith; B. Allen; A. Allocca; E. Amador Ceron; D. Amariutei; S. B. Anderson; W. G. Anderson; K. Arai; M. C. Araya; S. Ast; S. M. Aston; P. Astone; D. Atkinson; P. Aufmuth; C. Aulbert; B. E. Aylott; S. Babak; P. Baker; G. Ballardin; T. Ballinger; S. Ballmer; Y. Bao; J. C. B. Barayoga; D. Barker; F. Barone; B. Barr; L. Barsotti; M. Barsuglia; M. A. Barton; I. Bartos; R. Bassiri; M. Bastarrika; A. Basti; J. Batch; J. Bauchrowitz; Th. S. Bauer; M. Bebronne; D. Beck; B. Behnke; M. Bejger; M. G. Beker; A. S. Bell; C. Bell; I. Belopolski; M. Benacquista; J. M. Berliner; A. Bertolini; J. Betzwieser; N. Beveridge; P. T. Beyersdorf; T. Bhadbade; I. A. Bilenko; G. Billingsley; J. Birch; R. Biswas; M. Bitossi; M. A. Bizouard; E. Black; J. K. Blackburn; L. Blackburn; D. Blair; B. Bland; M. Blom; O. Bock; T. P. Bodiya; C. Bogan; C. Bond; R. Bondarescu; F. Bondu; L. Bonelli; R. Bonnand; R. Bork; M. Born; V. Boschi; S. Bose; L. Bosi; B. Bouhou; S. Braccini; C. Bradaschia; P. R. Brady; V. B. Braginsky; M. Branchesi; J. E. Brau; J. Breyer; T. Briant; D. O. Bridges; A. Brillet; M. Brinkmann; V. Brisson; M. Britzger; A. F. Brooks; D. A. Brown; T. Bulik; H. J. Bulten; A. Buonanno; J. Burguet--Castell; D. Buskulic; C. Buy; R. L. Byer; L. Cadonati; G. Cagnoli; G. Cagnoli; E. Calloni; J. B. Camp; P. Campsie; K. Cannon; B. Canuel; J. Cao; C. D. Capano; F. Carbognani; L. Carbone; S. Caride; S. Caudill; M. Cavagliŕ; F. Cavalier; R. Cavalieri; G. Cella; C. Cepeda; E. Cesarini; T. Chalermsongsak; P. Charlton; E. Chassande-Mottin; W. Chen; X. Chen; Y. Chen; A. Chincarini; A. Chiummo; H. S. Cho; J. Chow; N. Christensen; S. S. Y. Chua; C. T. Y. Chung; S. Chung; G. Ciani; F. Clara; D. E. Clark; J. A. Clark; J. H. Clayton; F. Cleva; E. Coccia; P. -F. Cohadon; C. N. Colacino; A. Colla; M. Colombini; A. Conte; R. Conte; D. Cook; T. R. Corbitt; M. Cordier; N. Cornish; A. Corsi; C. A. Costa; M. Coughlin; J. -P. Coulon; P. Couvares; D. M. Coward; M. Cowart; D. C. Coyne; J. D. E. Creighton; T. D. Creighton; A. M. Cruise; A. Cumming; L. Cunningham; E. Cuoco; R. M. Cutler; K. Dahl; M. Damjanic; S. L. Danilishin; S. D'Antonio; K. Danzmann; V. Dattilo; B. Daudert; H. Daveloza; M. Davier; E. J. Daw; R. Day; T. Dayanga; R. De Rosa; D. DeBra; G. Debreczeni; J. Degallaix; W. Del Pozzo; T. Dent; V. Dergachev; R. DeRosa; S. Dhurandhar; L. Di Fiore; A. Di Lieto; I. Di Palma; M. Di Paolo Emilio; A. Di Virgilio; M. Díaz; A. Dietz; A. Dietz; F. Donovan; K. L. Dooley; S. Doravari; S. Dorsher; M. Drago; R. W. P. Drever; J. C. Driggers; Z. Du; J. -C. Dumas; S. Dwyer; T. Eberle; M. Edgar; M. Edwards; A. Effler; P. Ehrens; G. Endr?czi; R. Engel; T. Etzel; K. Evans; M. Evans; T. Evans; M. Factourovich; V. Fafone; S. Fairhurst; B. F. Farr; M. Favata; D. Fazi; H. Fehrmann; D. Feldbaum; I. Ferrante; F. Ferrini; F. Fidecaro; L. S. Finn; I. Fiori; R. P. Fisher; R. Flaminio; S. Foley; E. Forsi; N. Fotopoulos; J. -D. Fournier; J. Franc; S. Franco; S. Frasca; F. Frasconi; M. Frede; M. A. Frei; Z. Frei; A. Freise; R. Frey; T. T. Fricke; D. Friedrich; P. Fritschel; V. V. Frolov; M. -K. Fujimoto; P. J. Fulda; M. Fyffe; J. Gair; M. Galimberti; L. Gammaitoni; J. Garcia; F. Garufi; M. E. Gáspár; G. Gelencser; G. Gemme; E. Genin; A. Gennai; L. Á. Gergely; S. Ghosh; J. A. Giaime; S. Giampanis; K. D. Giardina; A. Giazotto; S. Gil-Casanova; C. Gill; J. Gleason; E. Goetz; G. González; M. L. Gorodetsky; S. Goßler; R. Gouaty; C. Graef; P. B. Graff; M. Granata; A. Grant; C. Gray; R. J. S. Greenhalgh; A. M. Gretarsson; C. Griffo; H. Grote; K. Grover; S. Grunewald; G. M. Guidi; C. Guido; R. Gupta; E. K. Gustafson; R. Gustafson; J. M. Hallam; D. Hammer; G. Hammond; J. Hanks; C. Hanna; J. Hanson; A. Hardt; J. Harms; G. M. Harry; I. W. Harry; E. D. Harstad; M. T. Hartman; K. Haughian; K. Hayama; J. -F. Hayau; J. Heefner; A. Heidmann; M. C. Heintze; H. Heitmann; P. Hello; M. A. Hendry; I. S. Heng; A. W. Heptonstall; V. Herrera; M. Heurs; M. Hewitson; S. Hild; D. Hoak; K. A. Hodge; K. Holt; M. Holtrop; T. Hong; S. Hooper; J. Hough; E. J. Howell; B. Hughey; S. Husa; S. H. Huttner; T. Huynh-Dinh; D. R. Ingram; R. Inta; T. Isogai; A. Ivanov; K. Izumi; M. Jacobson; E. James; Y. J. Jang; P. Jaranowski; E. Jesse; W. W. Johnson; D. I. Jones; R. Jones; R. J. G. Jonker; L. Ju; P. Kalmus; V. Kalogera; S. Kandhasamy; G. Kang; J. B. Kanner; M. Kasprzack; R. Kasturi; E. Katsavounidis; W. Katzman; H. Kaufer; K. Kaufman; K. Kawabe; S. Kawamura; F. Kawazoe; D. Keitel; D. Kelley; W. Kells; D. G. Keppel; Z. Keresztes; A. Khalaidovski; F. Y. Khalili; E. A. Khazanov; B. K. Kim; C. Kim; H. Kim; K. Kim; N. Kim; Y. M. Kim; P. J. King; D. L. Kinzel; J. S. Kissel; S. Klimenko; J. Kline; K. Kokeyama; V. Kondrashov

2012-06-18T23:59:59.000Z

303

The cryogenic resonant gravitational wave detectors NAUTILUS and EXPLORER, made of an aluminum alloy bar, can detect cosmic ray showers. At temperatures above 1 K, when the material is in the normal conducting state, the measured signals are in good agreement with the values expected based on the cosmic rays data and on the thermo-acoustic model. When NAUTILUS was operated at the temperature of 0.14 K, in superconductive state, large signals produced by cosmic ray interactions, more energetic than expected, were recorded. The NAUTILUS data in this case are in agreement with the measurements done by a dedicated experiment on a particle beam. The biggest recorded event was in EXPLORER and excited the first longitudinal mode to a vibrational energy of about 670 K, corresponding to about 360 TeV absorbed in the bar. Cosmic rays can be an important background in future acoustic detectors of improved sensitivity. At present, they represent a useful tool to verify the gravitational wave antenna performance.

P. Astone; D. Babusci; M. Bassan; P. Bonifazi; G. Cavallari; E. Coccia; S. D'Antonio; V. Fafone; G. Giordano; C. Ligi; A. Marini; G. Mazzitelli; Y. Minenkov; I. Modena; G. Modestino; A. Moleti; G. V. Pallottino; G. Pizzella; L. Quintieri; A. Rocchi; F. Ronga; R. Terenzi; M. Visco

2008-06-14T23:59:59.000Z

304

Friction in Gravitational Waves: a test for early-time modified gravity

Modified gravity theories predict in general a non standard equation for the propagation of gravitational waves. Here we discuss the impact of modified friction and speed of tensor modes on cosmic microwave polarization B modes. We show that the non standard friction term, parametrized by $\\alpha_{M}$, is degenerate with the tensor-to-scalar ratio $r$, so that small values of $r$ can be compensated by negative constant values of $\\alpha_M$. We quantify this degeneracy and its dependence on the epoch at which $\\alpha_{M}$ is different from the standard, zero, value and on the speed of gravitational waves $c_{T}$. In the particular case of scalar-tensor theories, $\\alpha_{M}$ is constant and strongly constrained by background and scalar perturbations, $0\\le \\alpha_{M}< 0.01$ and the degeneracy with $r$ is removed. In more general cases however such tight bounds are weakened and the B modes can provide useful constraints on early-time modified gravity.

Valeria Pettorino; Luca Amendola

2014-08-10T23:59:59.000Z

305

Gravitational waves generated by inspiralling compact binaries are investigated to the second--post-Newtonian (2PN) approximation of general relativity. Using a recently developed 2PN-accurate wave generation formalism, we compute the gravitational waveform and associated energy loss rate from a binary system of point-masses moving on a quasi-circular orbit. The crucial new input is our computation of the 2PN-accurate ``source'' quadrupole moment of the binary. Tails in both the waveform and energy loss rate at infinity are explicitly computed. Gravitational radiation reaction effects on the orbital frequency and phase of the binary are deduced from the energy loss. In the limiting case of a very small mass ratio between the two bodies we recover the results obtained by black hole perturbation methods. We find that finite mass ratio effects are very significant as they increase the 2PN contribution to the phase by up to 52\\%. The results of this paper should be of use when deciphering the signals observed by the future LIGO/VIRGO network of gravitational-wave detectors.

Luc Blanchet; Thibault Damour; Bala R. Iyer

1995-01-24T23:59:59.000Z

306

Compact binary coalescences are a promising source of gravitational waves for second-generation interferometric gravitational-wave detectors such as advanced LIGO and advanced Virgo. While most binaries are expected to possess circular orbits, some may be eccentric, for example, if they are formed through dynamical capture. Eccentric orbits can create difficulty for matched filtering searches due to the challenges of creating effective template banks to detect these signals. In previous work, we showed how seedless clustering can be used to detect low-mass ($M_\\text{total}\\leq10M_\\odot$) compact binary coalescences for both spinning and eccentric systems, assuming a circular post-Newtonian expansion. Here, we describe a parameterization that is designed to maximize sensitivity to low-eccentricity ($0\\leq\\epsilon\\leq0.6$) systems, derived from the analytic equations. We show that this parameterization provides a robust and computationally efficient method for detecting eccentric low-mass compact binaries. Based on these results, we conclude that advanced detectors will have a chance of detecting eccentric binaries if optimistic models prove true. However, a null observation is unlikely to firmly rule out models of eccentric binary populations.

Michael Coughlin; Patrick Meyers; Eric Thrane; Jialun Luo; Nelson Christensen

2014-12-19T23:59:59.000Z

307

Correlated noise in networks of gravitational-wave detectors: subtraction and mitigation

One of the key science goals of advanced gravitational-wave detectors is to observe a stochastic gravitational-wave background. However, recent work demonstrates that correlated magnetic fields from Schumann resonances can produce correlated strain noise over global distances, potentially limiting the sensitivity of stochastic background searches with advanced detectors. In this paper, we estimate the correlated noise budget for the worldwide Advanced LIGO network and conclude that correlated noise may affect upcoming measurements. We investigate the possibility of a Wiener filtering scheme to subtract correlated noise from Advanced LIGO searches, and estimate the required specifications. We also consider the possibility that residual correlated noise remains following subtraction, and we devise an optimal strategy for measuring astronomical parameters in the presence of correlated noise. Using this new formalism, we estimate the loss of sensitivity for a broadband, isotropic stochastic background search using 1 yr of LIGO data at design sensitivity. Given our current noise budget, the uncertainty with which LIGO can estimate energy density will likely increase by a factor of ~4--if it is impossible to achieve significant subtraction. Additionally, narrowband cross-correlation searches may be severely affected at low frequencies f < 45 Hz without effective subtraction.

Eric Thrane; Nelson Christensen; Robert M. S. Schofield; Anamaria Effler

2014-06-23T23:59:59.000Z

308

Introduction to the Analysis of Low-Frequency Gravitational Wave Data

The space-based gravitational wave detector LISA will observe in the low-frequency gravitational-wave band (0.1 mHz up to 1 Hz). LISA will search for a variety of expected signals, and when it detects a signal it will have to determine a number of parameters, such as the location of the source on the sky and the signal's polarisation. This requires pattern-matching, called matched filtering, which uses the best available theoretical predictions about the characteristics of waveforms. All the estimates of the sensitivity of LISA to various sources assume that the data analysis is done in the optimum way. Because these techniques are unfamiliar to many young physicists, I use the first part of this lecture to give a very basic introduction to time-series data analysis, including matched filtering. The second part of the lecture applies these techniques to LISA, showing how estimates of LISA's sensitivity can be made, and briefly commenting on aspects of the signal-analysis problem that are special to LISA.

B. F. Schutz

1997-10-15T23:59:59.000Z

309

The parallelization, design and scalability of the \\sky code to search for periodic gravitational waves from rotating neutron stars is discussed. The code is based on an efficient implementation of the F-statistic using the Fast Fourier Transform algorithm. To perform an analysis of data from the advanced LIGO and Virgo gravitational wave detectors' network, which will start operating in 2015, hundreds of millions of CPU hours will be required - the code utilizing the potential of massively parallel supercomputers is therefore mandatory. We have parallelized the code using the Message Passing Interface standard, implemented a mechanism for combining the searches at different sky-positions and frequency bands into one extremely scalable program. The parallel I/O interface is used to escape bottlenecks, when writing the generated data into file system. This allowed to develop a highly scalable computation code, which would enable the data analysis at large scales on acceptable time scales. Benchmarking of the code on a Cray XE6 system was performed to show efficiency of our parallelization concept and to demonstrate scaling up to 50 thousand cores in parallel.

Gevorg Poghosyan; Sanchit Matta; Achim Streit; Micha? Bejger; Andrzej Królak

2014-10-14T23:59:59.000Z

310

Detecting very long-lived gravitational-wave transients lasting hours to weeks

We explore the possibility of very long-lived gravitational-wave transients (and detector artifacts) lasting hours to weeks. Such very long signals are both interesting in their own right and as a potential source of systematic error in searches for persistent signals, e.g., from a stochastic gravitational-wave background. We review possible mechanisms for emission on these time scales and discuss computational challenges associated with their detection: namely, the substantial volume of data involved in a search for very long transients can require vast computer memory and processing time. These computational difficulties can be addressed through a form of data compression known as coarse-graining, in which information about short time spans is discarded in order to reduce the computational requirements of a search. Using data compression, we demonstrate an efficient radiometer (cross-correlation) algorithm for the detection of very long transients. In the process, we identify features of a very long transient search (related to the rotation of the Earth) that make it more complicated than a search for shorter transient signals. We implement suitable solutions.

Eric Thrane; Vuk Mandic; Nelson Christensen

2015-01-27T23:59:59.000Z

311

Bayesian parameter estimation of core collapse supernovae using gravitational wave simulations

Using the latest numerical simulations of rotating stellar core collapse, we present a Bayesian framework to extract the physical information encoded in noisy gravitational wave signals. We fit Bayesian principal component regression models with known and unknown signal arrival times to reconstruct gravitational wave signals, and subsequently fit known astrophysical parameters on the posterior means of the principal component coefficients using a linear model. We predict the ratio of rotational kinetic energy to gravitational energy of the inner core at bounce by sampling from the posterior predictive distribution, and find that these predictions are generally very close to the true parameter values, with $90\\%$ credible intervals $\\sim 0.04$ and $\\sim 0.06$ wide for the known and unknown arrival time models respectively. Two supervised machine learning methods are implemented to classify precollapse differential rotation, and we find that these methods discriminate rapidly rotating progenitors particularly well. We also introduce a constrained optimization approach to model selection to find an optimal number of principal components in the signal reconstruction step. Using this approach, we select 14 principal components as the most parsimonious model.

Matthew C. Edwards; Renate Meyer; Nelson Christensen

2014-07-28T23:59:59.000Z

312

Use of gravitational waves to measure alignment of spins in compact binaries

Coalescences of compact objects, neutron star and black holes, in binary systems are very promising sources of gravitational waves for the ground based detectors Advanced LIGO and Virgo. Much about compact binaries is still uncertain, including how often they are formed in the Universe, and some key details about their formation channels. One of the key open questions about compact binary coalescences is whether or not common envelope evolution is highly efficient in aligning spins with the orbital angular momentum. In this paper we show how gravitational waves detected by Advanced LIGO and Virgo can be used to verify if spins are preferentially aligned with the orbital angular momentum in compact binaries made of two black holes or a neutron star and a black hole. We first assume that all sources have either nearly aligned or non-aligned spins and use Bayesian model selection to calculate a cumulative odds ratio to compare the aligned and non-aligned models. We see that the correct model is typically preferr...

Vitale, Salvatore; Graff, Philip; Sturani, Riccardo

2015-01-01T23:59:59.000Z

313

Gravitational Wave Background from Neutrino-Driven Gamma-Ray Bursts

We discuss the gravitational wave background (GWB) from a cosmological population of gamma-ray bursts (GRBs). Among various emission mechanisms for the gravitational waves (GWs), we pay a particular attention to the vast anisotropic neutrino emissions from the accretion disk around the black hole formed after the so-called failed supernova explosions. The produced GWs by such mechanism are known as burst with memory, which could dominate over the low-frequency regime below \\sim 10Hz. To estimate their amplitudes, we derive general analytic formulae for gravitational waveform from the axisymmetric jets. Based on the formulae, we first quantify the spectrum of GWs from a single GRB. Then, summing up its cosmological population, we find that the resultant value of the density parameter becomes roughly \\Omega_{GW} \\approx 10^{-20} over the wide-band of the low-frequency region, f\\sim 10^{-4}-10^1Hz. The amplitude of GWB is sufficiently smaller than the primordial GWBs originated from an inflationary epoch and far below the detection limit.

Takashi Hiramatsu; Kei Kotake; Hideaki Kudoh; Atsushi Taruya

2005-09-27T23:59:59.000Z

314

A WASHINGTON STATE UNIVERSITY POSTDOCTORAL POSITION FOR WORK AT LIGO HANFORD, WA Applications characterization for the Advanced Laser Interferometer Gravitational wave Observatory (LIGO) at the Hanford site characterization at the LIGO Hanford observatory. Familiarity with data analysis pipelines for searching

Collins, Gary S.

315

Inelastic back-scattering of stray light is a long-standing problem in high-sensitivity interferometric measurements and a potential limitation for advanced gravitational-wave detectors, in particular at sub-audio-band frequencies. The emerging parasitic interferences cannot be distinguished from a scientific signal via conventional single readout. In this work, we propose and demonstrate the subtraction of inelastic back-scatter signals by employing dual homodyne detection on the output light -- here -- of a table-top Michelson interferometer. The additional readout contains solely parasitic signals and is used to model the scatter source. Subtraction of the scatter signal reduces the noise spectral density and thus improves the measurement sensitivity. Our scheme is qualitatively different from the previously demonstrated vetoing of scatter signals and opens a new path for improving the sensitivity of future gravitational-wave detectors.

Meinders, Melanie

2015-01-01T23:59:59.000Z

316

Gravitational waves (GWs) are one of the key signatures of cosmic strings. If GWs from cosmic strings are detected in future experiments, not only their existence can be confirmed but also their properties might be probed. In this paper, we study the determination of cosmic string parameters through direct detection of GW signatures in future ground-based GW experiments. We consider two types of GWs, bursts and the stochastic GW background, which provide us with different information about cosmic string properties. Performing the Fisher matrix calculation on the cosmic string parameters, such as parameters governing the string tension $G\\mu$ and initial loop size $\\alpha$ and the reconnection probability $p$, we find that the two different types of GW can break degeneracies in some of these parameters and provide better constraints than those from each measurement.

Sachiko Kuroyanagi; Koichi Miyamoto; Toyokazu Sekiguchi; Keitaro Takahashi; Joseph Silk

2012-06-25T23:59:59.000Z

317

We study how direct detection of the inflationary gravitational wave background constrains inflationary parameters and complements CMB polarization measurements. The error ellipsoids calculated using the Fisher information matrix approach with Planck and the direct detection experiment, BBO (Big Bang Observer), show different directions of parameter degeneracy, and the degeneracy is broken when they are combined. For a slow-roll parameterization, we show that BBO could significantly improve the constraints on the tensor-to-scalar ratio compared with Planck alone. We also look at a quadratic and a natural inflation model. In both cases, if the temperature of reheating is also treated as a free parameter, then the addition of BBO can significantly improve the error bars. In the case of natural inflation, we find that the addition of BBO could even partially improve the error bars of a cosmic variance-limited CMB experiment.

Sachiko Kuroyanagi; Christopher Gordon; Joseph Silk; Naoshi Sugiyama

2010-08-02T23:59:59.000Z

318

Interpretation of the Siklos solutions as exact gravitational waves in the anti-de Sitter universe

The Siklos class of solutions of Einstein's field equations is investigated by analytical methods. By studying the behaviour of free particles we reach the conclusion that the space-times represent exact gravitational waves propagating in the anti-de Sitter universe. The presence of a negative cosmological constant implies that the 'background' space is not asymptotically flat and requires a 'rotating' reference frames in order to fully simplify and view the behaviour of nearby test particles. The Kaigorodov space-time, which is the simplest representative of the Siklos class, is analyzed in more detail. It is argued that it may serve as a 'cosmological' analogue of the well-known homogeneous pp-waves in the flat universe.

J. Podolsky

1998-01-15T23:59:59.000Z

319

The interaction of a gravitational wave with a system made of an RLC circuit forming one end of a mechanical harmonic oscillator is investigated. We show that, in some configurations, the coherent interaction of the wave with both the mechanical oscillator and the RLC circuit gives rise to a mechanical quality factor increase of the electromagnetic signal. When this system is used as an amplifier of gravitational periodic signals in the frequency range 50-1000 Hz, at ultracryogenic temperatures and for sufficiently long integration times (up to 4 months), a sensitivity of 10^(-24)-10^(-27) on the amplitude of the metric could be achieved when thermal noise, shot noise and amplifier back--action are considered.

Enrico Montanari; Pierluigi Fortini

1998-08-26T23:59:59.000Z

320

Parameter-space correlations of the optimal statistic for continuous gravitational-wave detection

The phase parameters of matched-filtering searches for continuous gravitational-wave signals are sky position, frequency and frequency time-derivatives. The space of these parameters features strong global correlations in the optimal detection statistic. For observation times smaller than one year, the orbital motion of the Earth leads to a family of global-correlation equations which describes the "global maximum structure" of the detection statistic. The solution to each of these equations is a different hypersurface in parameter space. The expected detection statistic is maximal at the intersection of these hypersurfaces. The global maximum structure of the detection statistic from stationary instrumental-noise artifacts is also described by the global-correlation equations. This permits the construction of a veto method which excludes false candidate events.

Holger J. Pletsch

2009-05-19T23:59:59.000Z

While these samples are representative of the content of NLE

they are not comprehensive nor are they the most current set.

We encourage you to perform a real-time search of NLE

to obtain the most current and comprehensive results.

321

We provide calculations and theoretical arguments supporting the emission of electromagnetic radiation from charged particles accelerated by gravitational waves (GWs). These waves have significant indirect evidence to support their existence, yet they interact weakly with ordinary matter. We show that the induced oscillations of charged particles interacting with a GW, which lead to the emission of electromagnetic radiation, will also result in wave attenuation. These ideas are supported by a small body of literature, as well as additional arguments for particle acceleration based on GW memory effects. We derive order of magnitude power calculations for various initial charge distributions accelerated by GWs. The resulting power emission is extremely small for all but very strong GWs interacting with large quantities of charge. If the results here are confirmed and supplemented, significant consequences such as attenuation of early universe GWs could result. Additionally, this effect could extend GW detection...

Revalski, Mitchell; Wickramasinghe, Thulsi

2015-01-01T23:59:59.000Z

322

It is shown that coupling system between fractal membranes and a Gaussian beam passing through a static magnetic field has strong selection capability for the stochastic relic gravitational wave background. The relic GW components propagating along the positive direction of the symmetrical axis of the Gaussian beam might generate an optimal electromagnetic perturbation while the perturbation produced by the relic GW components propagating along the negative and perpendicular directions to the symmetrical axis will be much less than the former.The influence of the random fluctuation of the relic GWs to such effect can be neglected and the influence of the random fluctuation of the relic GWs to such effect can be neglected.

Fangyu Li; Zhenya Chen; Ying Yi

2005-11-03T23:59:59.000Z

323

Interaction of a charged particle in a static magnetic background, i.e., a Landau system with circularly polarised gravitational wave (GW) is studied quantum mechanically in the long wavelength and low velocity limit. We quantize the classical Hamiltonian following \\cite{speli}. The rotating polarization vectors of the circularly polarized GW are employed to form a unique directional triad which served as the coordinate axes. The Schrodinger equations for the system are cast in the form of a set of coupled linear differential equations. This system is solved by iterative technique. We compute the time-evolution of the position and momentum expectation values of the particle. The results show that the resonance behaviour obtained earlier\\cite{emgw_classical} by classical treatements of the system has a quantum analogue not only for the linearly polarized GW \\cite{emgw_1_lin}, but for circularly polarized GW as well.

Sunandan Gangopadhyay; Anirban Saha; Swarup Saha

2014-12-24T23:59:59.000Z

324

An upper bound from helioseismology on the stochastic background of gravitational waves

The universe is expected to be permeated by a stochastic background of gravitational radiation of astrophysical and cosmological origin. This background is capable of exciting oscillations in solar-like stars. Here we show that solar-like oscillators can be employed as giant hydrodynamical detectors for such a background in the muHz to mHz frequency range, which has remained essentially unexplored until today. We demonstrate this approach by using high-precision radial velocity data for the Sun to constrain the normalized energy density of the stochastic gravitational-wave background around 0.11 mHz. These results open up the possibility for asteroseismic missions like CoRoT and Kepler to probe fundamental physics.

Daniel M. Siegel; Markus Roth

2014-03-28T23:59:59.000Z

325

Gravitational waves from the sound of a first order phase transition

We report on the first 3-dimensional numerical simulations of first-order phase transitions in the early universe to include the cosmic fluid as well as the scalar field order parameter. We calculate the gravitational wave (GW) spectrum resulting from the nucleation, expansion and collision of bubbles of the low-temperature phase, for phase transition strengths and bubble wall velocities covering many cases of interest. We find that the compression waves in the fluid continue to be a source of GWs long after the bubbles have merged, a new effect not taken properly into account in previous modelling of the GW source. For a wide range of models the main source of the GWs produced by a phase transition is therefore the sound the bubbles make.

Mark Hindmarsh; Stephan J. Huber; Kari Rummukainen; David J. Weir

2014-01-29T23:59:59.000Z

326

In low-energy effective string theory and modified gravity theories, the propagating speed $c_T$ of primordial gravitational waves may deviate from unity. We find that the step-like variation of $c_T$ during slow-roll inflation may result in an oscillating modulation to the B-mode polarization spectrum, which can hardly be imitated by adjusting other cosmological parameters, and the intensity of the modulation is determined by the dynamics of $c_T$. Thus provided that the foreground contribution is under control, high-precision CMB polarization observations will be able to put tight constraint on the variation of $c_T$, and so the corresponding theories.

Cai, Yong; Piao, Yun-Song

2015-01-01T23:59:59.000Z

327

Search for periodic gravitational radiation with the ALLEGRO gravitational wave detector

We describe the search for a continuous signal of gravitational radiation from a rotating neutron star in the data taken by the ALLEGRO gravitational wave detector in early 1994. Since ALLEGRO is sensitive at frequencies near 1 kHz, only neutron stars with spin periods near 2 ms are potential sources. There are no known sources of this typ e for ALLEGRO, so we directed the search towards both the galactic center and the globular clus ter 47 Tucanae. The analysis puts a constraint of roughly $8 \\times 10^{-24}$ at frequencies near 1 kHz on the gravitational strain emitted from pulsar spin-down in either 47 Tucanae or the galactic center.

E. Mauceli; M. P. McHugh; W. O. Hamilton; W. W. Johnson; A. Morse

2000-07-11T23:59:59.000Z

328

Search for periodic gravitational radiation with the ALLEGRO gravitational wave detector

We describe the search for a continuous signal of gravitational radiation from a rotating neutron star in the data taken by the ALLEGRO gravitational wave detector in early 1994. Since ALLEGRO is sensitive at frequencies near 1 kHz, only neutron stars with spin periods near 2 ms are potential sources. There are no known sources of this typ e for ALLEGRO, so we directed the search towards both the galactic center and the globular clus ter 47 Tucanae. The analysis puts a constraint of roughly $8 \\times 10^{-24}$ at frequencies near 1 kHz on the gravitational strain emitted from pulsar spin-down in either 47 Tucanae or the galactic center.

Mauceli, E; Hamilton, W O; Johnson, W W; Morse, A

2002-01-01T23:59:59.000Z

329

Comparison of Signals from Gravitational Wave Detectors with Instantaneous Time-Frequency Maps

Gravitational wave astronomy relies on the use of multiple detectors, so that coincident detections may distinguish real signals from instrumental artifacts, and also so that relative timing of signals can provide the sky position of sources. We show that the comparison of instantaneous time-frequency and time- amplitude maps provided by the Hilbert-Huang Transform (HHT) can be used effectively for relative signal timing of common signals, to discriminate between the case of identical coincident signals and random noise coincidences, and to provide a classification of signals based on their time-frequency trajectories. The comparison is done with a chi-square goodness-of-fit method which includes contributions from both the instantaneous amplitude and frequency components of the HHT to match two signals in the time domain. This approach naturally allows the analysis of waveforms with strong frequency modulation.

Alexander Stroeer; Lindy Blackburn; Jordan Camp

2011-05-24T23:59:59.000Z

330

How Gravitational-wave Observations Can Shape the Gamma-ray Burst Paradigm

By reaching through shrouding blastwaves, efficiently discovering off-axis events, and probing the central engine at work, gravitational wave (GW) observations will soon revolutionize the study of gamma-ray bursts. Already, analyses of GW data targeting gamma-ray bursts have helped constrain the central engines of selected events. Advanced GW detectors with significantly improved sensitivities are under construction. After outlining the GW emission mechanisms from gamma-ray burst progenitors (binary coalescences, stellar core collapses, magnetars, and others) that may be detectable with advanced detectors, we review how GWs will improve our understanding of gamma-ray burst central engines, their astrophysical formation channels, and the prospects and methods for different search strategies. We place special emphasis on multimessenger searches. To achieve the most scientific benefit, GW, electromagnetic, and neutrino observations should be combined to provide greater discriminating power and science reach.

Imre Bartos; Patrick Brady; Szabolcs Marka

2012-12-11T23:59:59.000Z

331

Primordial gravitational wave of BICEP2 from dynamical double hybrid inflation

BICEP2 has observed a primordial gravitational wave corresponding to the tensor-to-scalar ratio of 0.16. It seems to require a super-Planckian inflationary model. In this paper, we propose a double hybrid inflation model, where the inflaton potential dynamically changes with the evolution of the inflaton fields. During the first phase of inflation over 7 e-folds, the power spectrum can be almost constant by a large linear term in the hybrid potential, which is responsible also for the large tensor-to-scalar ratio. In the second phase of 50 e-folds, the dominant potential becomes dynamically changed to the logarithmic form as in the ordinary supersymmetric hybrid inflation, which is performed by the second inflaton field. In this model, the sub-Planckian field values (~0.9 M_P) can still yield the correct cosmic observations with the sufficient e-folds.

Ki-Young Choi; Bumseok Kyae

2014-06-30T23:59:59.000Z

332

The Role of Energy and a New Approach to Gravitational Waves in General Relativity

The energy localization hypothesis of the author that energy is localized in non-vanishing regions of the energy-momentum tensor implies that gravitational waves do not carry energy in vacuum. If substantiated, this has significant implications for current research. Support for the hypothesis is provided by a re-examination of Eddington's classic calculation of energy loss by a spinning rod. It is emphasized that Eddington did not monitor the entire Tolman energy integral, concentrating solely upon the change of the 'kinetic' part of the energy . The 'quadrupole formula' is thus seen to measure the kinetic energy change. When the derivative of the missing stress-trace integral is computed, it is seen to cancel the Eddington term and hence the energy of the rod is conserved, in support of the localization hypothesis. The issue of initial and final states is addressed.

F. I. Cooperstock

1999-04-19T23:59:59.000Z

333

Supermassive black holes or boson stars? Hair counting with gravitational wave detectors

The evidence for supermassive Kerr black holes in galactic centers is strong and growing, but only the detection of gravitational waves will convincingly rule out other possibilities to explain the observations. The Kerr spacetime is completely specified by the first two multipole moments: mass and angular momentum. This is usually referred to as the ``no-hair theorem'', but it is really a ``two-hair'' theorem. If general relativity is the correct theory of gravity, the most plausible alternative to a supermassive Kerr black hole is a rotating boson star. Numerical calculations indicate that the spacetime of rotating boson stars is determined by the first three multipole moments (``three-hair theorem''). LISA could accurately measure the oscillation frequencies of these supermassive objects. We propose to use these measurements to ``count their hair'', unambiguously determining their nature and properties.

Emanuele Berti; Vitor Cardoso

2006-05-17T23:59:59.000Z

334

Since gravitational wave spacetimes are time-varying vacuum solutions of Einstein's field equations, there is no unambiguous means to define their energy content. However, Weber and Wheeler had demonstrated that they do impart energy to test particles. There have been various proposals to define the energy content but they have not met with great success. Here we propose a definition using "slightly broken" Noether symmetries. We check whether this definition is physically acceptable. The procedure adopted is to appeal to "approximate symmetries" as defined in Lie analysis and use them in the limit of the exact symmetry holding. A problem is noted with the use of the proposal for plane-fronted gravitational waves. To attain a better understanding of the implications of this proposal we also use an artificially constructed time-varying non-vacuum metric and evaluate its Weyl and stress-energy tensors so as to obtain the gravitational and matter components separately and compare them with the energy content obtained by our proposal. The procedure is also used for cylindrical gravitational wave solutions. The usefulness of the definition is demonstrated by the fact that it leads to a result on whether gravitational waves suffer self-damping.

Ibrar Hussain; F. M. Mahomed; Asghar Qadir

2009-03-11T23:59:59.000Z

335

All-sky search for gravitational-wave bursts in the second joint LIGO-Virgo run

We present results from a search for gravitational-wave bursts in the data collected by the LIGO and Virgo detectors between July 7, 2009 and October 20, 2010: data are analyzed when at least two of the three LIGO-Virgo detectors are in coincident operation, with a total observation time of 207 days. The analysis searches for transients of duration < 1 s over the frequency band 64-5000 Hz, without other assumptions on the signal waveform, polarization, direction or occurrence time. All identified events are consistent with the expected accidental background. We set frequentist upper limits on the rate of gravitational-wave bursts by combining this search with the previous LIGO-Virgo search on the data collected between November 2005 and October 2007. The upper limit on the rate of strong gravitational-wave bursts at the Earth is 1.3 events per year at 90% confidence. We also present upper limits on source rate density per year and Mpc^3 for sample populations of standard-candle sources. As in the previous joint run, typical sensitivities of the search in terms of the root-sum-squared strain amplitude for these waveforms lie in the range 5 10^-22 Hz^-1/2 to 1 10^-20 Hz^-1/2. The combination of the two joint runs entails the most sensitive all-sky search for generic gravitational-wave bursts and synthesizes the results achieved by the initial generation of interferometric detectors.

the LIGO Scientific Collaboration; the Virgo Collaboration; J. Abadie; B. P. Abbott; R. Abbott; T. D. Abbott; M. Abernathy; T. Accadia; F. Acernese; C. Adams; R. Adhikari; C. Affeldt; M. Agathos; K. Agatsuma; P. Ajith; B. Allen; E. Amador Ceron; D. Amariutei; S. B. Anderson; W. G. Anderson; K. Arai; M. A. Arain; M. C. Araya; S. M. Aston; P. Astone; D. Atkinson; P. Aufmuth; C. Aulbert; B. E. Aylott; S. Babak; P. Baker; G. Ballardin; S. Ballmer; J. C. B. Barayoga; D. Barker; F. Barone; B. Barr; L. Barsotti; M. Barsuglia; M. A. Barton; I. Bartos; R. Bassiri; M. Bastarrika; A. Basti; J. Batch; J. Bauchrowitz; Th. S. Bauer; M. Bebronne; D. Beck; B. Behnke; M. Bejger; M. G. Beker; A. S. Bell; A. Belletoile; I. Belopolski; M. Benacquista; J. M. Berliner; A. Bertolini; J. Betzwieser; N. Beveridge; P. T. Beyersdorf; I. A. Bilenko; G. Billingsley; J. Birch; R. Biswas; M. Bitossi; M. A. Bizouard; E. Black; J. K. Blackburn; L. Blackburn; D. Blair; B. Bland; M. Blom; O. Bock; T. P. Bodiya; C. Bogan; R. Bondarescu; F. Bondu; L. Bonelli; R. Bonnand; R. Bork; M. Born; V. Boschi; S. Bose; L. Bosi; B. Bouhou; S. Braccini; C. Bradaschia; P. R. Brady; V. B. Braginsky; M. Branchesi; J. E. Brau; J. Breyer; T. Briant; D. O. Bridges; A. Brillet; M. Brinkmann; V. Brisson; M. Britzger; A. F. Brooks; D. A. Brown; T. Bulik; H. J. Bulten; A. Buonanno; J. Burguet-Castell; D. Buskulic; C. Buy; R. L. Byer; L. Cadonati; G. Cagnoli; E. Calloni; J. B. Camp; P. Campsie; J. Cannizzo; K. Cannon; B. Canuel; J. Cao; C. D. Capano; F. Carbognani; L. Carbone; S. Caride; S. Caudill; M. Cavaglia; F. Cavalier; R. Cavalieri; G. Cella; C. Cepeda; E. Cesarini; O. Chaibi; T. Chalermsongsak; P. Charlton; E. Chassande-Mottin; S. Chelkowski; W. Chen; X. Chen; Y. Chen; A. Chincarini; A. Chiummo; H. Cho; J. Chow; N. Christensen; S. S. Y. Chua; C. T. Y. Chung; S. Chung; G. Ciani; D. E. Clark; J. Clark; J. H. Clayton; F. Cleva; E. Coccia; P. -F. Cohadon; C. N. Colacino; J. Colas; A. Colla; M. Colombini; A. Conte; R. Conte; D. Cook; T. R. Corbitt; M. Cordier; N. Cornish; A. Corsi; C. A. Costa; M. Coughlin; J. -P. Coulon; P. Couvares; D. M. Coward; M. Cowart; D. C. Coyne; J. D. E. Creighton; T. D. Creighton; A. M. Cruise; A. Cumming; L. Cunningham; E. Cuoco; R. M. Cutler; K. Dahl; S. L. Danilishin; R. Dannenberg; S. D'Antonio; K. Danzmann; V. Dattilo; B. Daudert; H. Daveloza; M. Davier; E. J. Daw; R. Day; T. Dayanga; R. De Rosa; D. DeBra; G. Debreczeni; W. Del Pozzo; M. del Prete; T. Dent; V. Dergachev; R. DeRosa; R. DeSalvo; S. Dhurandhar; L. Di Fiore; A. Di Lieto; I. Di Palma; M. Di Paolo Emilio; A. Di Virgilio; M. Diaz; A. Dietz; F. Donovan; K. L. Dooley; M. Drago; R. W. P. Drever; J. C. Driggers; Z. Du; J. -C. Dumas; T. Eberle; M. Edgar; M. Edwards; A. Effler; P. Ehrens; G. Endroczi; R. Engel; T. Etzel; K. Evans; M. Evans; T. Evans; M. Factourovich; V. Fafone; S. Fairhurst; Y. Fan; B. F. Farr; D. Fazi; H. Fehrmann; D. Feldbaum; F. Feroz; I. Ferrante; F. Fidecaro; L. S. Finn; I. Fiori; R. P. Fisher; R. Flaminio; M. Flanigan; S. Foley; E. Forsi; L. A. Forte; N. Fotopoulos; J. -D. Fournier; J. Franc; S. Frasca; F. Frasconi; M. Frede; M. Frei; Z. Frei; A. Freise; R. Frey; T. T. Fricke; D. Friedrich; P. Fritschel; V. V. Frolov; M. -K. Fujimoto; P. J. Fulda; M. Fyffe; J. Gair; M. Galimberti; L. Gammaitoni; J. Garcia; F. Garufi; M. E. Gaspar; G. Gemme; R. Geng; E. Genin; A. Gennai; L. A. Gergely; S. Ghosh; J. A. Giaime; S. Giampanis; K. D. Giardina; A. Giazotto; S. Gil; C. Gill; J. Gleason; E. Goetz; L. M. Goggin; G. Gonzalez; M. L. Gorodetsky; S. Gossler; R. Gouaty; C. Graef; P. B. Graff; M. Granata; A. Grant; S. Gras; C. Gray; N. Gray; R. J. S. Greenhalgh; A. M. Gretarsson; C. Greverie; R. Grosso; H. Grote; S. Grunewald; G. M. Guidi; R. Gupta; E. K. Gustafson; R. Gustafson; T. Ha; J. M. Hallam; D. Hammer; G. Hammond; J. Hanks; C. Hanna; J. Hanson; A. Hardt; J. Harms; G. M. Harry; I. W. Harry; E. D. Harstad; M. T. Hartman; K. Haughian; K. Hayama; J. -F. Hayau; J. Heefner; A. Heidmann; M. C. Heintze; H. Heitmann; P. Hello; M. A. Hendry; I. S. Heng; A. W. Heptonstall; V. Herrera; M. Hewitson; S. Hild; D. Hoak; K. A. Hodge; K. Holt; M. Holtrop; T. Hong; S. Hooper; D. J. Hosken; J. Hough; E. J. Howell; B. Hughey; S. Husa; S. H. Huttner; R. Inta; T. Isogai; A. Ivanov; K. Izumi; M. Jacobson; E. James; Y. J. Jang; P. Jaranowski; E. Jesse; W. W. Johnson; D. I. Jones; G. Jones; R. Jones; L. Ju; P. Kalmus; V. Kalogera; S. Kandhasamy; G. Kang; J. B. Kanner; R. Kasturi; E. Katsavounidis; W. Katzman; H. Kaufer; K. Kawabe; S. Kawamura; F. Kawazoe; D. Kelley; W. Kells; D. G. Keppel; Z. Keresztes; A. Khalaidovski; F. Y. Khalili; E. A. Khazanov; B. Kim; C. Kim; H. Kim; K. Kim; N. Kim; Y. -M. Kim; P. J. King; D. L. Kinzel; J. S. Kissel; S. Klimenko; K. Kokeyama; V. Kondrashov; S. Koranda; W. Z. Korth; I. Kowalska; D. Kozak; O. Kranz; V. Kringel; S. Krishnamurthy

2012-04-20T23:59:59.000Z

336

We present an all-sky search for gravitational waves in the frequency range 1 to 6 kHz during the first calendar year of LIGO’s fifth science run. This is the first untriggered LIGO burst analysis to be conducted above 3 ...

Zucker, Michael E.

337

We study the thermal noise caused by mechanical or thermomechanical dissipation in mirrors of interferometric gravitational wave antennas. We give relative figures of merit for arbitrary Hermite-Gauss or Laguerre-Gauss optical beams regarding the Brownian and thermoelastic noises (substrate and coating) in the infinite mirror approximation.

Vinet, Jean-Yves [Dpt. ARTEMIS, Universite de Nice-Sophia Antipolis, C.N.R.S. and Observatoire de la Cote d'Azur, 06304 Nice (France)

2010-08-15T23:59:59.000Z

338

This brief report describes the search for gravitational-wave inspiral signals from short gamma-ray bursts. Since these events are probably created by the merger of two compact objects, a targeted search with a lower threshold can be made. The data around 22 short gamma-ray bursts have been analyzed.

Alexander Dietz

2010-06-16T23:59:59.000Z

339

beam needs to be phase locked to the cavity transmission to maintain correct phase to destructively to exciting new physics phenomena and techniques that may have application beyond gravitational wave detectors an optical cavity with an inside mechanical resonator has been frequency locked to the laser and 3-mode

Tobar, Michael

340

The Numerical INJection Analysis (NINJA) project is a collaborative effort between members of the numerical relativity and gravitational-wave data analysis communities. The purpose of NINJA is to study the sensitivity of existing gravitational-wave search algorithms using numerically generated waveforms and to foster closer collaboration between the numerical relativity and data analysis communities. We describe the results of the first NINJA analysis which focused on gravitational waveforms from binary black hole coalescence. Ten numerical relativity groups contributed numerical data which were used to generate a set of gravitational-wave signals. These signals were injected into a simulated data set, designed to mimic the response of the Initial LIGO and Virgo gravitational-wave detectors. Nine groups analysed this data using search and parameter-estimation pipelines. Matched filter algorithms, un-modelled-burst searches and Bayesian parameter-estimation and model-selection algorithms were applied to the data. We report the efficiency of these search methods in detecting the numerical waveforms and measuring their parameters. We describe preliminary comparisons between the different search methods and suggest improvements for future NINJA analyses.

Benjamin Aylott; John G. Baker; William D. Boggs; Michael Boyle; Patrick R. Brady; Duncan A. Brown; Bernd Brügmann; Luisa T. Buchman; Alessandra Buonanno; Laura Cadonati; Jordan Camp; Manuela Campanelli; Joan Centrella; Shourov Chatterji; Nelson Christensen; Tony Chu; Peter Diener; Nils Dorband; Zachariah B. Etienne; Joshua Faber; Stephen Fairhurst; Benjamin Farr; Sebastian Fischetti; Gianluca Guidi; Lisa M. Goggin; Mark Hannam; Frank Herrmann; Ian Hinder; Sascha Husa; Vicky Kalogera; Drew Keppel; Lawrence E. Kidder; Bernard J. Kelly; Badri Krishnan; Pablo Laguna; Carlos O. Lousto; Ilya Mandel; Pedro Marronetti; Richard Matzner; Sean T. McWilliams; Keith D. Matthews; R. Adam Mercer; Satyanarayan R. P. Mohapatra; Abdul H. Mroué; Hiroyuki Nakano; Evan Ochsner; Yi Pan; Larne Pekowsky; Harald P. Pfeiffer; Denis Pollney; Frans Pretorius; Vivien Raymond; Christian Reisswig; Luciano Rezzolla; Oliver Rinne; Craig Robinson; Christian Röver; Lucía Santamaría; Bangalore Sathyaprakash; Mark A. Scheel; Erik Schnetter; Jennifer Seiler; Stuart L. Shapiro; Deirdre Shoemaker; Ulrich Sperhake; Alexander Stroeer; Riccardo Sturani; Wolfgang Tichy; Yuk Tung Liu; Marc van der Sluys; James R. van Meter; Ruslan Vaulin; Alberto Vecchio; John Veitch; Andrea Viceré; John T. Whelan; Yosef Zlochower

2009-07-09T23:59:59.000Z

While these samples are representative of the content of NLE

they are not comprehensive nor are they the most current set.

We encourage you to perform a real-time search of NLE

to obtain the most current and comprehensive results.

341

We report results from a search for gravitational waves produced by perturbed intermediate mass black holes (IMBH) in data collected by LIGO and Virgo between 2005 and 2010. The search was sensitive to astrophysical sources that produced damped sinusoid gravitational wave signals, also known as ringdowns, with frequency $50\\le f_{0}/\\mathrm{Hz} \\le 2000$ and decay timescale $0.0001\\lesssim \\tau/\\mathrm{s} \\lesssim 0.1$ characteristic of those produced in mergers of IMBH pairs. No significant gravitational wave candidate was detected. We report upper limits on the astrophysical coalescence rates of IMBHs with total binary mass $50 \\le M/\\mathrm{M}_\\odot \\le 450$ and component mass ratios of either 1:1 or 4:1. For systems with total mass $100 \\le M/\\mathrm{M}_\\odot \\le 150$, we report a 90%-confidence upper limit on the rate of binary IMBH mergers with non-spinning and equal mass components of $6.9\\times10^{-8}\\,$Mpc$^{-3}$yr$^{-1}$. We also report a rate upper limit for ringdown waveforms from perturbed IMBHs, radiating 1% of their mass as gravitational waves in the fundamental, $\\ell=m=2$, oscillation mode, that is nearly three orders of magnitude more stringent than previous results.

The LIGO Scientific Collaboration; the Virgo Collaboration; J. Aasi; B. P. Abbott; R. Abbott; T. Abbott; M. R. Abernathy; F. Acernese; K. Ackley; C. Adams; T. Adams; P. Addesso; R. X. Adhikari; C. Affeldt; M. Agathos; N. Aggarwal; O. D. Aguiar; A. Ain; P. Ajith; A. Alemic; B. Allen; A. Allocca; D. Amariutei; M. Andersen; R. Anderson; S. B. Anderson; W. G. Anderson; K. Arai; M. C. Araya; C. Arceneaux; J. Areeda; S. M. Aston; P. Astone; P. Aufmuth; C. Aulbert; L. Austin; B. E. Aylott; S. Babak; P. T. Baker; G. Ballardin; S. W. Ballmer; J. C. Barayoga; M. Barbet; B. C. Barish; D. Barker; F. Barone; B. Barr; L. Barsotti; M. Barsuglia; M. A. Barton; I. Bartos; R. Bassiri; A. Basti; J. C. Batch; J. Bauchrowitz; Th. S. Bauer; V. Bavigadda; B. Behnke; M. Bejger; M . G. Beker; C. Belczynski; A. S. Bell; C. Bell; M. Benacquista; G. Bergmann; D. Bersanetti; A. Bertolini; J. Betzwieser; P. T. Beyersdorf; I. A. Bilenko; G. Billingsley; J. Birch; S. Biscans; M. Bitossi; M. A. Bizouard; E. Black; J. K. Blackburn; L. Blackburn; D. Blair; S. Bloemen; O. Bock; T. P. Bodiya; M. Boer; G. Bogaert; C. Bogan; C. Bond; F. Bondu; L. Bonelli; R. Bonnand; R. Bork; M. Born; V. Boschi; Sukanta Bose; L. Bosi; C. Bradaschia; P. R. Brady; V. B. Braginsky; M. Branchesi; J. E. Brau; T. Briant; D. O. Bridges; A. Brillet; M. Brinkmann; V. Brisson; A. F. Brooks; D. A. Brown; D. D. Brown; F. Brückner; S. Buchman; T. Bulik; H. J. Bulten; A. Buonanno; R. Burman; D. Buskulic; C. Buy; L. Cadonati; G. Cagnoli; J. Calderón Bustillo; E. Calloni; J. B. Camp; P. Campsie; K. C. Cannon; B. Canuel; J. Cao; C. D. Capano; F. Carbognani; L. Carbone; S. Caride; A. Castiglia; S. Caudill; M. Cavagliŕ; F. Cavalier; R. Cavalieri; C. Celerier; G. Cella; C. Cepeda; E. Cesarini; R. Chakraborty; T. Chalermsongsak; S. J. Chamberlin; S. Chao; P. Charlton; E. Chassande-Mottin; X. Chen; Y. Chen; A. Chincarini; A. Chiummo; H. S. Cho; J. Chow; N. Christensen; Q. Chu; S. S. Y. Chua; S. Chung; G. Ciani; F. Clara; J. A. Clark; F. Cleva; E. Coccia; P. -F. Cohadon; A. Colla; C. Collette; M. Colombini; L. Cominsky; M. Constancio Jr.; A. Conte; D. Cook; T. R. Corbitt; M. Cordier; N. Cornish; A. Corpuz; A. Corsi; C. A. Costa; M. W. Coughlin; S. Coughlin; J. -P. Coulon; S. Countryman; P. Couvares; D. M. Coward; M. Cowart; D. C. Coyne; R. Coyne; K. Craig; J. D. E. Creighton; S. G. Crowder; A. Cumming; L. Cunningham; E. Cuoco; K. Dahl; T. Dal Canton; M. Damjanic; S. L. Danilishin; S. D'Antonio; K. Danzmann; V. Dattilo; H. Daveloza; M. Davier; G. S. Davies; E. J. Daw; R. Day; T. Dayanga; G. Debreczeni; J. Degallaix; S. Deléglise; W. Del Pozzo; T. Denker; T. Dent; H. Dereli; V. Dergachev; R. De Rosa; R. T. DeRosa; R. DeSalvo; S. Dhurandhar; M. Díaz; L. Di Fiore; A. Di Lieto; I. Di Palma; A. Di Virgilio; V. Dolique; A. Donath; F. Donovan; K. L. Dooley; S. Doravari; S. Dossa; R. Douglas; T. P. Downes; M. Drago; R. W. P. Drever; J. C. Driggers; Z. Du; M. Ducrot; S. Dwyer; T. Eberle; T. Edo; M. Edwards; A. Effler; H. Eggenstein; P. Ehrens; J. Eichholz; S. S. Eikenberry; G. Endr\\Hoczi; R. Essick; T. Etzel; M. Evans; T. Evans; M. Factourovich; V. Fafone; S. Fairhurst; Q. Fang; S. Farinon; B. Farr; W. M. Farr; M. Favata; H. Fehrmann; M. M. Fejer; D. Feldbaum; F. Feroz; I. Ferrante; F. Ferrini; F. Fidecaro; L. S. Finn; I. Fiori; R. P. Fisher; R. Flaminio; J. -D. Fournier; S. Franco; S. Frasca; F. Frasconi; M. Frede; Z. Frei; A. Freise; R. Frey; T. T. Fricke; P. Fritschel; V. V. Frolov; P. Fulda; M. Fyffe; J. Gair; L. Gammaitoni; S. Gaonkar; F. Garufi; N. Gehrels; G. Gemme; B. Gendre; E. Genin; A. Gennai; S. Ghosh; J. A. Giaime; K. D. Giardina; A. Giazotto; C. Gill; J. Gleason; E. Goetz; R. Goetz; L. M. Goggin; L. Gondan; G. González; N. Gordon; M. L. Gorodetsky; S. Gossan; S. Goßler; R. Gouaty; C. Gräf; P. B. Graff; M. Granata; A. Grant; S. Gras; C. Gray; R. J. S. Greenhalgh; A. M. Gretarsson; P. Groot; H. Grote; K. Grover; S. Grunewald; G. M. Guidi; C. Guido; K. Gushwa; E. K. Gustafson; R. Gustafson; D. Hammer; G. Hammond; M. Hanke; J. Hanks; C. Hanna; J. Hanson; J. Harms; G. M. Harry; I. W. Harry; E. D. Harstad; M. Hart; M. T. Hartman; C. -J. Haster; K. Haughian; A. Heidmann; M. Heintze; H. Heitmann; P. Hello; G. Hemming; M. Hendry; I. S. Heng; A. W. Heptonstall; M. Heurs; M. Hewitson; S. Hild; D. Hoak; K. A. Hodge; K. Holt; S. Hooper; P. Hopkins; D. J. Hosken; J. Hough; E. J. Howell; Y. Hu; B. Hughey; S. Husa; S. H. Huttner; M. Huynh; T. Huynh-Dinh; D. R. Ingram; R. Inta; T. Isogai; A. Ivanov; B. R. Iyer; K. Izumi; M. Jacobson; E. James; H. Jang; P. Jaranowski; Y. Ji; F. Jiménez-Forteza; W. W. Johnson; D. I. Jones; R. Jones; R. J. G. Jonker; L. Ju; K. Haris; P. Kalmus; V. Kalogera; S. Kandhasamy; G. Kang; J. B. Kanner; J. Karlen; M. Kasprzack; E. Katsavounidis; W. Katzman; H. Kaufer; K. Kawabe; F. Kawazoe; F. Kéfélian; G. M. Keiser; D. Keitel; D. B. Kelley

2014-05-22T23:59:59.000Z

342

All-Sky LIGO Search for Periodic Gravitational Waves in the Early Fifth-Science-Run Data

We report on an all-sky search with the LIGO detectors for periodic gravitational waves in the frequency range 50–1100 Hz and with the frequency’s time derivative in the range -5×10[superscript -9]–0??Hz?s[superscript -1]. ...

Zucker, Michael E.

343

Search for gravitational waves from low mass binary coalescences in the first year of LIGO’s S5 data

We have searched for gravitational waves from coalescing low mass compact binary systems with a total mass between 2M[subscript ?] and 35M[subscript ?] and a minimum component mass of 1M[subscript ?] using data from the ...

Zucker, Michael E.

344

All-sky search for gravitational-wave bursts in the second joint LIGO-Virgo run

We present results from a search for gravitational-wave bursts in the data collected by the LIGO and Virgo detectors between July 7, 2009 and October 20, 2010: data are analyzed when at least two of the three LIGO-Virgo ...

Barsotti, Lisa

345

In this paper we present the results of a coherent narrow-band search for continuous gravitational-wave signals from the Crab and Vela pulsars conducted on Virgo VSR4 data. In order to take into account a possible small ...

Aasi, J.

346

The equation of state plays a critical role in the physics of the merger of two neutron stars. Recent numerical simulations with microphysical equation of state suggest the outcome of such events depends on the mass of the neutron stars. For less massive systems, simulations favor the formation of a hypermassive, quasi-stable neutron star, whose oscillations produce a short, high frequency burst of gravitational radiation. Its dominant frequency content is tightly correlated with the radius of the neutron star, and its measurement can be used to constrain the supranuclear equation of state. In contrast, the merger of higher mass systems results in prompt gravitational collapse to a black hole. We have developed an algorithm which combines waveform reconstruction from a morphology-independent search for gravitational wave transients with Bayesian model selection, to discriminate between post-merger scenarios and accurately measure the dominant oscillation frequency. We demonstrate the efficacy of the method using a catalogue of simulated binary merger signals in data from LIGO and Virgo, and we discuss the prospects for this analysis in advanced ground-based gravitational wave detectors. From the waveforms considered in this work and assuming an optimally oriented source, we find that the post-merger neutron star signal may be detectable by this technique to $\\sim 10\\text{--}25$\\,Mpc. We also find that we successfully discriminate between the post-merger scenarios with $\\sim 95\\%$ accuracy and determine the dominant oscillation frequency of surviving post-merger neutron stars to within $\\sim 10$\\,Hz, averaged over all detected signals. This leads to an uncertainty in the estimated radius of a non-rotating 1.6\\,M$_{\\odot}$ reference neutron star of $\\sim 100\\,$m.

J. Clark; A. Bauswein; L. Cadonati; H. -T. Janka; C. Pankow; N. Stergioulas

2014-06-20T23:59:59.000Z

347

Impact of Higher Harmonics in Searching for Gravitational Waves from Non-Spinning Binary Black Holes

Current searches for gravitational waves from coalescing binary black holes (BBH) use templates that only include the dominant harmonic. In this study we use effective-one-body multipolar waveforms calibrated to numerical-relativity simulations to quantify the effect of neglecting sub-dominant harmonics on the sensitivity of searches. We consider both signal-to-noise ratio (SNR) and the signal-based vetoes that are used to re-weight SNR. We find that neglecting sub-dominant modes when searching for non-spinning BBHs with component masses $3\\,M_{\\odot} \\leq m_1, m_2 \\leq 200\\,M_{\\odot}$ and total mass $M advanced LIGO results in a negligible reduction of the re-weighted SNR at detection thresholds. Sub-dominant modes therefore have no effect on the detection rates predicted for advanced LIGO. Furthermore, we find that if sub-dominant modes are included in templates the sensitivity of the search becomes worse if we use current search priors, due to an increase in false alarm probability. Templates would need to be weighted differently than what is currently done to compensate for the increase in false alarms. If we split the template bank such that sub-dominant modes are only used when $M \\gtrsim 100\\,M_{\\odot}$ and mass ratio $q \\gtrsim 4$, we find that the sensitivity does improve for these intermediate mass-ratio BBHs, but the sensitive volume associated with these systems is still small compared to equal-mass systems. Using sub-dominant modes is therefore unlikely to substantially increase the probability of detecting gravitational waves from non-spinning BBH signals unless there is a relatively large population of intermediate mass-ratio BBHs in the universe.

Collin Capano; Yi Pan; Alessandra Buonanno

2014-03-31T23:59:59.000Z

348

Improving the detectability of gravitational wave counterparts of short hard gamma ray bursts .

??With multiple observatories and missions being planned for detecting orphaned afterglows associated with gamma-ray bursts (GRBs) we emphasize the importance of developing data analysis strategies… (more)

[No author

2013-01-01T23:59:59.000Z

349

The ``optical bars''/``optical lever'' topologies of gravitational-wave antennae allow to obtain sensitivity better that the Standard Quantum Limit while keeping the optical pumping energy in the antenna relatively low. Element of the crucial importance in these schemes is the local meter which monitors the local test mirror position. Using cross-correlation of this meter back-action noise and its measurement noise it is possible to further decrease the optical pumping energy. In this case the pumping energy minimal value will be limited by the internal losses in the antenna only. Estimates show that for values of parameters available for contemporary and planned gravitational-wave antennae, sensitivity about one order of magnitude better than the Standard Quantum Limit can be obtained using the pumping energy about one order of magnitude smaller energy than is required in the traditional topology in order to obtain the the Standard Quantum Limit level of sensitivity.

F. Ya. Khalili

2003-04-16T23:59:59.000Z

350

Interaction of linearized gravitational waves with a otherwise free particle has been studied quantum mechanically in a noncommutative phase-space to examine whether the particle's response to the gravitational wave gets modified due to spatial and/or momentum noncommutativity. The result shows that momentum noncommutativity introduces a oscillatory noise with a specific frequency determined by the fundamental momentum scale and particle mass. Because of the global nature of the phase-space noncommutativity such noise will have similar characteristics for all detector sites and thus will stand out in a data cross-correlation procedure. If detected, this noise will provide evidence of momentum noncommutativity and also an estimation of the relevant noncommutative parameter.

Sunandan Gangopadhyay; Anirban Saha; Swarup Saha

2014-01-27T23:59:59.000Z

351

We analyze the propagation of gravitational waves (GWs) in an asymptotically de-Sitter space by expanding the perturbation around Minkowski and introducing the effects of the Cosmological Constant ($\\Lambda$), first as an additional source (de-Donder gauge) and after as a gauge effect ($\\Lambda$-gauge). In both cases the inclusion of the Cosmological Constant $\\Lambda$ impedes the detection of a gravitational wave at a distance larger than $L_{crit}=(6\\sqrt{2}\\pi f \\hat{h}/\\sqrt{5})r_\\Lambda^2$, where $r_\\Lambda=\\frac{1}{\\sqrt{\\Lambda}}$ and f and $\\hat{h}$ are the frequency and strain of the wave respectively. We demonstrate that $L_{crit}$ is just a confirmation of the Cosmic No hair Conjecture (CNC) already explained in the literature.

Ivan Arraut

2013-01-26T23:59:59.000Z

352

Quantifying and mitigating bias in inference on gravitational wave source populations

When using incorrect or inaccurate signal models to perform parameter estimation on a gravitational wave signal, biased parameter estimates will in general be obtained. For a single event this bias may be consistent with the posterior, but when considering a population of events this bias becomes evident as a sag below the expected diagonal line of the P-P plot showing the fraction of signals found within a certain significance level versus that significance level. It would be hoped that recently proposed techniques for accounting for model uncertainties in parameter estimation would, to some extent, alleviate this problem. Here we demonstrate that this is indeed the case. We derive an analytic approximation to the P-P plot obtained when using an incorrect signal model to perform parameter estimation. This approximation is valid in the limit of high signal-to-noise ratio and nearly correct waveform models. We show how the P-P plot changes if a Gaussian process likelihood that allows for model errors is used t...

Gair, Jonathan R

2015-01-01T23:59:59.000Z

353

We provide calculations and theoretical arguments supporting the emission of electromagnetic radiation from charged particles accelerated by gravitational waves (GWs). These waves have significant indirect evidence to support their existence, yet they interact weakly with ordinary matter. We show that the induced oscillations of charged particles interacting with a GW, which lead to the emission of electromagnetic radiation, will also result in wave attenuation. These ideas are supported by a small body of literature, as well as additional arguments for particle acceleration based on GW memory effects. We derive order of magnitude power calculations for various initial charge distributions accelerated by GWs. The resulting power emission is extremely small for all but very strong GWs interacting with large quantities of charge. If the results here are confirmed and supplemented, significant consequences such as attenuation of early universe GWs could result. Additionally, this effect could extend GW detection techniques into the electromagnetic regime. These explorations are worthy of study to determine the presence of such radiation, as it is extremely important to refine our theoretical framework in an era of active GW astrophysics.

Mitchell Revalski; Will Rhodes; Thulsi Wickramasinghe

2015-02-03T23:59:59.000Z

354

Compact binary systems with neutron stars or black holes are one of the most promising sources for ground-based gravitational wave detectors. Gravitational radiation encodes rich information about source physics; thus parameter estimation and model selection are crucial analysis steps for any detection candidate events. Detailed models of the anticipated waveforms enable inference on several parameters, such as component masses, spins, sky location and distance that are essential for new astrophysical studies of these sources. However, accurate measurements of these parameters and discrimination of models describing the underlying physics are complicated by artifacts in the data, uncertainties in the waveform models and in the calibration of the detectors. Here we report such measurements on a selection of simulated signals added either in hardware or software to the data collected by the two LIGO instruments and the Virgo detector during their most recent joint science run, including a "blind injection" where the signal was not initially revealed to the collaboration. We exemplify the ability to extract information about the source physics on signals that cover the neutron star and black hole parameter space over the individual mass range 1 Msun - 25 Msun and the full range of spin parameters. The cases reported in this study provide a snap-shot of the status of parameter estimation in preparation for the operation of advanced detectors.

the LIGO Scientific Collaboration; the Virgo Collaboration; J. Aasi; J. Abadie; B. P. Abbott; R. Abbott; T. D. Abbott; M. Abernathy; T. Accadia; F. Acernese; C. Adams; T. Adams; P. Addesso; R. Adhikari; C. Affeldt; M. Agathos; K. Agatsuma; P. Ajith; B. Allen; A. Allocca; E. Amador Ceron; D. Amariutei; S. B. Anderson; W. G. Anderson; K. Arai; M. C. Araya; S. Ast; S. M. Aston; P. Astone; D. Atkinson; P. Aufmuth; C. Aulbert; B. E. Aylott; S. Babak; P. Baker; G. Ballardin; S. Ballmer; Y. Bao; J. C. B. Barayoga; D. Barker; F. Barone; B. Barr; L. Barsotti; M. Barsuglia; M. A. Barton; I. Bartos; R. Bassiri; M. Bastarrika; A. Basti; J. Batch; J. Bauchrowitz; Th. S. Bauer; M. Bebronne; D. Beck; B. Behnke; M. Bejger; M. G. Beker; A. S. Bell; C. Bell; I. Belopolski; M. Benacquista; J. M. Berliner; A. Bertolini; J. Betzwieser; N. Beveridge; P. T. Beyersdorf; T. Bhadbade; I. A. Bilenko; G. Billingsley; J. Birch; R. Biswas; M. Bitossi; M. A. Bizouard; E. Black; J. K. Blackburn; L. Blackburn; D. Blair; B. Bland; M. Blom; O. Bock; T. P. Bodiya; C. Bogan; C. Bond; R. Bondarescu; F. Bondu; L. Bonelli; R. Bonnand; R. Bork; M. Born; V. Boschi; S. Bose; L. Bosi; B. Bouhou; S. Braccini; C. Bradaschia; P. R. Brady; V. B. Braginsky; M. Branchesi; J. E. Brau; J. Breyer; T. Briant; D. O. Bridges; A. Brillet; M. Brinkmann; V. Brisson; M. Britzger; A. F. Brooks; D. A. Brown; T. Bulik; H. J. Bulten; A. Buonanno; J. Burguet--Castell; D. Buskulic; C. Buy; R. L. Byer; L. Cadonati; G. Cagnoli; E. Calloni; J. B. Camp; P. Campsie; K. Cannon; B. Canuel; J. Cao; C. D. Capano; F. Carbognani; L. Carbone; S. Caride; S. Caudill; M. Cavagliŕ; F. Cavalier; R. Cavalieri; G. Cella; C. Cepeda; E. Cesarini; T. Chalermsongsak; P. Charlton; E. Chassande-Mottin; W. Chen; X. Chen; Y. Chen; A. Chincarini; A. Chiummo; H. S. Cho; J. Chow; N. Christensen; S. S. Y. Chua; C. T. Y. Chung; S. Chung; G. Ciani; F. Clara; D. E. Clark; J. A. Clark; J. H. Clayton; F. Cleva; E. Coccia; P. -F. Cohadon; C. N. Colacino; A. Colla; M. Colombini; A. Conte; R. Conte; D. Cook; T. R. Corbitt; M. Cordier; N. Cornish; A. Corsi; C. A. Costa; M. Coughlin; J. -P. Coulon; P. Couvares; D. M. Coward; M. Cowart; D. C. Coyne; J. D. E. Creighton; T. D. Creighton; A. M. Cruise; A. Cumming; L. Cunningham; E. Cuoco; R. M. Cutler; K. Dahl; M. Damjanic; S. L. Danilishin; S. D'Antonio; K. Danzmann; V. Dattilo; B. Daudert; H. Daveloza; M. Davier; E. J. Daw; T. Dayanga; R. De Rosa; D. DeBra; G. Debreczeni; J. Degallaix; W. Del Pozzo; T. Dent; V. Dergachev; R. DeRosa; S. Dhurandhar; L. Di Fiore; A. Di Lieto; I. Di Palma; M. Di Paolo Emilio; A. Di Virgilio; M. Díaz; A. Dietz; F. Donovan; K. L. Dooley; S. Doravari; S. Dorsher; M. Drago; R. W. P. Drever; J. C. Driggers; Z. Du; J. -C. Dumas; S. Dwyer; T. Eberle; M. Edgar; M. Edwards; A. Effler; P. Ehrens; G. Endröczi; R. Engel; T. Etzel; K. Evans; M. Evans; T. Evans; M. Factourovich; V. Fafone; S. Fairhurst; B. F. Farr; W. M. Farr; M. Favata; D. Fazi; H. Fehrmann; D. Feldbaum; F. Feroz; I. Ferrante; F. Ferrini; F. Fidecaro; L. S. Finn; I. Fiori; R. P. Fisher; R. Flaminio; S. Foley; E. Forsi; L. A. Forte; N. Fotopoulos; J. -D. Fournier; J. Franc; S. Franco; S. Frasca; F. Frasconi; M. Frede; M. A. Frei; Z. Frei; A. Freise; R. Frey; T. T. Fricke; D. Friedrich; P. Fritschel; V. V. Frolov; M. -K. Fujimoto; P. J. Fulda; M. Fyffe; J. Gair; M. Galimberti; L. Gammaitoni; J. Garcia; F. Garufi; M. E. Gáspár; G. Gelencser; G. Gemme; E. Genin; A. Gennai; L. Á. Gergely; S. Ghosh; J. A. Giaime; S. Giampanis; K. D. Giardina; A. Giazotto; S. Gil-Casanova; C. Gill; J. Gleason; E. Goetz; G. González; M. L. Gorodetsky; S. Goßler; R. Gouaty; C. Graef; P. B. Graff; M. Granata; A. Grant; C. Gray; R. J. S. Greenhalgh; A. M. Gretarsson; C. Griffo; H. Grote; K. Grover; S. Grunewald; G. M. Guidi; C. Guido; R. Gupta; E. K. Gustafson; R. Gustafson; J. M. Hallam; D. Hammer; G. Hammond; J. Hanks; C. Hanna; J. Hanson; J. Harms; G. M. Harry; I. W. Harry; E. D. Harstad; M. T. Hartman; C. -J. Haster; K. Haughian; K. Hayama; J. -F. Hayau; J. Heefner; A. Heidmann; M. C. Heintze; H. Heitmann; P. Hello; G. Hemming; M. A. Hendry; I. S. Heng; A. W. Heptonstall; V. Herrera; M. Heurs; M. Hewitson; S. Hild; D. Hoak; K. A. Hodge; K. Holt; M. Holtrop; T. Hong; S. Hooper; J. Hough; E. J. Howell; B. Hughey; S. Husa; S. H. Huttner; T. Huynh-Dinh; D. R. Ingram; R. Inta; T. Isogai; A. Ivanov; K. Izumi; M. Jacobson; E. James; Y. J. Jang; P. Jaranowski; E. Jesse; W. W. Johnson; D. I. Jones; R. Jones; R. J. G. Jonker; L. Ju; P. Kalmus; V. Kalogera; S. Kandhasamy; G. Kang; J. B. Kanner; M. Kasprzack; R. Kasturi; E. Katsavounidis; W. Katzman; H. Kaufer; K. Kaufman; K. Kawabe; S. Kawamura; F. Kawazoe; D. Keitel; D. Kelley; W. Kells; D. G. Keppel; Z. Keresztes; A. Khalaidovski; F. Y. Khalili; E. A. Khazanov; B. K. Kim; C. Kim; H. Kim; K. Kim; N. Kim; Y. M. Kim; P. J. King

2013-10-22T23:59:59.000Z

355

Search for long-lived gravitational-wave transients coincident with long gamma-ray bursts

Long gamma-ray bursts (GRBs) have been linked to extreme core-collapse supernovae from massive stars. Gravitational waves (GW) offer a probe of the physics behind long GRBs. We investigate models of long-lived (~10-1000s) GW emission associated with the accretion disk of a collapsed star or with its protoneutron star remnant. Using data from LIGO's fifth science run, and GRB triggers from the swift experiment, we perform a search for unmodeled long-lived GW transients. Finding no evidence of GW emission, we place 90% confidence level upper limits on the GW fluence at Earth from long GRBs for three waveforms inspired by a model of GWs from accretion disk instabilities. These limits range from F<3.5 ergs cm^-2 to $F<1200 ergs cm^-2, depending on the GRB and on the model, allowing us to probe optimistic scenarios of GW production out to distances as far as ~33 Mpc. Advanced detectors are expected to achieve strain sensitivities 10x better than initial LIGO, potentially allowing us to probe the engines of the nearest long GRBs.

The LIGO Scientific Collaboration; the Virgo Collaboration; J. Aasi; J. Abadie; B. P. Abbott; R. Abbott; T. Abbott; M. R. Abernathy; T. Accadia; F. Acernese; C. Adams; T. Adams; R. X. Adhikari; C. Affeldt; M. Agathos; N. Aggarwal; O. D. Aguiar; P. Ajith; B. Allen; A. Allocca; E. Amador Ceron; D. Amariutei; R. A. Anderson; S. B. Anderson; W. G. Anderson; K. Arai; M. C. Araya; C. Arceneaux; J. Areeda; S. Ast; S. M. Aston; P. Astone; P. Aufmuth; C. Aulbert; L. Austin; B. E. Aylott; S. Babak; P. T. Baker; G. Ballardin; S. W. Ballmer; J. C. Barayoga; D. Barker; S. H. Barnum; F. Barone; B. Barr; L. Barsotti; M. Barsuglia; M. A. Barton; I. Bartos; R. Bassiri; A. Basti; J. Batch; J. Bauchrowitz; Th. S. Bauer; M. Bebronne; B. Behnke; M. Bejger; M. G. Beker; A. S. Bell; C. Bell; I. Belopolski; G. Bergmann; J. M. Berliner; D. Bersanetti; A. Bertolini; D. Bessis; J. Betzwieser; P. T. Beyersdorf; T. Bhadbhade; I. A. Bilenko; G. Billingsley; J. Birch; M. Bitossi; M. A. Bizouard; E. Black; J. K. Blackburn; L. Blackburn; D. Blair; M. Blom; O. Bock; T. P. Bodiya; M. Boer; C. Bogan; C. Bond; F. Bondu; L. Bonelli; R. Bonnand; R. Bork; M. Born; V. Boschi; S. Bose; L. Bosi; J. Bowers; C. Bradaschia; P. R. Brady; V. B. Braginsky; M. Branchesi; C. A. Brannen; J. E. Brau; J. Breyer; T. Briant; D. O. Bridges; A. Brillet; M. Brinkmann; V. Brisson; M. Britzger; A. F. Brooks; D. A. Brown; D. D. Brown; F. Br; T. Bulik; H. J. Bulten; A. Buonanno; D. Buskulic; C. Buy; R. L. Byer; L. Cadonati; G. Cagnoli; J. Calderon Bustillo; E. Calloni; J. B. Camp; P. Campsie; K. C. Cannon; B. Canuel; J. Cao; C. D. Capano; F. Carbognani; L. Carbone; S. Caride; A. Castiglia; S. Caudill; M. Cavagli; F. Cavalier; R. Cavalieri; G. Cella; C. Cepeda; E. Cesarini; R. Chakraborty; T. Chalermsongsak; S. Chao; P. Charlton; E. Chassande-Mottin; X. Chen; Y. Chen; A. Chincarini; A. Chiummo; H. S. Cho; J. Chow; N. Christensen; Q. Chu; S. S. Y. Chua; S. Chung; G. Ciani; F. Clara; D. E. Clark; J. A. Clark; F. Cleva; E. Coccia; P. -F. Cohadon; A. Colla; M. Colombini; M. Constancio Jr.; A. Conte; R. Conte; D. Cook; T. R. Corbitt; M. Cordier; N. Cornish; A. Corsi; C. A. Costa; M. W. Coughlin; J. -P. Coulon; S. Countryman; P. Couvares; D. M. Coward; M. Cowart; D. C. Coyne; K. Craig; J. D. E. Creighton; T. D. Creighton; S. G. Crowder; A. Cumming; L. Cunningham; E. Cuoco; K. Dahl; T. Dal Canton; M. Damjanic; S. L. Danilishin; S. D'Antonio; K. Danzmann; V. Dattilo; B. Daudert; H. Daveloza; M. Davier; G. S. Davies; E. J. Daw; R. Day; T. Dayanga; R. De Rosa; G. Debreczeni; J. Degallaix; W. Del Pozzo; E. Deleeuw; S. Deleglise; T. Denker; T. Dent; H. Dereli; V. Dergachev; R. DeRosa; R. DeSalvo; S. Dhurandhar; L. Di Fiore; A. Di Lieto; I. Di Palma; A. Di Virgilio; M. Diaz; A. Dietz; K. Dmitry; F. Donovan; K. L. Dooley; S. Doravari; M. Drago; R. W. P. Drever; J. C. Driggers; Z. Du; J. -C. Dumas; S. Dwyer; T. Eberle; M. Edwards; A. Effler; P. Ehrens; J. Eichholz; S. S. Eikenberry; G. EndrH; R. Essick; T. Etzel; K. Evans; M. Evans; T. Evans; M. Factourovich; V. Fafone; S. Fairhurst; Q. Fang; S. Farinon; B. Farr; W. Farr; M. Favata; D. Fazi; H. Fehrmann; D. Feldbaum; I. Ferrante; F. Ferrini; F. Fidecaro; L. S. Finn; I. Fiori; R. Fisher; R. Flaminio; E. Foley; S. Foley; E. Forsi; N. Fotopoulos; J. -D. Fournier; S. Franco; S. Frasca; F. Frasconi; M. Frede; M. Frei; Z. Frei; A. Freise; R. Frey; T. T. Fricke; P. Fritschel; V. V. Frolov; M. -K. Fujimoto; P. Fulda; M. Fyffe; J. Gair; L. Gammaitoni; J. Garcia; F. Garufi; N. Gehrels; G. Gemme; E. Genin; A. Gennai; L. Gergely; S. Ghosh; J. A. Giaime; S. Giampanis; K. D. Giardina; A. Giazotto; S. Gil-Casanova; C. Gill; J. Gleason; E. Goetz; R. Goetz; L. Gondan; G. Gonzalez; N. Gordon; M. L. Gorodetsky; S. Gossan; S. Go; R. Gouaty; C. Graef; P. B. Graff; M. Granata; A. Grant; S. Gras; C. Gray; R. J. S. Greenhalgh; A. M. Gretarsson; C. Griffo; P. Groot; H. Grote; K. Grover; S. Grunewald; G. M. Guidi; C. Guido; K. E. Gushwa; E. K. Gustafson; R. Gustafson; B. Hall; E. Hall; D. Hammer; G. Hammond; M. Hanke; J. Hanks; C. Hanna; J. Hanson; J. Harms; G. M. Harry; I. W. Harry; E. D. Harstad; M. T. Hartman; K. Haughian; K. Hayama; J. Heefner; A. Heidmann; M. Heintze; H. Heitmann; P. Hello; G. Hemming; M. Hendry; I. S. Heng; A. W. Heptonstall; M. Heurs; S. Hild; D. Hoak; K. A. Hodge; K. Holt; M. Holtrop; T. Hong; S. Hooper; T. Horrom; D. J. Hosken; J. Hough; E. J. Howell; Y. Hu; Z. Hua; V. Huang; E. A. Huerta; B. Hughey; S. Husa; S. H. Huttner; M. Huynh; T. Huynh-Dinh; J. Iafrate; D. R. Ingram; R. Inta; T. Isogai; A. Ivanov; B. R. Iyer; K. Izumi; M. Jacobson; E. James; H. Jang; Y. J. Jang; P. Jaranowski; F. Jimenez-Forteza; W. W. Johnson; D. Jones; D. I. Jones; R. Jones; R. J. G. Jonker; L. Ju; Haris K; P. Kalmus; V. Kalogera; S. Kandhasamy; G. Kang; J. B. Kanner; M. Kasprzack; R. Kasturi; E. Katsavounidis; W. Katzman; H. Kaufer; K. Kaufman

2013-12-09T23:59:59.000Z

356

Bright broad-band afterglows of gravitational wave bursts from mergers of binary neutron stars

If double neutron star mergers leave behind a massive magnetar rather than a black hole, a bright early afterglow can follow the gravitational wave burst (GWB) even if there is no short gamma-ray burst (SGRB) - GWB association or there is an association but the SGRB does not beam towards earth. Besides directly dissipating the proto-magnetar wind as suggested by Zhang, we here suggest that the magnetar wind could push the ejecta launched during the merger process, and under certain conditions, would reach a relativistic speed. Such a magnetar-powered ejecta, when interacting with the ambient medium, would develop a bright broad-band afterglow due to synchrotron radiation. We study this physical scenario in detail, and present the predicted X-ray, optical and radio light curves for a range of magnetar and ejecta parameters. We show that the X-ray and optical lightcurves usually peak around the magnetar spindown time scale (10^3-10^5s), reaching brightness readily detectable by wide-field X-ray and optical telescopes, and remain detectable for an extended period. The radio afterglow peaks later, but is much brighter than the case without a magnetar energy injection. Therefore, such bright broad-band afterglows, if detected and combined with GWBs in the future, would be a probe of massive millisecond magnetars and stiff equation-of-state for nuclear matter.

He Gao; Xuan Ding; Xue-Feng Wu; Bing Zhang; Zi-Gao Dai

2013-01-03T23:59:59.000Z

357

CBR Anisotropy from Primordial Gravitational Waves in Two-Component Inflationary Cosmology

We examine stochastic temperature fluctuations of the cosmic background radiation (CBR) arising via the Sachs-Wolfe effect from gravitational wave perturbations produced in the early universe. We consider spatially flat, perturbed FRW models that begin with an inflationary phase, followed by a mixed phase containing both radiation and dust. The scale factor during the mixed phase takes the form $a(\\eta)=c_1\\eta^2+c_2\\eta+c_3$, where $c_i$ are constants. During the mixed phase the universe smoothly transforms from being radiation to dust dominated. We find analytic expressions for the graviton mode function during the mixed phase in terms of spheroidal wave functions. This mode function is used to find an analytic expression for the multipole moments $\\langle a_l^2\\rangle$ of the two-point angular correlation function $C(\\gamma)$ for the CBR anisotropy. The analytic expression for the multipole moments is written in terms of two integrals, which are evaluated numerically. The results are compared to multipoles calculated for models that are {\\it completely} dust dominated at last-scattering. We find that the multipoles $\\langle a_l^2\\rangle$ of the CBR temperature perturbations for $l>10$ are significantly larger for a universe that contains both radiation and dust at last-scattering. We compare our results with recent, similar numerical work and find good agreement. The spheroidal wave functions may have applications to other problems of cosmological interest.

Scott Koranda; Bruce Allen

1994-10-20T23:59:59.000Z

358

REANALYSIS OF F-STATISTIC GRAVITATIONAL-WAVE SEARCHES WITH THE HIGHER CRITICISM STATISTIC

We propose a new method of gravitational-wave detection using a modified form of higher criticism, a statistical technique introduced by Donoho and Jin. Higher criticism is designed to detect a group of sparse, weak sources, none of which are strong enough to be reliably estimated or detected individually. We apply higher criticism as a second-pass method to synthetic F-statistic and C-statistic data for a monochromatic periodic source in a binary system and quantify the improvement relative to the first-pass methods. We find that higher criticism on C-statistic data is more sensitive by {approx}6% than the C-statistic alone under optimal conditions (i.e., binary orbit known exactly) and the relative advantage increases as the error in the orbital parameters increases. Higher criticism is robust even when the source is not monochromatic (e.g., phase-wandering in an accreting system). Applying higher criticism to a phase-wandering source over multiple time intervals gives a {approx}> 30% increase in detectability with few assumptions about the frequency evolution. By contrast, in all-sky searches for unknown periodic sources, which are dominated by the brightest source, second-pass higher criticism does not provide any benefits over a first-pass search.

Bennett, M. F.; Melatos, A. [School of Physics, University of Melbourne, Parkville, VIC 3010 (Australia)] [School of Physics, University of Melbourne, Parkville, VIC 3010 (Australia); Delaigle, A.; Hall, P., E-mail: mfb@unimelb.edu.au [Department of Mathematics and Statistics, University of Melbourne, Parkville, VIC 3010 (Australia)

2013-04-01T23:59:59.000Z

359

The multi-detector F-statistic is close to optimal for detecting continuous gravitational waves (CWs) in Gaussian noise. However, it is susceptible to false alarms from instrumental artefacts, for example quasi-monochromatic disturbances ('lines'), which resemble a CW signal more than Gaussian noise. In a recent paper [Keitel et al 2014, PRD 89 064023], a Bayesian model selection approach was used to derive line-robust detection statistics for CW signals, generalising both the F-statistic and the F-statistic consistency veto technique and yielding improved performance in line-affected data. Here we investigate a generalisation of the assumptions made in that paper: if a CW analysis uses data from two or more detectors with very different sensitivities, the line-robust statistics could be less effective. We investigate the boundaries within which they are still safe to use, in comparison with the F-statistic. Tests using synthetic draws show that the optimally-tuned version of the original line-robust statistic remains safe in most cases of practical interest. We also explore a simple idea on further improving the detection power and safety of these statistics, which we however find to be of limited practical use.

David Keitel; Reinhard Prix

2015-01-16T23:59:59.000Z

360

Spectral properties of the post-merger gravitational-wave signal from binary neutron stars

Extending previous work by a number of authors, we have recently presented a new approach in which the detection of gravitational waves from merging neutron star binaries can be used to determine the equation of state of matter at nuclear density and hence the structure of neutron stars. In particular, after performing a large number of numerical-relativity simulations of binaries with nuclear equations of state, we have found that the post-merger emission is characterized by two distinct and robust spectral features. While the high-frequency peak was already shown to be associated with the oscillations of the hypermassive neutron star produced by the merger and to depend on the equation of state, we have highlighted that the low-frequency peak is related to the merger process and to the total compactness of the stars in the binary. This relation is essentially universal and provides a powerful tool to set tight constraints on the equation of state. We here provide additional information on the extensive analysis performed, illustrating the methods used, the tests considered, and the robustness of the results. We also discuss additional relations that can be deduced when exploring the data and how these correlate with various properties of the binary. Finally, we present a simple mechanical toy model that explains the main spectral features of the post-merger signal and can even reproduce analytically the complex waveforms emitted right after the merger.

Kentaro Takami; Luciano Rezzolla; Luca Baiotti

2014-12-10T23:59:59.000Z

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361

The cosmic strings(CSs) may be one important source of gravitational waves(GWs), and it has been intensively studied due to its special properties such as the cylindrical symmetry. The CSs would generate not only usual continuous GW, but also impulsive GW that brings more concentrated energy and consists of different GW components broadly covering low-, intermediate- and high-frequency bands simultaneously. These features might underlie interesting electromagnetic(EM) response to these GWs generated by the CSs. In this paper, with novel results and effects, we firstly calculate the analytical solutions of perturbed EM fields caused by interaction between impulsive cylindrical GWs (would be one of possible forms emitted from CSs) and background celestial high magnetic fields or widespread cosmological background magnetic fields, by using rigorous Einstein - Rosen metric. Results show: perturbed EM fields are also in the impulsive form accordant to the GW pulse, and asymptotic behaviors of the perturbed EM fields are fully consistent with the asymptotic behaviors of the energy density, energy flux density and Riemann curvature tensor of corresponding impulsive cylindrical GWs. The analytical solutions naturally give rise to the accumulation effect which is proportional to the term of distance^1/2, and based on it, we for the first time predict potentially observable effects in region of the Earth caused by the EM response to GWs from the CSs.

H. Wen; F. Y. Li; Z. Y. Fang; A. Beckwith

2014-05-04T23:59:59.000Z

362

Reconstruction of source location in a network of gravitational wave interferometric detectors

This paper deals with the reconstruction of the direction of a gravitational wave source using the detection made by a network of interferometric detectors, mainly the LIGO and Virgo detectors. We suppose that an event has been seen in coincidence using a filter applied on the three detector data streams. Using the arrival time (and its associated error) of the gravitational signal in each detector, the direction of the source in the sky is computed using a {chi}{sup 2} minimization technique. For reasonably large signals (SNR>4.5 in all detectors), the mean angular error between the real location and the reconstructed one is about 1 deg. . We also investigate the effect of the network geometry assuming the same angular response for all interferometric detectors. It appears that the reconstruction quality is not uniform over the sky and is degraded when the source approaches the plane defined by the three detectors. Adding at least one other detector to the LIGO-Virgo network reduces the blind regions and in the case of 6 detectors, a precision less than 1 deg. on the source direction can be reached for 99% of the sky.

Cavalier, Fabien; Barsuglia, Matteo; Bizouard, Marie-Anne; Brisson, Violette; Clapson, Andre-Claude; Davier, Michel; Hello, Patrice; Kreckelbergh, Stephane; Leroy, Nicolas; Varvella, Monica [Laboratoire de l'Accelerateur Lineaire, IN2P3-CNRS et Universite Paris-Sud 11, Centre Scientifique d'Orsay, B.P. 34, 91898 Orsay Cedex (France)

2006-10-15T23:59:59.000Z

363

The gravitational-wave signal generated by a galactic population of double neutron-star binaries

We investigate the gravitational wave (GW) signal generated by a population of double neutron-star binaries (DNS) with eccentric orbits caused by kicks during supernova collapse and binary evolution. The DNS population of a standard Milky-Way type galaxy has been studied as a function of star formation history, initial mass function (IMF) and metallicity and of the binary-star common-envelope ejection process. The model provides birth rates, merger rates and total numbers of DNS as a function of time. The GW signal produced by this population has been computed and expressed in terms of a hypothetical space GW detector (eLISA) by calculating the number of discrete GW signals at different confidence levels, where `signal' refers to detectable GW strain in a given frequency-resolution element. In terms of the parameter space explored, the number of DNS-originating GW signals is greatest in regions of recent star formation, and is significantly increased if metallicity is reduced from 0.02 to 0.001, consistent wi...

Yu, Shenghua

2015-01-01T23:59:59.000Z

364

The Challenges in Gravitational Wave Astronomy for Space-Based Detectors

The Gravitational Wave (GW) universe contains a wealth of sources which, with the proper treatment, will open up the universe as never before. By observing massive black hole binaries to high redshifts, we should begin to explore the formation process of seed black holes and track galactic evolution to the present day. Observations of extreme mass ratio inspirals will allow us to explore galactic centers in the local universe, as well as providing tests of General Relativity and constraining the value of Hubble's constant. The detection of compact binaries in our own galaxy may allow us to model stellar evolution in the Milky Way. Finally, the detection of cosmic (super)strings and a stochastic background would help us to constrain cosmological models. However, all of this depends on our ability to not only resolve sources and carry out parameter estimation, but also on our ability to define an optimal data analysis strategy. In this presentation, I will examine the challenges that lie ahead in GW astronomy for the ESA L3 Cosmic Vision mission, eLISA.

Edward K. Porter

2014-06-26T23:59:59.000Z

365

Coincidence searches of gravitational waves and short gamma-ray bursts

Black-hole neutron-star coalescing binaries have been invoked as one of the most suitable scenario to explain the emission of short gamma-ray bursts. Indeed, if the black-hole which forms after the merger, is surrounded by a massive disk, neutrino annihilation processes may produce high-energy and collimated electromagnetic radiation. In this paper, we devise a new procedure, to be used in the search for gravitational waves from black-hole-neutron-star binaries, to assign a probability that a detected gravitational signal is associated to the formation of an accreting disk, massive enough to power gamma-ray bursts. This method is based on two recently proposed semi-analytic fits, one reproducing the mass of the remnant disk surrounding the black hole as a function of some binary parameters, the second relating the neutron star compactness, with its tidal deformability. Our approach can be used in low-latency data analysis to restrict the parameter space searching for gravitational signals associated with short gamma-ray bursts, and to gain information on the dynamics of the coalescing system and on the neutron star equation of state.

Andrea Maselli; Valeria Ferrari

2014-05-28T23:59:59.000Z

366

BRIGHT BROADBAND AFTERGLOWS OF GRAVITATIONAL WAVE BURSTS FROM MERGERS OF BINARY NEUTRON STARS

If double neutron star mergers leave behind a massive magnetar rather than a black hole, then a bright early afterglow can follow the gravitational wave burst (GWB) even if there is no short gamma-ray burst (SGRB)-GWB association or if there is an association but the SGRB does not beam toward Earth. Besides directly dissipating the proto-magnetar wind, as suggested by Zhang, here we suggest that the magnetar wind could push the ejecta launched during the merger process and, under certain conditions, would reach a relativistic speed. Such a magnetar-powered ejecta, when interacting with the ambient medium, would develop a bright broadband afterglow due to synchrotron radiation. We study this physical scenario in detail and present the predicted X-ray, optical, and radio light curves for a range of magnetar and ejecta parameters. We show that the X-ray and optical light curves usually peak around the magnetar spin-down timescale ({approx}10{sup 3}-10{sup 5} s), reaching brightnesses readily detectable by wide-field X-ray and optical telescopes, and remain detectable for an extended period. The radio afterglow peaks later, but is much brighter than the case without a magnetar energy injection. Therefore, such bright broadband afterglows, if detected and combined with GWBs in the future, would be a probe of massive millisecond magnetars and stiff equations of state for nuclear matter.

Gao He; Ding Xuan; Wu Xuefeng [Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008 (China); Zhang Bing [Department of Physics and Astronomy, University of Nevada, Las Vegas, NV 89154 (United States); Dai Zigao, E-mail: xfwu@pmo.ac.cn, E-mail: zhang@physics.unlv.edu, E-mail: dzg@nju.edu.cn [School of Astronomy and Space Science, Nanjing University, Nanjing 210093 (China)

2013-07-10T23:59:59.000Z

367

Lattice template placement for coherent all-sky searches for gravitational-wave pulsars

All-sky, broadband, coherent searches for gravitational-wave pulsars are restricted by limited computational resources. Minimizing the number of templates required to cover the search parameter space, of sky position and frequency evolution, is one important way to reduce the computational cost of a search. We demonstrate a practical algorithm which, for the first time, achieves template placement with a minimal number of templates for an all-sky search, using the reduced supersky parameter-space metric of Wette and Prix [Phys. Rev. D 88, 123005 (2013)]. The metric prescribes a constant template density in the signal parameters, which permits that templates be placed at the vertices of a lattice. We demonstrate how to ensure complete coverage of the parameter space, including in particular at its boundaries. The number of templates generated by the algorithm is compared to theoretical estimates, and to previous predictions by Brady et al. [Phys. Rev. D 57, 2101 (1998)]. The algorithm may be applied to any search parameter space with a constant template density, which includes semicoherent searches and searches targeting known low-mass X-ray binaries.

Karl Wette

2014-12-22T23:59:59.000Z

368

A large heat load caused by thermal radiation through a metal shield pipe was observed in a cooling test of a cryostat for a prototype of a cryogenic interferometric gravitational wave detector. The heat load was approximately 1000 times larger than the value calculated by the Stefan-Boltzmann law. We studied this phenomenon by simulation and experiment and found that it was caused by the conduction of thermal radiation in a metal shield pipe.

Takayuki Tomaru; Masao Tokunari; Kazuaki Kuroda; Takashi Uchiyama; Akira Okutomi; Masatake Ohashi; Hiroyuki Kirihara; Nobuhiro Kimura; Yoshio Saito; Nobuaki Sato; Takakazu Shintomi; Toshikazu Suzuki; Tomiyoshi Haruyama; Shinji Miyoki; Kazuhiro Yamamoto; Akira Yamamoto

2007-11-06T23:59:59.000Z

369

We elucidate the feature of gravitational waves (GWs) from binary neutron star merger collapsing to a black hole by general relativistic simulation. We show that GW spectrum imprints the coalescence dynamics, formation process of disk, equation of state for neutron stars, total masses, and mass ratio. A formation mechanism of the central engine of short $\\gamma$-ray bursts, which are likely to be composed of a black hole and surrounding disk, therefore could be constrained by GW observation.

Kenta Kiuchi; Yuichiro Sekiguchi; Masaru Shibata; Keisuke Taniguchi

2010-02-13T23:59:59.000Z

370

We report a novel application of graphics processing units (GPUs) for the purpose of accelerating the search pipelines for gravitational waves from coalescing binaries of compact objects. A speed-up of 16 fold has been achieved compared with a single central processing unit (CPU). We show that substantial improvements are possible and discuss the reduction in CPU count required for the detection of inspiral sources afforded by the use of GPUs.

Shin Kee Chung; Linqing Wen; David Blair; Kipp Cannon; Amitava Datta

2010-05-17T23:59:59.000Z

371

Progenitor scenarios for short gamma-ray bursts (short GRBs) include coalescenses of two neutron stars or a neutron star and black hole, which would necessarily be accompanied by the emission of strong gravitational waves. ...

Barsotti, Lisa

372

We report on a search for gravitational waves from coalescing compact binaries using LIGO and Virgo observations between July 7, 2009, and October 20, 2010. We searched for signals from binaries with total mass between 2 ...

Barsotti, Lisa

373

Strange quark matter (SQM) may be the true ground state of hadronic matter, indicating that the observed pulsars may actually be strange stars, but not neutron stars. According to this SQM hypothesis, the existence of a hydrostatically stable sequence of strange quark matter stars has been predicted, ranging from 1 --- 2 solar mass strange stars, to smaller strange dwarfs and even strange planets. While gravitational wave (GW) astronomy is expected to open a new window to the universe, it will shed light on the searching for SQM stars. Here we show that due to their extreme compactness, strange planets can spiral very close to their host strange stars, without being tidally disrupted. Like inspiraling neutron stars or black holes, these systems would serve as a new kind of sources for GW bursts, producing strong gravitational waves at the final stage. The events occurring in our local Universe can be detected by the upcoming gravitational wave detectors, such as Advanced LIGO and the Einstein Telescope. This ...

Geng, J J; Lu, T

2015-01-01T23:59:59.000Z

374

EARLY X-RAY AND OPTICAL AFTERGLOW OF GRAVITATIONAL WAVE BURSTS FROM MERGERS OF BINARY NEUTRON STARS

Double neutron star mergers are strong sources of gravitational waves. The upcoming advanced gravitational wave detectors are expected to make the first detection of gravitational wave bursts (GWBs) associated with these sources. Proposed electromagnetic counterparts of a GWB include a short gamma-ray burst, an optical macronova, and a long-lasting radio afterglow. Here we suggest that at least some GWBs could be followed by an early afterglow lasting for thousands of seconds, if the post-merger product is a highly magnetized, rapidly rotating, massive neutron star rather than a black hole. This afterglow is powered by dissipation of a proto-magnetar wind. The X-ray flux is estimated to be as bright as (10{sup -8}-10{sup -7}) erg s{sup -1} cm{sup -2}. The optical flux is subject to large uncertainties but could be as bright as 17th magnitude in R band. We provide observational hints of such a scenario, and discuss the challenge and strategy to detect these signals.

Zhang Bing [Kavli Institute of Astronomy and Astrophysics, Peking University, Beijing 100871 (China)

2013-01-20T23:59:59.000Z

375

The coalescence of massive black holes generates gravitational waves (GWs) that will be measurable by space-based detectors such as LISA to large redshifts. The spins of a binary's black holes have an important impact on its waveform. Specifically, geodetic and gravitomagnetic effects cause the spins to precess; this precession then modulates the waveform, adding periodic structure which encodes useful information about the binary's members. Following pioneering work by Vecchio, we examine the impact upon GW measurements of including these precession-induced modulations in the waveform model. We find that the additional periodicity due to spin precession breaks degeneracies among certain parameters, greatly improving the accuracy with which they may be measured. In particular, mass measurements are improved tremendously, by one to several orders of magnitude. Localization of the source on the sky is also improved, though not as much--low redshift systems can be localized to an ellipse which is roughly 10-a fewx10 arcminutes in the long direction and a factor of 2 smaller in the short direction. Though not a drastic improvement relative to analyses which neglect spin precession, even modest gains in source localization will greatly facilitate searches for electromagnetic counterparts to GW events. Determination of distance to the source is likewise improved: We find that relative error in measured luminosity distance is commonly {approx}0.1%-0.4% at z{approx}1. Finally, with the inclusion of precession, we find that the magnitude of the spins themselves can typically be determined for low redshift systems with an accuracy of about 0.1%-10%, depending on the spin value, allowing accurate surveys of mass and spin evolution over cosmic time.

Lang, Ryan N.; Hughes, Scott A. [Department of Physics and MIT Kavli Institute, MIT, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139 (United States)

2006-12-15T23:59:59.000Z

376

Recently exploratory studies were performed on the possibility of constraining the neutron star equation of state (EOS) using signals from coalescing binary neutron stars, or neutron star-black hole systems, as they will be seen in upcoming advanced gravitational wave detectors such as Advanced LIGO and Advanced Virgo. In particular, it was estimated to what extent the combined information from multiple detections would enable one to distinguish between different equations of state through hypothesis ranking or parameter estimation. Under the assumption of zero neutron star spins both in signals and in template waveforms and considering tidal effects to 1PN order, it was found that O(20) sources would suffice to distinguish between a hard, moderate, and soft equation of state. Here we revisit these results, this time including neutron star tidal effects to the highest order currently known, termination of gravitational waveforms at the contact frequency, neutron star spins, and the resulting quadrupole-monopole interaction. We also take the masses of neutron stars in simulated sources to be distributed according to a relatively strongly peaked Gaussian, as hinted at by observations, but without assuming that the data analyst will necessarily have accurate knowledge of this distribution for use as a mass prior. We find that especially the effect of the latter is dramatic, necessitating many more detections to distinguish between different EOS and causing systematic biases in parameter estimation, on top of biases due to imperfect understanding of the signal model pointed out in earlier work. This would get mitigated if reliable prior information about the mass distribution could be folded into the analyses.

Michalis Agathos; Jeroen Meidam; Walter Del Pozzo; Tjonnie G. F. Li; Marco Tompitak; John Veitch; Salvatore Vitale; Chris Van Den Broeck

2015-03-18T23:59:59.000Z

377

All non-twisting Petrov-type N solutions of vacuum Einstein field equations with cosmological constant Lambda are summarized. They are shown to belong either to the non-expanding Kundt class or to the expanding Robinson-Trautman class. Invariant subclasses of each class are defined and the corresponding metrics are given explicitly in suitable canonical coordinates. Relations between the subclasses and their geometrical properties are analyzed. In the subsequent paper these solutions are interpreted as exact gravitational waves propagating in de Sitter or anti-de Sitter spacetimes.

J. Bicak; J. Podolsky

1999-07-13T23:59:59.000Z

378

Report on an all-sky LIGO search for periodic gravitational waves in the S4 data

We report on an all-sky search with the LIGO detectors for periodic gravitational waves in the frequency range 50-1000 Hz and having a negative frequency time derivative with magnitude between zero and $10^{-8}$ Hz/s. Data from the fourth LIGO science run have been used in this search. Three different semi-coherent methods of summing strain power were applied. Observing no evidence for periodic gravitational radiation, we report upper limits on strain amplitude and interpret these limits to constrain radiation from rotating neutron stars.

Alicia M. Sintes; for the LIGO Scientific Collaboration

2007-10-25T23:59:59.000Z

379

We present the results of a search for gravitational waves associated with 154 gamma-ray bursts (GRBs) that were detected by satellite-based gamma-ray experiments in 2009-2010, during the sixth LIGO science run and the second and third Virgo science runs. We perform two distinct searches: a modeled search for coalescences of either two neutron stars or a neutron star and black hole; and a search for generic, unmodeled gravitational-wave bursts. We find no evidence for gravitational-wave counterparts, either with any individual GRB in this sample or with the population as a whole. For all GRBs we place lower bounds on the distance to the progenitor, under the optimistic assumption of a gravitational-wave emission energy of 10^-2 M c^2 at 150 Hz, with a median limit of 17 Mpc. For short hard GRBs we place exclusion distances on binary neutron star and neutron star-black hole progenitors, using astrophysically motivated priors on the source parameters, with median values of 16 Mpc and 28 Mpc respectively. These distance limits, while significantly larger than for a search that is not aided by GRB satellite observations, are not large enough to expect a coincidence with a GRB. However, projecting these exclusions to the sensitivities of Advanced LIGO and Virgo, which should begin operation in 2015, we find that the detection of gravitational waves associated with GRBs will become quite possible.

The LIGO Scientific Collaboration; Virgo Collaboration; J. Abadie; B. P. Abbott; R. Abbott; T. D. Abbott; M. Abernathy; T. Accadia; F. Acernese; C. Adams; R. Adhikari; C. Affeldt; M. Agathos; K. Agatsuma; P. Ajith; B. Allen; E. Amador Ceron; D. Amariutei; S. B. Anderson; W. G. Anderson; K. Arai; M. A. Arain; M. C. Araya; S. M. Aston; P. Astone; D. Atkinson; P. Aufmuth; C. Aulbert; B. E. Aylott; S. Babak; P. Baker; G. Ballardin; S. Ballmer; J. C. B. Barayoga; D. Barker; F. Barone; B. Barr; L. Barsotti; M. Barsuglia; M. A. Barton; I. Bartos; R. Bassiri; M. Bastarrika; A. Basti; J. Batch; J. Bauchrowitz; Th. S. Bauer; M. Bebronne; D. Beck; B. Behnke; M. Bejger; M. G. Beker; A. S. Bell; I. Belopolski; M. Benacquista; J. M. Berliner; A. Bertolini; J. Betzwieser; N. Beveridge; P. T. Beyersdorf; I. A. Bilenko; G. Billingsley; J. Birch; R. Biswas; M. Bitossi; M. A. Bizouard; E. Black; J. K. Blackburn; L. Blackburn; D. Blair; B. Bland; M. Blom; O. Bock; T. P. Bodiya; C. Bogan; R. Bondarescu; F. Bondu; L. Bonelli; R. Bonnand; R. Bork; M. Born; V. Boschi; S. Bose; L. Bosi; B. Bouhou; S. Braccini; C. Bradaschia; P. R. Brady; V. B. Braginsky; M. Branchesi; J. E. Brau; J. Breyer; T. Briant; D. O. Bridges; A. Brillet; M. Brinkmann; V. Brisson; M. Britzger; A. F. Brooks; D. A. Brown; T. Bulik; H. J. Bulten; A. Buonanno; J. Burguet--Castell; D. Buskulic; C. Buy; R. L. Byer; L. Cadonati; E. Calloni; J. B. Camp; P. Campsie; J. Cannizzo; K. Cannon; B. Canuel; J. Cao; C. D. Capano; F. Carbognani; L. Carbone; S. Caride; S. Caudill; M. Cavagliŕ; F. Cavalier; R. Cavalieri; G. Cella; C. Cepeda; E. Cesarini; O. Chaibi; T. Chalermsongsak; P. Charlton; E. Chassande-Mottin; S. Chelkowski; W. Chen; X. Chen; Y. Chen; A. Chincarini; A. Chiummo; H. S. Cho; J. Chow; N. Christensen; S. S. Y. Chua; C. T. Y. Chung; S. Chung; G. Ciani; F. Clara; D. E. Clark; J. Clark; J. H. Clayton; F. Cleva; E. Coccia; P. -F. Cohadon; C. N. Colacino; J. Colas; A. Colla; M. Colombini; A. Conte; R. Conte; D. Cook; T. R. Corbitt; M. Cordier; N. Cornish; A. Corsi; C. A. Costa; M. Coughlin; J. -P. Coulon; P. Couvares; D. M. Coward; M. Cowart; D. C. Coyne; J. D. E. Creighton; T. D. Creighton; A. M. Cruise; A. Cumming; L. Cunningham; E. Cuoco; R. M. Cutler; K. Dahl; S. L. Danilishin; R. Dannenberg; S. D'Antonio; K. Danzmann; V. Dattilo; B. Daudert; H. Daveloza; M. Davier; E. J. Daw; R. Day; T. Dayanga; R. De Rosa; D. DeBra; G. Debreczeni; J. Degallaix; W. Del Pozzo; M. del Prete; T. Dent; V. Dergachev; R. DeRosa; R. DeSalvo; S. Dhurandhar; L. Di Fiore; A. Di Lieto; I. Di Palma; M. Di Paolo Emilio; A. Di Virgilio; M. Díaz; A. Dietz; F. Donovan; K. L. Dooley; M. Drago; R. W. P. Drever; J. C. Driggers; Z. Du; J. -C. Dumas; S. Dwyer; T. Eberle; M. Edgar; M. Edwards; A. Effler; P. Ehrens; G. Endröczi; R. Engel; T. Etzel; K. Evans; M. Evans; T. Evans; M. Factourovich; V. Fafone; S. Fairhurst; Y. Fan; B. F. Farr; D. Fazi; H. Fehrmann; D. Feldbaum; F. Feroz; I. Ferrante; F. Fidecaro; L. S. Finn; I. Fiori; R. P. Fisher; R. Flaminio; M. Flanigan; S. Foley; E. Forsi; L. A. Forte; N. Fotopoulos; J. -D. Fournier; J. Franc; S. Franco; S. Frasca; F. Frasconi; M. Frede; M. Frei; Z. Frei; A. Freise; R. Frey; T. T. Fricke; D. Friedrich; P. Fritschel; V. V. Frolov; M. -K. Fujimoto; P. J. Fulda; M. Fyffe; J. Gair; M. Galimberti; L. Gammaitoni; J. Garcia; F. Garufi; M. E. Gáspár; N. Gehrels; G. Gemme; R. Geng; E. Genin; A. Gennai; L. Á. Gergely; S. Ghosh; J. A. Giaime; S. Giampanis; K. D. Giardina; A. Giazotto; S. Gil-Casanova; C. Gill; J. Gleason; E. Goetz; L. M. Goggin; G. González; M. L. Gorodetsky; S. Goßler; R. Gouaty; C. Graef; P. B. Graff; M. Granata; A. Grant; S. Gras; C. Gray; N. Gray; R. J. S. Greenhalgh; A. M. Gretarsson; C. Greverie; R. Grosso; H. Grote; S. Grunewald; G. M. Guidi; C. Guido; R. Gupta; E. K. Gustafson; R. Gustafson; T. Ha; J. M. Hallam; D. Hammer; G. Hammond; J. Hanks; C. Hanna; J. Hanson; A. Hardt; J. Harms; G. M. Harry; I. W. Harry; E. D. Harstad; M. T. Hartman; K. Haughian; K. Hayama; J. -F. Hayau; J. Heefner; A. Heidmann; M. C. Heintze; H. Heitmann; P. Hello; M. A. Hendry; I. S. Heng; A. W. Heptonstall; V. Herrera; M. Hewitson; S. Hild; D. Hoak; K. A. Hodge; K. Holt; M. Holtrop; T. Hong; S. Hooper; D. J. Hosken; J. Hough; E. J. Howell; B. Hughey; S. Husa; S. H. Huttner; T. Huynh-Dinh; D. R. Ingram; R. Inta; T. Isogai; A. Ivanov; K. Izumi; M. Jacobson; E. James; Y. J. Jang; P. Jaranowski; E. Jesse; W. W. Johnson; D. I. Jones; G. Jones; R. Jones; R. J. G. Jonker; L. Ju; P. Kalmus; V. Kalogera; S. Kandhasamy; G. Kang; J. B. Kanner; R. Kasturi; E. Katsavounidis; W. Katzman; H. Kaufer; K. Kawabe; S. Kawamura; F. Kawazoe; D. Kelley; W. Kells; D. G. Keppel; Z. Keresztes; A. Khalaidovski; F. Y. Khalili; E. A. Khazanov; B. K. Kim; C. Kim; H. Kim; K. Kim; N. Kim; Y. M. Kim; P. J. King; D. L. Kinzel; J. S. Kissel; S. Klimenko; K. Kokeyama

2012-09-24T23:59:59.000Z

380

We present the results of a search for gravitational waves associated with 154 gamma-ray bursts (GRBs) that were detected by satellite-based gamma-ray experiments in 2009-2010, during the sixth LIGO science run and the second and third Virgo science runs. We perform two distinct searches: a modeled search for coalescences of either two neutron stars or a neutron star and black hole, and a search for generic, unmodeled gravitational-wave bursts. We find no evidence for gravitational-wave counterparts, either with any individual GRB in this sample or with the population as a whole. For all GRBs we place lower bounds on the distance to the progenitor, under the optimistic assumption of a gravitational-wave emission energy of 10{sup -2} M {sub Sun} c {sup 2} at 150 Hz, with a median limit of 17 Mpc. For short-hard GRBs we place exclusion distances on binary neutron star and neutron-star-black-hole progenitors, using astrophysically motivated priors on the source parameters, with median values of 16 Mpc and 28 Mpc, respectively. These distance limits, while significantly larger than for a search that is not aided by GRB satellite observations, are not large enough to expect a coincidence with a GRB. However, projecting these exclusions to the sensitivities of Advanced LIGO and Virgo, which should begin operation in 2015, we find that the detection of gravitational waves associated with GRBs will become quite possible.

Abadie, J.; Abbott, B. P.; Abbott, R.; Adhikari, R. X.; Ajith, P.; Anderson, S. B.; Arai, K. [LIGO-California Institute of Technology, Pasadena, CA 91125 (United States); Abbott, T. D. [California State University Fullerton, Fullerton, CA 92831 (United States); Abernathy, M. [SUPA, University of Glasgow, Glasgow G12 8QQ (United Kingdom); Accadia, T. [Laboratoire d'Annecy-le-Vieux de Physique des Particules (LAPP), Universite de Savoie, CNRS/IN2P3, F-74941 Annecy-Le-Vieux (France); Acernese, F. [INFN, Sezione di Napoli, Complesso Universitario di Monte S. Angelo, I-80126 Napoli (Italy); Adams, C. [LIGO-Livingston Observatory, Livingston, LA 70754 (United States); Affeldt, C.; Allen, B. [Albert-Einstein-Institut, Max-Planck-Institut fuer Gravitationsphysik, D-30167 Hannover (Germany); Agathos, M. [Nikhef, Science Park, Amsterdam (Netherlands); Agatsuma, K. [National Astronomical Observatory of Japan, Tokyo 181-8588 (Japan); Ceron, E. Amador; Anderson, W. G. [University of Wisconsin-Milwaukee, Milwaukee, WI 53201 (United States); Amariutei, D.; Arain, M. A. [University of Florida, Gainesville, FL 32611 (United States); Collaboration: LIGO Scientific Collaboration; Virgo Collaboration; and others

2012-11-20T23:59:59.000Z

While these samples are representative of the content of NLE

they are not comprehensive nor are they the most current set.

We encourage you to perform a real-time search of NLE

to obtain the most current and comprehensive results.

381

We study the effect of spins on searches for gravitational waves from compact binary coalescences in realistic simulated early advanced LIGO data. We construct a detection pipeline including matched filtering, signal-based vetoes, a coincidence test between different detectors, and an estimate of the rate of background events. We restrict attention to neutron star--black hole (NS-BH) binary systems, and we compare a search using non-spinning templates to one using templates that include spins aligned with the orbital angular momentum. To run the searches we implement the binary inspiral matched-filter computation in PyCBC, a new software toolkit for gravitational-wave data analysis. We find that the inclusion of aligned-spin effects significantly increases the astrophysical reach of the search. Considering astrophysical NS-BH systems with non-precessing black hole spins, for dimensionless spin components along the orbital angular momentum uniformly distributed in $(-1, 1)$, the sensitive volume of the search with aligned-spin templates is increased by $\\sim 50\\%$ compared to the non-spinning search; for signals with aligned spins uniformly distributed in the range $(0.7,1)$, the increase in sensitive volume is a factor of $\\sim 10$.

Tito Dal Canton; Alexander H. Nitz; Andrew P. Lundgren; Alex B. Nielsen; Duncan A. Brown; Thomas Dent; Ian W. Harry; Badri Krishnan; Andrew J. Miller; Karl Wette; Karsten Wiesner; Joshua L. Willis

2014-10-27T23:59:59.000Z

382

We report the construction of a three-dimensional template bank for the search for gravitational waves from inspiralling binaries consisting of spinning compact objects. The parameter space consists of two dimensions describing the mass parameters and one "reduced-spin" parameter, which describes the secular (non-precessing) spin effects in the waveform. The template placement is based on an efficient stochastic algorithm and makes use of the semi-analytical computation of a metric in the parameter space. We demonstrate that for "low-mass" ($m_1 + m_2 \\lesssim 12\\,M_\\odot$) binaries, this template bank achieves effective fitting factors $\\sim0.92$--$0.99$ towards signals from generic spinning binaries in the advanced detector era over the entire parameter space of interest (including binary neutron stars, binary black holes, and black hole-neutron star binaries). This provides a powerful and viable method for searching for gravitational waves from generic spinning low-mass compact binaries. Under the assumption that spin magnitudes of black-holes [neutron-stars] are uniformly distributed between 0--0.98 [0 -- 0.4] and spin angles are isotropically distributed, the expected improvement in the average detection volume (at a fixed signal-to-noise-ratio threshold) of a search using this reduced-spin bank is $\\sim20-52\\%$, as compared to a search using a non-spinning bank.

P. Ajith; N. Fotopoulos; S. Privitera; A. Neunzert; N. Mazumder; A. J. Weinstein

2014-05-21T23:59:59.000Z

383

The recent measurement of the Shapiro delay in the radio pulsar PSR J1614-2230 yielded a mass of 1.97 +/- 0.04 M_sun, making it the most massive pulsar known to date. Its mass is high enough that, even without an accompanying measurement of the stellar radius, it has a strong impact on our understanding of nuclear matter, gamma-ray bursts, and the generation of gravitational waves from coalescing neutron stars. This single high mass value indicates that a transition to quark matter in neutron-star cores can occur at densities comparable to the nuclear saturation density only if the quarks are strongly interacting and are color superconducting. We further show that a high maximum neutron-star mass is required if short duration gamma-ray bursts are powered by coalescing neutron stars and, therefore, this mechanism becomes viable in the light of the recent measurement. Finally, we argue that the low-frequency (<= 500 Hz) gravitational waves emitted during the final stages of neutron-star coalescence encode the properties of the equation of state because neutron stars consistent with this measurement cannot be centrally condensed. This will facilitate the measurement of the neutron star equation of state with Advanced LIGO/Virgo.

Feryal Ozel; Dimitrios Psaltis; Scott Ransom; Paul Demorest; Mark Alford

2010-10-27T23:59:59.000Z

384

We propose a procedure to be used in the search for gravitational waves from black hole-neutron star coalescing binaries, in coincidence with short gamma-ray bursts. It is based on two recently proposed semi-analytic fits, one reproducing the mass of the remnant disk surrounding the black hole which forms after the merging as a function of some binary parameters, the second relating the neutron star compactness, i.e. the ratio of mass and radius, with its tidal deformability. Using a Fisher matrix analysis and the two fits, we assign a probability that the emitted gravitational signal is associated to the formation of an accreting disk massive enough to supply the energy needed to power a short gamma ray burst. This information can be used in low-latency data analysis to restrict the parameter space searching for gravitational wave signals in coincidence with short gamma-ray bursts, and to gain information on the dynamics of the coalescing system and on the internal structure of the components. In addition, when the binary parameters will be measured with high accuracy, it will be possible to use this information to trigger the search for off-axis gamma-ray bursts afterglows.

Andrea Maselli; Valeria Ferrari

2014-02-24T23:59:59.000Z

385

It is shown that the axial and polar perturbations of the spherically symmetric black hole can be described in a gauge-invariant way. The reduced phase space describing gravitational waves outside of the horizon is described by the gauge-invariant quantities. Both degrees of freedom fulfill generalized scalar wave equation. For the axial degree of freedom the radial part of the equation corresponds to the Regge-Wheeler result (Phys. Rev. 108, 1063-1069 (1957)) and for the polar one we get Zerilli result (Phys. Rev. D2, 2141-2160 (1970)), see also Chandrasekhar (The Mathematical Theory of Black Holes,(Clarendon Press Oxford, 1983)), Moncrief (Annals of Physics 88, 323-342 (1974)) for both. An important ingredient of the analysis is the concept of quasilocality which does duty for the separation of the angular variables in the usual approach. Moreover, there is no need to represent perturbations by normal modes (with time dependence $\\exp(-ikt)$), we have fields in spacetime and the Cauchy problem for them is well defined outside of the horizon. The reduced symplectic structure explains the origin of the axial and polar invariants. It allows to introduce an energy and angular momentum for the gravitational waves which is invariant with respect to the gauge transformations. Both generators represent quadratic approximation of the ADM nonlinear formulae in terms of the perturbations of the Schwarzschild metric. We also discuss the boundary-initial value problem for the linearized Einstein equations on a Schwarzschild background outside of the horizon.

Jacek Jezierski

1998-01-20T23:59:59.000Z

386

A double-pass interferometer is provided which allows direct measurement of relative displacement between opposed surfaces. A conventional plane mirror interferometer may be modified by replacing the beam-measuring path cube-corner reflector with an additional quarterwave plate. The beam path is altered to extend to an opposed plane mirrored surface and the reflected beam is placed in interference with a retained reference beam split from dual-beam source and retroreflected by a reference cube-corner reflector mounted stationary with the interferometer housing. This permits direct measurement of opposed mirror surfaces by laser interferometry while doubling the resolution as with a conventional double-pass plane mirror laser interferometer system.

Pardue, R.M.; Williams, R.R.

1980-09-12T23:59:59.000Z

387

We present the first numerical-relativity simulation of a compact-object binary whose gravitational waveform is long enough to cover the entire frequency band of advanced gravitational-wave detectors, such as LIGO, Virgo and KAGRA, for mass ratio 7 and total mass as low as $45.5\\,M_\\odot$. We find that effective-one-body models, either uncalibrated or calibrated against substantially shorter numerical-relativity waveforms at smaller mass ratios, reproduce our new waveform remarkably well, with a negligible loss in detection rate due to modeling error. In contrast, post-Newtonian inspiral waveforms and existing calibrated phenomenological inspiral-merger-ringdown waveforms display greater disagreement with our new simulation. The disagreement varies substantially depending on the specific post-Newtonian approximant used.

Szilagyi, Bela; Buonanno, Alessandra; Taracchini, Andrea; Pfeiffer, Harald P; Scheel, Mark A; Chu, Tony; Kidder, Lawrence E; Pan, Yi

2015-01-01T23:59:59.000Z

388

We present the first numerical-relativity simulation of a compact-object binary whose gravitational waveform is long enough to cover the entire frequency band of advanced gravitational-wave detectors, such as LIGO, Virgo and KAGRA, for mass ratio 7 and total mass as low as $45.5\\,M_\\odot$. We find that effective-one-body models, either uncalibrated or calibrated against substantially shorter numerical-relativity waveforms at smaller mass ratios, reproduce our new waveform remarkably well, with a negligible loss in detection rate due to modeling error. In contrast, post-Newtonian inspiral waveforms and existing calibrated phenomenological inspiral-merger-ringdown waveforms display greater disagreement with our new simulation. The disagreement varies substantially depending on the specific post-Newtonian approximant used.

Bela Szilagyi; Jonathan Blackman; Alessandra Buonanno; Andrea Taracchini; Harald P. Pfeiffer; Mark A. Scheel; Tony Chu; Lawrence E. Kidder; Yi Pan

2015-02-17T23:59:59.000Z

389

Searches for gravitational waves (GWs) from binary black holes using interferometric GW detectors require the construction of template banks for performing matched filtering while analyzing the data. Placement of templates over the parameter space of binaries, as well as coincidence tests of GW triggers from multiple detectors make use of the definition of a metric over the space of gravitational waveforms. Although recent searches have employed waveform templates coherently describing the inspiral, merger and ringdown (IMR) of the coalescence, the metric used in the template banks and coincidence tests was derived from post-Newtonian inspiral waveforms. In this paper, we compute the template-space metric of the IMR waveform family IMRPhenomB over the parameter space of masses and the effective spin parameter. We also propose a coordinate system, which is a modified version of post-Newtonian chirp time coordinates, in which the metric is slowly varying over the parameter space. The match function analytically...

Kalaghatgi, Chinmay; Arun, K G

2015-01-01T23:59:59.000Z

390

We use realistic Monte-Carlo simulations including both gravitational-wave and short gamma-ray burst selection effects to revisit the coincident rate of binary systems composed of two neutron stars or a neutron star and a black hole. We show that the fraction of GW triggers that can be observed in coincidence with sGRBs is proportional to the beaming factor at $z=0$, but increases with the distance, until it reaches 100 \\% at the GW detector horizon distance. When this is taken into account the rate is improved by a factor of $~3$ compared to the simple beaming factor correction. We provide an estimate of the performance future GRB detectors should achieve in order to fully exploit the potentiality of the planned third generation GW antenna Einstein Telescope, and we propose a simple method to constrain the beaming angle of sGRBs.

Regimbau, T; Meacher, D; Gendre, B; er, M Bo\\"

2014-01-01T23:59:59.000Z

391

The geometry around a rotating massive body, which carries charge and electrical currents, could be described by its multipole moments (mass moments, mass-current moments, electric moments, and magnetic moments). When a small body is orbiting this massive body, it will move on geodesics, at least for a time interval that is short with respect to the characteristic time of the binary due to gravitational radiation. By monitoring the waves emitted by the small body we are actually tracing the geometry of the central object, and hence, in principle, we can infer all its multipole moments. This paper is a generalization of previous similar results by Ryan. The fact that the electromagnetic moments of spacetime can be measured demonstrates that one can obtain information about the electromagnetic field purely from gravitational wave analysis. Additionally, these measurements could be used as a test of the no-hair theorem for black holes.

T. P. Sotiriou; T. A. Apostolatos

2004-10-25T23:59:59.000Z

392

We present an inflationary model preceded by a bounce in a metric theory a l\\'{a} $f(R)$ where $R$ is the scalar curvature of the space-time. The model is asymptotically de Sitter such that the gravitational action tends asymptotically to a Hilbert-Einstein action, therefore modified gravity affects only the early stages of the universe. We then analyse the spectrum of the gravitational waves through the method of the Bogoliubov coefficients by two means: taking into account the gravitational perturbations due to the modified gravitational action in the $f(R)$ setup and by simply considering those perturbations inherent to the standard Hilbert-Einstein action. We show that there are distinctive (oscillatory) signals on the spectrum for very low frequencies; i.e. corresponding to modes that are currently entering the horizon.

Mariam Bouhmadi-Lopez; Joao Morais; Alfredo B. Henriques

2013-05-02T23:59:59.000Z

393

We present the results of a search for gravitational waves associated with 154 gamma-ray bursts (GRBs) that were detected by satellite-based gamma-ray experiments in 2009-2010, during the sixth LIGO science run and the ...

Bodiya, Timothy Paul

394

In this paper we report on a search for short-duration gravitational wave bursts in the frequency range 64 Hz–1792 Hz associated with gamma-ray bursts (GRBs), using data from GEO 600 and one of the LIGO or Virgo detectors. ...

Aggarwal, Nancy

395

Design of a dual species atom interferometer for space

Atom interferometers have a multitude of proposed applications in space including precise measurements of the Earth's gravitational field, in navigation & ranging, and in fundamental physics such as tests of the weak equivalence principle (WEP) and gravitational wave detection. While atom interferometers are realized routinely in ground-based laboratories, current efforts aim at the development of a space compatible design optimized with respect to dimensions, weight, power consumption, mechanical robustness and radiation hardness. In this paper, we present a design of a high-sensitivity differential dual species $^{85}$Rb/$^{87}$Rb atom interferometer for space, including physics package, laser system, electronics and software. The physics package comprises the atom source consisting of dispensers and a 2D magneto-optical trap (MOT), the science chamber with a 3D-MOT, a magnetic trap based on an atom chip and an optical dipole trap (ODT) used for Bose-Einstein condensate (BEC) creation and interferometry, the detection unit, the vacuum system for $10^{-11}$ mbar ultra-high vacuum generation, and the high-suppression factor magnetic shielding as well as the thermal control system. The laser system is based on a hybrid approach using fiber-based telecom components and high-power laser diode technology and includes all laser sources for 2D-MOT, 3D-MOT, ODT, interferometry and detection. Manipulation and switching of the laser beams is carried out on an optical bench using Zerodur bonding technology. The instrument consists of 9 units with an overall mass of 221 kg, an average power consumption of 608 W (819 W peak), and a volume of 470 liters which would well fit on a satellite to be launched with a Soyuz rocket, as system studies have shown.

Thilo Schuldt; Christian Schubert; Markus Krutzik; Lluis Gesa Bote; Naceur Gaaloul; Jonas Hartwig; Holger Ahlers; Waldemar Herr; Katerine Posso-Trujillo; Jan Rudolph; Stephan Seidel; Thijs Wendrich; Wolfgang Ertmer; Sven Herrmann; André Kubelka-Lange; Alexander Milke; Benny Rievers; Emanuele Rocco; Andrew Hinton; Kai Bongs; Markus Oswald; Matthias Franz; Matthias Hauth; Achim Peters; Ahmad Bawamia; Andreas Wicht; Baptiste Ba