Powered by Deep Web Technologies
Note: This page contains sample records for the topic "microwave background cmb" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


1

Cosmic Microwave Background Project at NERSC  

NLE Websites -- All DOE Office Websites (Extended Search)

Cosmic Microwave Background Cosmic Microwave Background CMB.jpg The Cosmic Microwave Background (CMB) is relic radiation from a very early stage in the universe -- essentially a...

2

CMB  

NLE Websites -- All DOE Office Websites (Extended Search)

Hubble Diagram Hubble Diagram CMB BBN Cosmic Microwave Background One of the predictions that the Big Bang theory leads to, concerns some left over pieces that could tell us the temperature of the universe.. IF we believe that the Big Bang is how the universe began, then theorists predict that we should see a remnant microwave background. It is microwave because that is the area of the spectrum in which it is found. When we look out into space with our bare eyes, we see bright objects and a whole lot of "empty" space. However, if we examine the sky with a radio telescope, we see an almost perfect blackbody spectrum in the microwave spectrum. What is a blackbody and why is it radiating? How did we find the Cosmic Microwave Background? And can we fit a curve to the data taken for the Cosmic

3

Local microwave background radiation  

E-Print Network (OSTI)

An inquiry on a possible local origin for the Microwave Background Radiation is made. Thermal MBR photons are contained in a system called {\\it magnetic bottle} which is due to Earth magnetic field and solar wind particles, mostly electrons. Observational tests are anticipated.

Domingos S. L. Soares

2006-07-11T23:59:59.000Z

4

OBSERVATIONAL SCAN-INDUCED ARTIFICIAL COSMIC MICROWAVE BACKGROUND ANISOTROPY  

SciTech Connect

Reliably detecting the cosmic microwave background (CMB) anisotropy is of great importance in understanding the birth and evolution of the universe. One of the difficulties in CMB experiments is the domination of measured CMB anisotropy maps by the Doppler dipole moment from the motion of the antenna relative to the CMB. For each measured temperature, the expected dipole component has to be calculated separately and then subtracted from the data. A small error in dipole direction, antenna pointing direction, sidelobe pickup contamination, and/or timing synchronism can introduce a significant deviation in the dipole-cleaned CMB temperature. After a full-sky observational scan, the accumulated deviations will be structured with a pattern closely correlated with the observation pattern with artificial anisotropies, including artificial quadrupole, octupole, etc., on large scales in the final CMB map. Such scan-induced anisotropies on large scales can be predicted by the true dipole moment and observational scan scheme. Indeed, the expected scan-induced quadrupole pattern of the Wilkinson Microwave Anisotropy Probe (WMAP) mission is perfectly in agreement with the published WMAP quadrupole. With the scan strategy of the Planck mission, we predict that scan-induced anisotropies will also produce an artificially aligned quadrupole. The scan-induced anisotropy is a common problem for all sweep missions and, like the foreground emissions, has to be removed from observed maps. Without doing so, CMB maps from COBE, WMAP, and Planck are not reliable for studying the CMB anisotropy.

Liu Hao; Li Tipei, E-mail: liuhao@ihep.ac.cn, E-mail: litp@tsinghua.edu.cn [Key Laboratory of Particle Astrophysics, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing (China)

2011-05-10T23:59:59.000Z

5

Non-Gaussianity and the Cosmic Microwave Background Anisotropies  

E-Print Network (OSTI)

We review in a pedagogical way the present status of the impact of non-Gaussianity (NG) on the Cosmic Microwave Background (CMB) anisotropies. We first show how to set the initial conditions at second-order for the (gauge invariant) CMB anisotropies when some primordial NG is present. However, there are many sources of NG in CMB anisotropies, beyond the primordial one, which can contaminate the primordial signal. We mainly focus on the NG generated from the post-inflationary evolution of the CMB anisotropies at second-order in perturbation theory at large and small angular scales, such as the ones generated at the recombination epoch. We show how to derive the equations to study the second-order CMB anisotropies and provide analytical computations to evaluate their contamination to primordial NG (complemented with numerical examples). We also offer a brief summary of other secondary effects. This review requires basic knowledge of the theory of cosmological perturbations at the linear level.

N. Bartolo; S. Matarrese; A. Riotto

2010-01-22T23:59:59.000Z

6

Neural networks and separation of cosmic microwave background and astrophysical signals in sky maps  

E-Print Network (OSTI)

Maps produced by large area surveys aimed at imaging primordial fluctuations of the Cosmic Microwave Background (CMB) contain a linear mixture of signals by several astrophysical and cosmological sources (Galactic synchrotron,

C. Baccigalupi; L. Bedini; C. Burigana; G. De Zotti; A. Farusi; D. Maino; M. Maris; F. Perrotta; E. Salerno; L. Toffolatti; A. Tonazzini

2000-01-01T23:59:59.000Z

7

Extracting cosmic microwave background polarisation from satellite astrophysical maps  

E-Print Network (OSTI)

We present the application of the Fast Independent Component Analysis technique for blind component separation to polarised astrophysical emission. We study how the Cosmic Microwave Background (CMB) polarised signal, consisting of $E$ and $B$ modes, can be extracted from maps affected by substantial contamination from diffuse Galactic foregrounds and instrumental noise. We perform the analysis of all sky maps simulated accordingly to the nominal performances of the Low Frequency Instrument (LFI) aboard the Planck satellite; the sky signal is modeled as a superposition of CMB, generated by a Gaussian, nearly scale invariant cosmological perturbation spectrum, and the existing simulated polarisation templates of Galactic synchrotron. Our results indicate that the angular power spectrum of CMB $E$ modes can be recovered on all scales up to $\\ell\\simeq 1000$, corresponding to the fourth acoustic oscillation, while $B$ modes can be detected, up to their turnover at $\\ell\\simeq 100$ if cosmological tensor amplitude...

Baccigalupi, C; De Zotti, G; Smoot, G F; Burigana, C; Maino, D; Bedini, L; Salerno, E

2002-01-01T23:59:59.000Z

8

The Robinson Gravitational Wave Background Telescope (BICEP): a bolometric large angular scale CMB polarimeter  

E-Print Network (OSTI)

The Robinson Telescope (BICEP) is a ground-based millimeter-wave bolometric array designed to study the polarization of the cosmic microwave background radiation (CMB) and galactic foreground emission. Such measurements probe the energy scale of the inflationary epoch, tighten constraints on cosmological parameters, and verify our current understanding of CMB physics. Robinson consists of a 250-mm aperture refractive telescope that provides an instantaneous field-of-view of 17 degrees with angular resolution of 55 and 37 arcminutes at 100 GHz and 150 GHz, respectively. Forty-nine pair of polarization-sensitive bolometers are cooled to 250 mK using a 4He/3He/3He sorption fridge system, and coupled to incoming radiation via corrugated feed horns. The all-refractive optics is cooled to 4 K to minimize polarization systematics and instrument loading. The fully steerable 3-axis mount is capable of continuous boresight rotation or azimuth scanning at speeds up to 5 deg/s. Robinson has begun its first season of observation at the South Pole. Given the measured performance of the instrument along with the excellent observing environment, Robinson will measure the E-mode polarization with high sensitivity, and probe for the B-modes to unprecedented depths. In this paper we discuss aspects of the instrument design and their scientific motivations, scanning and operational strategies, and the results of initial testing and observations.

K. W. Yoon; P. A. R. Ade; D. Barkats; J. O. Battle; E. M. Bierman; J. J. Bock; J. A. Brevik; H. C. Chiang; A. Crites; C. D. Dowell; L. Duband; G. S. Griffin; E. F. Hivon; W. L. Holzapfel; V. V. Hristov; B. G. Keating; J. M. Kovac; C. L. Kuo; A. E. Lange; E. M. Leitch; P. V. Mason; H. T. Nguyen; N. Ponthieu; Y. D. Takahashi; T. Renbarger; L. C. Weintraub; D. Woolsey

2006-06-12T23:59:59.000Z

9

Extracting cosmic microwave background polarization from satelliteastrophysical maps  

Science Conference Proceedings (OSTI)

We present the application of the fast independent component analysis (FASTICA) technique for blind component separation to polarized astrophysical emission. We study how the cosmic microwave background (CMB) polarized signal, consisting of E and B modes, can be extracted from maps affected by substantial contamination from diffuse Galactic foreground emission and instrumental noise. We implement Monte Carlo chains varying the CMB and noise realizations in order to assess the average capabilities of the algorithm and their variance. We perform the analysis of all-sky maps simulated according to the Planck satellite capabilities, modeling the sky signal as a superposition of the CMB and of the existing simulated polarization templates of Galactic synchrotron. Our results indicate that the angular power spectrum of CMB E mode can be recovered on all scales up to lsimilar or equal to 1000, corresponding to the fourth acoustic oscillation, while the B-mode power spectrum can be detected, up to its turnover at lsimilar or equal to 100, if the ratio of tensor to scalar contributions to the temperature quadrupole exceeds 30 per cent. The power spectrum of the cross-correlation between total intensity and polarization, TE, can be recovered up to lsimilar or equal to 1200, corresponding to the seventh TE acoustic oscillation.

Baccigalpi, C.; Perrotta, F.; Zotti, G.D.; Smoot, G.F.; Burigana,C.; Maino, D.; Bedini, L.; Salerno, E.

2004-05-02T23:59:59.000Z

10

Extracting cosmic microwave background polarisation from satellite astrophysical maps  

E-Print Network (OSTI)

We present the application of the Fast Independent Component Analysis ({\\ica}) technique for blind component separation to polarized astrophysical emission. We study how the Cosmic Microwave Background (CMB) polarized signal, consisting of $E$ and $B$ modes, can be extracted from maps affected by substantial contamination from diffuse Galactic foreground emission and instrumental noise. {We implement Monte Carlo chains varying the CMB and noise realizations in order to asses the average capabilities of the algorithm and their variance.} We perform the analysis of all sky maps simulated according to the {\\sc Planck} satellite capabilities, modelling the sky signal as a superposition of the CMB and of the existing simulated polarization templates of Galactic synchrotron. Our results indicate that the angular power spectrum of CMB $E$-mode can be recovered on all scales up to $\\ell\\simeq 1000$, corresponding to the fourth acoustic oscillation, while the $B$-mode power spectrum can be detected, up to its turnover at $\\ell\\simeq 100$, if the ratio of tensor to scalar contributions to the temperature quadrupole exceeds 30%. The power spectrum of the cross correlation between total intensity and polarization, $TE$, can be recovered up to $\\ell\\simeq 1200$, corresponding to the seventh $TE$ acoustic oscillation.

C. Baccigalupi; F. Perrotta; G. De Zotti; G. F. Smoot; C. Burigana; D. Maino; L. Bedini; E. Salerno

2002-09-27T23:59:59.000Z

11

Making maps of the cosmic microwave background: The MAXIMAexample  

Science Conference Proceedings (OSTI)

This work describes cosmic microwave background (CMB) data analysis algorithms and their implementations, developed to produce a pixelized map of the sky and a corresponding pixel-pixel noise correlation matrix from time ordered data for a CMB mapping experiment. We discuss in turn algorithms for estimating noise properties from the time ordered data, techniques for manipulating the time ordered data, and a number of variants of the maximum likelihood map-making procedure. We pay particular attention to issues pertinent to real CMB data, and present ways of incorporating them within the framework of maximum likelihood map making. Making a map of the sky is shown to be not only an intermediate step rendering an image of the sky, but also an important diagnostic stage, when tests for and/or removal of systematic effects can efficiently be performed. The case under study is the MAXEMA-I data set. However, the methods discussed are expected to be applicable to the analysis of other current and forthcoming CMB experiments.

Stompor, R.; Balbi, A.; Borrill, J.D.; Ferreira, P.G.; Hanany,S.; Jaffe, A.H.; Lee, A.T.; Oh, S.; Rabii, B.; Richards, P.L.; Smoot,G.F.; Winant, C.D.; Wu, J.H.P.

2001-06-25T23:59:59.000Z

12

IS THE COSMIC MICROWAVE BACKGROUND ASYMMETRY DUE TO THE KINEMATIC DIPOLE?  

SciTech Connect

Parity violation found in the cosmic microwave background (CMB) radiation is a crucial clue for the non-standard cosmological model or the possible contamination of various foreground residuals and/or calibration of the CMB data sets. In this paper, we study the directional properties of the CMB parity asymmetry by excluding the m = 0 modes in the definition of parity parameters. We find that the preferred directions of the parity parameters coincide with the CMB kinematic dipole, which implies that the CMB parity asymmetry may be connected with the possible contamination of the residual dipole component. We also find that such tendency is not only localized at l = 2, 3, but in the extended multipole ranges up to l {approx} 22.

Naselsky, P.; Zhao, W.; Kim, J.; Chen, S. [Niels Bohr Institute and Discovery Center, Blegdamsvej 17, 2100 Copenhagen, O (Denmark)

2012-04-10T23:59:59.000Z

13

Dark energy and CMB anisotropy  

E-Print Network (OSTI)

According to the WMAP and earlier COBE observations, the Cosmic Microwave Background (CMB) anisotropy power on large angular scales appears to be significantly lower than predicted by the standard model of cosmology. We ...

Lam, Yukyam, 1982-

2004-01-01T23:59:59.000Z

14

Cosmic microwave background map-making at the petascale and beyond  

Science Conference Proceedings (OSTI)

The analysis of Cosmic Microwave Background (CMB) observations is a long-standing computational challenge, driven by the exponential growth in the size of the data sets being gathered. Since this growth is projected to continue for at least the next ... Keywords: hybrid programming, petascale computing, sparse allreduce

Rajesh Sudarsan; Julian Borrill; Christopher Cantalupo; Theodore Kisner; Kamesh Madduri; Leonid Oliker; Yili Zheng; Horst Simon

2011-05-01T23:59:59.000Z

15

CMB Optical Depth Measurements: Past, Present, Future  

E-Print Network (OSTI)

The polarization of the cosmic microwave background (CMB) is encoded with exactly the same cosmic information as the CMB's temperature anistropy. However, polarization has the additional promise of accurately probing the reionization history of the universe and potentially constraining, or detecting, the primordial background of gravitational waves produced by inflation. We demonstrate that these two CMB polarization goals are mutually compatible. A polarimeter optimized to detect the inflationary gravitational wave background signature in the polarization of the CMB is well situated to detect the signatures of realistic first-light scenarios. We also discuss current results and prospects for future CMB polarization experiments.

Brian Keating; Nathan Miller

2005-08-11T23:59:59.000Z

16

Signatures of Cosmic Strings in the Cosmic Microwave Background  

E-Print Network (OSTI)

We report a search for signatures of cosmic strings in the the Cosmic Microwave Background data from the Wilkinson Microwave Anisotropy Probe. We used a digital filter designed to search for individual cosmic strings and found no evidence for them in the WMAP CMB anisotropies to a level of $\\Delta T/T \\sim 0.29$ mK. This corresponds to an absence of cosmic strings with $ G\\mu \\ga 1.07 \\times 10^{-5}$ for strings moving with velocity $v = c/\\sqrt{2}$. Unlike previous work, this limit does not depend on an assumed string abundance. We have searched the WMAP data for evidence of a cosmic string recently reported as the CSL-1 object, and found an ``edge'' with 2$\\sigma$ significance. However, if this edge is real and produced by a cosmic string, it would have to move at velocity $\\ga$ 0.94c. We also present preliminary limits on the CMB data that will be returned by the PLANCK satellite for comparison. With the available information on the PLANCK satellite, we calculated that it would be twice as sensitive to cosmic strings as WMAP.

Amy S. Lo; Edward L. Wright

2005-03-05T23:59:59.000Z

17

Charting the New Frontier of the Cosmic Microwave Background Polarization  

E-Print Network (OSTI)

The anisotropies of the cosmic microwave background are a gold mine for cosmology and fundamental physics. ESA's Planck satellite should soon extract all information from the temperature vein but will be limited concerning the measurement of the degree of polarization of the anisotropies. This polarization information allows new independent tests of the standard cosmological paradigm, improves knowledge of cosmological parameters and last but not least is the best window available for constraining the physics of the very early universe, particularly the expected background of primordial gravitational waves. But exploiting this vein will be a challenge, since the sensitivity required is {\\em at least} 10 times better than what Planck might achieve at best, with the necessary matching level of control of all systematics effects, both instrumental and astrophysical (foregrounds). We here recall the cosmological context and the case for CMB polarization studies. We also briefly introduce the SAMPAN project, a des...

Bouchet, F R; Camus, P; Désert, F X; Piat, M; Ponthieu, N; Camus, Ph.

2005-01-01T23:59:59.000Z

18

Rydberg atom detection of the temporal coherence of cosmic microwave background radiation  

E-Print Network (OSTI)

Rydberg atoms immersed in cold blackbody radiation are shown to display long-lived quantum coherence effects on timescales of tens of picoseconds. By solving non-Markovian equations of motion with no free parameters we obtain the time evolution of the density matrix, and demonstrate that the blackbody-induced temporal coherences manifest as quantum beats in time-resolved fluorescence intensities of the Rydberg atoms. A measurable fluorescence signal can be obtained with a cold trapped ensemble of 1e8 Rydberg atoms subject to 2.7 K cosmic microwave background radiation (CMB), allowing for novel insights into previously unexamined quantum coherence properties of CMB.

Tscherbul, Timur V

2013-01-01T23:59:59.000Z

19

Rydberg atom detection of the temporal coherence of cosmic microwave background radiation  

E-Print Network (OSTI)

Rydberg atoms immersed in cold blackbody radiation are shown to display long-lived quantum coherence effects on timescales of tens of picoseconds. By solving non-Markovian equations of motion with no free parameters we obtain the time evolution of the density matrix, and demonstrate that the blackbody-induced temporal coherences manifest as decaying quantum beats in time-resolved fluorescence intensities of the Rydberg atoms. A measurable fluorescence signal can be obtained with a cold trapped ensemble of 10^8 Rydberg atoms subject to suitably amplified cosmic microwave background radiation (CMB) at 2.7 K, allowing for novel insights into previously unexamined quantum coherence properties of CMB.

Timur V. Tscherbul; Paul Brumer

2013-05-23T23:59:59.000Z

20

MAXIMA-1: A Measurement of the Cosmic Microwave BackgroundAnisotropy on angular scales of 10' to 5 degrees  

Science Conference Proceedings (OSTI)

We present a map and an angular power spectrum of the anisotropy of the cosmic microwave background (CMB) from the first flight of MAXIMA. MAXIMA is a balloon-borne experiment with an array of 16 bolometric photometers operated at 100 mK. MAXIMA observed a 124 deg region of the sky with 10' resolution at frequencies of 150, 240 and 410 GHz. The data were calibrated using in-flight measurements of the CMB dipole anisotropy. A map of the CMB anisotropy was produced from three 150 and one 240 GHz photometer without need for foreground subtractions. Analysis of this CMB map yields a power spectrum for the CMB anisotropy over the range 36 {le} {ell} {le} 785. The spectrum shows a peak with an amplitude of 78 {+-} 6 {mu}K at {ell} {approx_equal} 220 and an amplitude varying between {approx} 40 {mu}K and {approx} 50 {mu}K for 400 {approx}< {ell} {approx}< 785.

Ade, P.; Balbi, A.; Bock, J.; Borrill, J.; Boscaleri, A.; deBernardis, P.; Ferreira, P.G.; Hanany, S.; Hristov, V.V.; Jaffe, A.H.; Lange, A.E.; Lee, A.T.; Mauskopf, P.D.; Netterfield, C.B.; Oh, S.; Pascale, E.; Rabii, B.; Richards, P.L.; Smoot, G.F.; Stompor, R.; Winant,C.D.; Wu, J.H.P.

2000-10-02T23:59:59.000Z

Note: This page contains sample records for the topic "microwave background cmb" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

NERSC Continues Tradition of Cosmic Microwave Background Data...  

NLE Websites -- All DOE Office Websites (Extended Search)

Tradition of Cosmic Microwave Background Data Analysis with the Planck Cluster NERSC Continues Tradition of Cosmic Microwave Background Data Analysis with the Planck...

22

Neural networks and separation of Cosmic Microwave Background and astrophysical signals in sky maps  

E-Print Network (OSTI)

The Independent Component Analysis (ICA) algorithm is implemented as a neural network for separating signals of different origin in astrophysical sky maps. Due to its self-organizing capability, it works without prior assumptions on the signals, neither on their frequency scaling, nor on the signal maps themselves; instead, it learns directly from the input data how to separate the physical components, making use of their statistical independence. To test the capabilities of this approach, we apply the ICA algorithm on sky patches, taken from simulations and observations, at the microwave frequencies, that are going to be deeply explored in a few years on the whole sky, by the Microwave Anisotropy Probe (MAP) and by the {\\sc Planck} Surveyor Satellite. The maps are at the frequencies of the Low Frequency Instrument (LFI) aboard the {\\sc Planck} satellite (30, 44, 70 and 100 GHz), and contain simulated astrophysical radio sources, Cosmic Microwave Background (CMB) radiation, and Galactic diffuse emissions from thermal dust and synchrotron. We show that the ICA algorithm is able to recover each signal, with precision going from 10% for the Galactic components to percent for CMB; radio sources are almost completely recovered down to a flux limit corresponding to $0.7\\sigma_{CMB}$, where $\\sigma_{CMB}$ is the rms level of CMB fluctuations. The signal recovering possesses equal quality on all the scales larger then the pixel size. In addition, we show that the frequency scalings of the input signals can be partially inferred from the ICA outputs, at the percent precision for the dominant components, radio sources and CMB.

C. Baccigalupi; L. Bedini; C. Burigana; G. De Zotti; A. Farusi; D. Maino; M. Maris; F. Perrotta; E. Salerno; L. Toffolatti; A. Tonazzini

2000-02-11T23:59:59.000Z

23

Differential Microwave Radiometer and the Cosmic Microwave Background |  

Office of Science (SC) Website

Differential Differential Microwave Radiometer and the Cosmic Microwave Background Laboratory Policy and Evaluation (LPE) LPE Home Staff M&O Contracts SC Laboratory Appraisal Process Laboratory Planning Process Work for Others in the Office of Science Laboratory Directed Research and Development (LDRD) DOE's Philosophy on LDRD Frequently Asked Questions Success Stories Brochures Additional Information LDRD Program Contacts Technology Transfer DOE National Laboratories Contact Information Laboratory Policy and Evaluation U.S. Department of Energy SC-32/Forrestal Building 1000 Independence Ave., SW Washington, DC 20585 P: (202) 586-5447 F: (202) 586-3119 Success Stories Differential Microwave Radiometer and the Cosmic Microwave Background Print Text Size: A A A RSS Feeds FeedbackShare Page

24

Cosmological parameter estimation from CMB experiments  

Science Conference Proceedings (OSTI)

I review the general aspects of cosmological parameter estimation from observations of the cosmic microwave background (CMB) temperature anisotropies in the framework of inflationary adiabatic models. The most recent CMB datasets are starting to give good constraints on the relevant parameters of inflationary adiabatic models. They point toward a model consistent with the basic predictions of inflation: a nearly flat universe

Amedeo Balbi

2001-01-01T23:59:59.000Z

25

ISOTROPY IN THE TWO-POINT ANGULAR CORRELATION FUNCTION OF THE COSMIC MICROWAVE BACKGROUND  

SciTech Connect

We study the directional dependence of the angular two-point correlation function in maps of the cosmic microwave background (CMB). We propose two new statistics: one which measures the correlation of each point in the sky with a ring of points separated an angle {theta} away, and a second one that measures the missing angular correlation above 60 deg as a function of direction. Using these statistics, we find that most of the low power in cut-sky maps measured by the Wilkinson Microwave Anisotropy Probe experiment comes from unusually low contributions from the directions of the lobes of the quadrupole and the octupole. These findings may aid a future explanation of why the CMB exhibits low power at large angular scales.

Zhang, Sophie, E-mail: sophz@umich.edu [Department of Physics, University of Michigan 450 Church St, Ann Arbor, MI 48109-1040 (United States)

2012-04-01T23:59:59.000Z

26

Theoretical Overview of Cosmic Microwave Background Anisotropy  

E-Print Network (OSTI)

The theoretical basis for the prediction of anisotropies in the cosmic microwave background is very well developed. Very low amplitude density and temperature perturbations produce small gravitational effects, leading to an anisotropy that is a combination of temperature fluctuations at the surface of last scattering and gravitational redshifts both at last scattering and along the path to the observer. All of the primary anisotropy can be handled by linear perturbation theory, which allows a very accurate calculation of the predicted anisotropy from different models of the Universe.

E. L. Wright

2003-05-29T23:59:59.000Z

27

What can be learned from the lensed cosmic microwave background B-mode polarization power spectrum?  

E-Print Network (OSTI)

The effect of weak gravitational lensing on the cosmic microwave background (CMB) temperature anisotropies and polarization will provide access to cosmological information that cannot be obtained from the primary anisotropies alone. We compare the information content of the lensed B-mode polarization power spectrum, properly accounting for the non-Gaussian correlations between the power on different scales, with that of the unlensed CMB fields and the lensing potential. The latter represent the products of an (idealised) optimal analysis that exploits the lens-induced non-Gaussianity to reconstruct the fields. Compressing the non-Gaussian lensed CMB into power spectra is wasteful and leaves a tight degeneracy between the equation of state of dark energy and neutrino mass that is much stronger than in the more optimal analysis. Despite this, a power spectrum analysis will be a useful first step in analysing future B-mode polarization data. For this reason, we also consider how to extract accurate parameter constraints from the lensed B-mode power spectrum. We show with simulations that for cosmic-variance-limited measurements of the lensed B-mode power, including the non-Gaussian correlations in existing likelihood approximations gives biased parameter results. We develop a more refined likelihood approximation that performs significantly better. This new approximation should also be of more general interest in the wider context of parameter estimation from Gaussian CMB data.

Sarah Smith; Anthony Challinor; Graca Rocha

2005-11-24T23:59:59.000Z

28

LOCAL NON-GAUSSIANITY IN THE COSMIC MICROWAVE BACKGROUND THE BAYESIAN WAY  

Science Conference Proceedings (OSTI)

We introduce an exact Bayesian approach to search for non-Gaussianity of local type in cosmic microwave background (CMB) radiation data. Using simulated CMB temperature maps, the newly developed technique is compared against the conventional frequentist bispectrum estimator. Starting from the joint probability distribution, we obtain analytic expressions for the conditional probabilities of the primordial perturbations given the data, and for the level of non-Gaussianity, f{sub NL}, given the data and the perturbations. We propose Hamiltonian Monte Carlo sampling as a means to derive realizations of the primordial fluctuations from which we in turn sample f{sub NL}. Although computationally expensive, this approach allows us to construct exactly the full target posterior probability distribution. When compared to the frequentist estimator, applying the Bayesian method to Gaussian CMB maps provides consistent results. For the analysis of non-Gaussian maps, however, the error bars on f{sub NL} do not show excess variance within the Bayesian framework. This finding is of particular relevance in the light of upcoming high-precision CMB measurements obtained by the Planck satellite mission.

Elsner, Franz [Max-Planck-Institut fuer Astrophysik, Karl-Schwarzschild-Strasse 1, 85748 Garching (Germany); Wandelt, Benjamin D., E-mail: felsner@mpa-garching.mpg.d [UPMC Universite Paris 06, Institut d'Astrophysique de Paris, 98 bis, blvd Arago, 75014 Paris (France)

2010-12-01T23:59:59.000Z

29

Dark Energy and CMB  

E-Print Network (OSTI)

The American Physical Society's Division of Particles and Fields initiated a long-term planning exercise over 2012-13, with the goal of developing the community's long term aspirations. The sub-group "Dark Energy and CMB" prepared a series of papers explaining and highlighting the physics that will be studied with large galaxy surveys and cosmic microwave background experiments. This paper summarizes the findings of the other papers, all of which have been submitted jointly to the arXiv.

Dodelson, S; Abazajian, K; Carlstrom, J; Huterer, D; Jain, B; Kim, A; Kirkby, D; Lee, A; Padmanabhan, N; Rhodes, J; Weinberg, D

2013-01-01T23:59:59.000Z

30

Cosmic microwave background constraints on dark energy dynamics: analysis beyond the power spectrum  

E-Print Network (OSTI)

We consider the distribution of the non-Gaussian signal induced by weak lensing on the primary total intensity cosmic microwave background (CMB) anisotropies. Our study focuses on the three point statistics exploiting an harmonic analysis based on the CMB bispectrum. By considering the three multipoles as independent variables, we reveal a complex structure of peaks and valleys determined by the re-projection of the primordial acoustic oscillations through the lensing mechanism. We study the dependence of this system on the expansion rate at the epoch in which the weak lensing power injection is relevant, probing the dark energy equation of state at redshift corresponding to the equivalence with matter or higher ($w_\\infty$). We evaluate the impact of the bispectrum observable on the CMB capability of constraining the dark energy dynamics. We perform a maximum likelihood analysis by varying the dark energy abundance, the present equation of state $w_0$ and $w_\\infty$. We show that the projection degeneracy affecting a pure power spectrum analysis in total intensity is broken if the bispectrum is taken into account. For a Planck-like experiment, assuming nominal performance, no foregrounds or systematics, and fixing all the parameters except $w_0$, $w_\\infty$ and the dark energy abundance, a percent and ten percent precision measure of $w_0$ and $w_\\infty$ is achievable from CMB data only. These results indicate that the detection of the weak lensing signal by the forthcoming CMB probes may be relevant to gain insight into the dark energy dynamics at the onset of cosmic acceleration.

Fabio Giovi; Carlo Baccigalupi; Francesca Perrotta

2004-11-25T23:59:59.000Z

31

A SEARCH FOR COSMIC MICROWAVE BACKGROUND ANISOTROPIES ON ARCMINUTE SCALES WITH BOLOCAM  

Science Conference Proceedings (OSTI)

We have surveyed two science fields totaling 1 deg.{sup 2} with Bolocam at 2.1 mm to search for secondary Cosmic Microwave Background (CMB) anisotropies caused by the Sunyaev-Zel'dovich effect (SZE). The fields are in the Lynx and Subaru/XMM SDS1 fields. Our survey is sensitive to angular scales with an effective angular multipole of l{sub eff} = 5700 with FWHM{sub l} = 2800 and has an angular resolution of 60 arcsec FWHM. Our data provide no evidence for anisotropy. We are able to constrain the level of total astronomical anisotropy, modeled as a flat-band power in C{sub l}, with most frequent 68%, 90%, and 95% CL upper limits of 590, 760, and 830 {mu}K {sup 2} {sub CMB}. We statistically subtract the known contribution from primary CMB anisotropy, including cosmic variance, to obtain constraints on the SZE anisotropy contribution. Now including flux calibration uncertainty, our most frequent 68%, 90%, and 95% CL upper limits on a flat-band power in C{sub l} are 690, 960, and 1000 {mu}K {sup 2} {sub CMB}. When we instead employ the analytical spectrum suggested by Komatsu and Seljack in 2002, and account for the non-Gaussianity of the SZE anisotropy signal, we obtain upper limits on the average amplitude of their spectrum weighted by our transfer function of 790, 1060, and 1080 {mu}K {sup 2} {sub CMB}. We obtain a 90% CL upper limit on {sigma}{sub 8}, which normalizes the power spectrum of density fluctuations, of 1.57. These are the first constraints on anisotropy and {sigma}{sub 8} from survey data at these angular scales at frequencies near 150 GHz.

Sayers, J.; Golwala, S. R.; Rossinot, P.; Edgington, S. F.; Lange, A. E. [Division of Physics, Mathematics, and Astronomy, California Institute of Technology, Mail Code 59-33, Pasadena, CA 91125 (United States); Ade, P. A. R.; Haig, D.; Mauskopf, P. D. [Physics and Astronomy, Cardiff University, 5 The Parade, P.O. Box 913, Cardiff CF24 3YB, Wales (United Kingdom); Aguirre, J. E.; Glenn, J.; Laurent, G. T. [Center for Astrophysics and Space Astronomy and Department of Astrophysical and Planetary Sciences, University of Colorado, 389 UCB, Boulder, CO 80309 (United States); Bock, J. J.; Goldin, A.; Nguyen, H. T. [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States)], E-mail: jack@caltech.edu

2009-01-10T23:59:59.000Z

32

HARMONIC IN-PAINTING OF COSMIC MICROWAVE BACKGROUND SKY BY CONSTRAINED GAUSSIAN REALIZATION  

SciTech Connect

The presence of astrophysical emissions between the last scattering surface and our vantage point requires us to apply a foreground mask on cosmic microwave background (CMB) sky maps, leading to large cuts around the Galactic equator and numerous holes. Since many CMB analysis, in particular on the largest angular scales, may be performed on a whole-sky map in a more straightforward and reliable manner, it is of utmost importance to develop an efficient method to fill in the masked pixels in a way compliant with the expected statistical properties and the unmasked pixels. In this Letter, we consider the Monte Carlo simulation of a constrained Gaussian field and derive it CMB anisotropy in harmonic space, where a feasible implementation is possible with good approximation. We applied our method to simulated data, which shows that our method produces a plausible whole-sky map, given the unmasked pixels, and a theoretical expectation. Subsequently, we applied our method to the Wilkinson Microwave Anisotropy Probe foreground-reduced maps and investigated the anomalous alignment between quadrupole and octupole components. From our investigation, we find that the alignment in the foreground-reduced maps is even higher than the Internal Linear Combination map. We also find that the V-band map has higher alignment than other bands, despite the expectation that the V-band map has less foreground contamination than other bands. Therefore, we find it hard to attribute the alignment to residual foregrounds. Our method will be complementary to other efforts on in-painting or reconstructing the masked CMB data, and of great use to Planck surveyor and future missions.

Kim, Jaiseung; Naselsky, Pavel [Niels Bohr Institute and Discovery Center, Blegdamsvej 17, DK-2100 Copenhagen (Denmark); Mandolesi, Nazzareno, E-mail: jkim@nbi.dk [INAF/IASF, Istituto di Astrofisica Spaziale e Fisica Cosmica di Bologna, Istituto Nazionale di Astrofisica, via Gobetti 101, I-40129 Bologna (Italy)

2012-05-01T23:59:59.000Z

33

Hierarchical Bayesian Detection Algorithm for Early-Universe Relics in the Cosmic Microwave Background  

E-Print Network (OSTI)

A number of theoretically well-motivated additions to the standard cosmological model predict weak signatures in the form of spatially localized sources embedded in the cosmic microwave background (CMB) fluctuations. We present a hierarchical Bayesian statistical formalism and a complete data analysis pipeline for testing such scenarios. We derive an accurate approximation to the full posterior probability distribution over the parameters defining any theory that predicts sources embedded in the CMB, and perform an extensive set of tests in order to establish its validity. The approximation is implemented using a modular algorithm, designed to avoid a posteriori selection effects, which combines a candidate-detection stage with a full Bayesian model-selection and parameter-estimation analysis. We apply this pipeline to theories that predict cosmic textures and bubble collisions, extending previous analyses by using: (1) adaptive-resolution techniques, allowing us to probe features of arbitrary size, and (2) optimal filters, which provide the best possible sensitivity for detecting candidate signatures. We conclude that the WMAP 7-year data do not favor the addition of either cosmic textures or bubble collisions to the standard cosmological model, and place robust constraints on the predicted number of such sources. The expected numbers of bubble collisions and cosmic textures on the CMB sky within our detection thresholds are constrained to be fewer than 4.0 and 5.2 at 95% confidence, respectively.

Stephen M. Feeney; Matthew C. Johnson; Jason D. McEwen; Daniel J. Mortlock; Hiranya V. Peiris

2012-10-09T23:59:59.000Z

34

Measurements of Secondary Cosmic Microwave Background Anisotropies with the South Pole Telescope  

E-Print Network (OSTI)

We report cosmic microwave background (CMB) power spectrum measurements from the first 100 sq. deg. field observed by the South Pole Telescope (SPT) at 150 and 220 GHz. On angular scales where the primary CMB anisotropy is dominant, ell ~ 50 at both frequencies. We combine the 150 and 220 GHz data to remove the majority of the point source power, and use the point source subtracted spectrum to detect Sunyaev-Zel'dovich (SZ) power at 2.6 sigma. At ell=3000, the SZ power in the subtracted bandpowers is 4.2 +/- 1.5 uK^2, which is significantly lower than the power predicted by a fiducial model using WMAP5 cosmological parameters. This discrepancy may suggest that contemporary galaxy cluster models overestimate the thermal pressure of intracluster gas. Alternatively, this result can be interpreted as evidence for lower values of sigma8. When combined with an estimate of the kinetic SZ contribution, the measured SZ amplitude shifts sigma8 from the primary CMB anisotropy derived constraint of 0.794 +/- 0.028 down t...

Lueker, M; Schaffer, K K; Zahn, O; Ade, P A R; Aird, K A; Benson, B A; Bleem, L E; Carlstrom, J E; Chang, C L; Cho, H M; Crawford, T M; Crites, A T; de Haan, T; Dobbs, M A; George, E M; Hall, N R; Halverson, N W; Holder, G P; Holzapfel, W L; Hrubes, J D; Joy, M; Keisler, R; Knox, L; Lee, A T; Leitch, E M; McMahon, J J; Mehl, J; Meyer, S S; Mohr, J J; Montroy, T E; Padin, S; Plagge, T; Pryke, C; Ruhl, J E; Shaw, L; Shirokoff, E; Spieler, H G; Staniszewski, Z; Stark, A A; Vanderlinde, K; Vieira, J D; Williamson, R

2009-01-01T23:59:59.000Z

35

MADmap: A Massively Parallel Maximum-Likelihood Cosmic Microwave Background Map-Maker  

SciTech Connect

MADmap is a software application used to produce maximum-likelihood images of the sky from time-ordered data which include correlated noise, such as those gathered by Cosmic Microwave Background (CMB) experiments. It works efficiently on platforms ranging from small workstations to the most massively parallel supercomputers. Map-making is a critical step in the analysis of all CMB data sets, and the maximum-likelihood approach is the most accurate and widely applicable algorithm; however, it is a computationally challenging task. This challenge will only increase with the next generation of ground-based, balloon-borne and satellite CMB polarization experiments. The faintness of the B-mode signal that these experiments seek to measure requires them to gather enormous data sets. MADmap is already being run on up to O(1011) time samples, O(108) pixels and O(104) cores, with ongoing work to scale to the next generation of data sets and supercomputers. We describe MADmap's algorithm based around a preconditioned conjugate gradient solver, fast Fourier transforms and sparse matrix operations. We highlight MADmap's ability to address problems typically encountered in the analysis of realistic CMB data sets and describe its application to simulations of the Planck and EBEX experiments. The massively parallel and distributed implementation is detailed and scaling complexities are given for the resources required. MADmap is capable of analysing the largest data sets now being collected on computing resources currently available, and we argue that, given Moore's Law, MADmap will be capable of reducing the most massive projected data sets.

Cantalupo, Christopher; Borrill, Julian; Jaffe, Andrew; Kisner, Theodore; Stompor, Radoslaw

2009-06-09T23:59:59.000Z

36

MAXIMA: an experiment to measure temperature anisotropy in the cosmic microwave background  

Science Conference Proceedings (OSTI)

We describe the MAXIMA experiment, a balloon-borne measurement designed to map temperature anisotropy in the Cosmic Microwave Background (CMB) from l=80 to l=800. The experiment consists of a 1.3 m diameter off-axis Gregorian telescope and a receiver with a 16 element array of bolometers cooled to 100 mK. The frequency bands are centered at 150, 240, and 410 GHz. The 10{sup {prime}} FWHM beam sizes are well matched to the scale of acoustic peaks expected in the angular power spectrum of the CMB. The first flight of the experiment in its full configuration was launched in August 1998. A 122 deg{sup 2} map of the sky was made near the Draco constellation during the 7 hour flight in a region of extremely low galactic dust contamination. This map covers 0.3{percent} of the sky and has 3200 independent beamsize pixels. We describe the MAXIMA instrument and its performance during the recent flight. {copyright} {ital 1999 American Institute of Physics.}

Lee, A.T.; Balbi, A.; Borrill, J.; Jaffe, A.H.; Oh, S.; Rabii, B.; Richards, P.L.; Smoot, G.F.; Winant, C.D. [Center for Particle Astrophysics, 301 LeConte Hall, University of California, Berkeley, California 94720 (United States); Lee, A.T.; Jaffe, A.H.; Rabii, B.; Richards, P.L.; Smoot, G.F.; Winant, C.D. [Department of Physics, University of California, Berkeley, California 94720 (United States); Ade, P.; Hristov, V.; Lange, A.E.; Pascale, E. [Queen Mary and Westfield College, London (United Kingdom); Balbi, A.; Borrill, J. [Lawrence Berkeley National Laboratory, University of California, Berkeley, California 94720 (United States); Bock, J.; Crill, B.P.; Smoot, G.F. [Department of Physics, California Institute of Technology, Pasadena, California 91125 (United States); Bock, J.; Del Castillo, H. [Jet Propulsion Laboratory, Pasadena, California 91125 (United States); Boscaleri, A. [IROE-CNR, Firenze (Italy); De Bernardis, P. [Dipartimento di Fisica, Universita La Sapienza, Roma (Italy); Ferreira, P. [CERN, Geneva (Switzerland); Ganga, K. [IPAC, Pasadena, California 91125 (United States); Hanany, S. [School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455 (United States); Mauskopf, P. [University of Massachusetts, Amhurst, Massachusetts 01003 (United States); Netterfield, C.B. [Department of Physics, University of Toronto, Toronto (Canada); Ruhl, J. [Department of Physics, University of California, Santa Barbara, California 93106 (United States)

1999-05-01T23:59:59.000Z

37

MAXIMUM LIKELIHOOD ANALYSIS OF SYSTEMATIC ERRORS IN INTERFEROMETRIC OBSERVATIONS OF THE COSMIC MICROWAVE BACKGROUND  

SciTech Connect

We investigate the impact of instrumental systematic errors in interferometric measurements of the cosmic microwave background (CMB) temperature and polarization power spectra. We simulate interferometric CMB observations to generate mock visibilities and estimate power spectra using the statistically optimal maximum likelihood technique. We define a quadratic error measure to determine allowable levels of systematic error that does not induce power spectrum errors beyond a given tolerance. As an example, in this study we focus on differential pointing errors. The effects of other systematics can be simulated by this pipeline in a straightforward manner. We find that, in order to accurately recover the underlying B-modes for r = 0.01 at 28 < l < 384, Gaussian-distributed pointing errors must be controlled to 0. Degree-Sign 7 root mean square for an interferometer with an antenna configuration similar to QUBIC, in agreement with analytical estimates. Only the statistical uncertainty for 28 < l < 88 would be changed at {approx}10% level. With the same instrumental configuration, we find that the pointing errors would slightly bias the 2{sigma} upper limit of the tensor-to-scalar ratio r by {approx}10%. We also show that the impact of pointing errors on the TB and EB measurements is negligibly small.

Zhang Le; Timbie, Peter [Department of Physics, University of Wisconsin, Madison, WI 53706 (United States); Karakci, Ata; Korotkov, Andrei; Tucker, Gregory S. [Department of Physics, Brown University, 182 Hope Street, Providence, RI 02912 (United States); Sutter, Paul M.; Wandelt, Benjamin D. [Department of Physics, 1110 W Green Street, University of Illinois at Urbana-Champaign, Urbana, IL 61801 (United States); Bunn, Emory F., E-mail: lzhang263@wisc.edu [Physics Department, University of Richmond, Richmond, VA 23173 (United States)

2013-06-01T23:59:59.000Z

38

HOT AND COLD SPOT COUNTS AS PROBES OF NON-GAUSSIANITY IN THE COSMIC MICROWAVE BACKGROUND  

SciTech Connect

We introduce the numbers of hot and cold spots, n{sub h} and n{sub c} , of excursion sets of the cosmic microwave background (CMB) temperature anisotropy maps as statistical observables that can discriminate different non-Gaussian models. We numerically compute them from simulations of non-Gaussian CMB temperature fluctuation maps. The first kind of non-Gaussian model we study is the local type primordial non-Gaussianity. The second kind of model has some specific form of the probability distribution function from which the temperature fluctuation value at each pixel is drawn, obtained using HEALPIX. We find the characteristic non-Gaussian deviation shapes of n{sub h} and n{sub c} , which is distinct for each of the models under consideration. We further demonstrate that n{sub h} and n{sub c} carry additional information compared to the genus, which is just their linear combination, making them valuable additions to the Minkowski Functionals in constraining non-Gaussianity.

Chingangbam, Pravabati [Indian Institute of Astrophysics, Koramangala II Block, Bangalore 560034 (India); Park, Changbom [Korea Institute for Advanced Study, 85 Hoegiro, Dongdaemun-gu, Seoul 130-722 (Korea, Republic of); Yogendran, K. P. [Indian Institute for Science Education and Research, Mohali (India); Van de Weygaert, Rien, E-mail: prava@iiap.res.in, E-mail: cbp@kias.re.kr, E-mail: pattag@gmail.com, E-mail: weygaert@astro.rug.nl [Kapteyn Astronomical Institute, University of Groningen, P.O. Box 800, 9747 AV Groningen (Netherlands)

2012-08-20T23:59:59.000Z

39

BAYESIAN NOISE ESTIMATION FOR NON-IDEAL COSMIC MICROWAVE BACKGROUND EXPERIMENTS  

Science Conference Proceedings (OSTI)

We describe a Bayesian framework for estimating the time-domain noise covariance of cosmic microwave background (CMB) observations, typically parameterized in terms of a 1/f frequency profile. This framework is based on the Gibbs sampling algorithm, which allows for exact marginalization over nuisance parameters through conditional probability distributions. In this paper, we implement support for gaps in the data streams and marginalization over fixed time-domain templates, and also outline how to marginalize over confusion from CMB fluctuations, which may be important for high signal-to-noise experiments. As a by-product of the method, we obtain proper constrained realizations, which themselves can be useful for map making. To validate the algorithm, we demonstrate that the reconstructed noise parameters and corresponding uncertainties are unbiased using simulated data. The CPU time required to process a single data stream of 100,000 samples with 1000 samples removed by gaps is 3 s if only the maximum posterior parameters are required, and 21 s if one also wants to obtain the corresponding uncertainties by Gibbs sampling.

Wehus, I. K. [Theoretical Physics, Imperial College London, London SW7 2AZ (United Kingdom); Naess, S. K.; Eriksen, H. K., E-mail: i.k.wehus@fys.uio.no, E-mail: sigurdkn@astro.uio.no, E-mail: h.k.k.eriksen@astro.uio.no [Institute of Theoretical Astrophysics, University of Oslo, P.O. Box 1029, Blindern, N-0315 Oslo (Norway)

2012-03-01T23:59:59.000Z

40

Cyclotron emission effect on CMB spectral distortions  

E-Print Network (OSTI)

We investigated the role of the cyclotron emission (CE) associated to cosmic magnetic fields (MF) on the evolution of cosmic microwave background (CMB) spectral distortions. We computed the photon and energy injection rates by including spontaneous and stimulated emission and absorption. These CE rates have been compared with those of bremsstrahlung (BR) and double Compton scattering (DC), for realistic CMB distorted spectra at various cosmic epochs. For reasonable MF strengths we found that the CE contribution to the evolution of the CMB spectrum is much smaller than the BR and DC contributions. The constraints on the energy exchanges at various redshifts can be then derived, under quite general assumptions, by considering only Compton scattering (CS), BR, and DC, other than the considered dissipation process. Upper limits to the CMB polarization degree induced by CE have been estimated.

Carlo Burigana; Andrea Zizzo

2006-01-12T23:59:59.000Z

Note: This page contains sample records for the topic "microwave background cmb" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

ARE THERE ECHOES FROM THE PRE-BIG-BANG UNIVERSE? A SEARCH FOR LOW-VARIANCE CIRCLES IN THE COSMIC MICROWAVE BACKGROUND SKY  

SciTech Connect

In a recent analysis of Wilkinson Microwave Anisotropy Probe (WMAP) seven-year temperature maps, Gurzadyan and Penrose claim to find concentric circular patterns in the sky with anomalously low variances. These circles are presented as observational evidence for violent processes in a universe preceding our big bang as predicted by Penrose's Conformal Cyclic Cosmology. We reassess the statistical significance of the detection of the claimed concentric low-variance circles by comparing the WMAP data with Monte Carlo simulations of the cosmic microwave background (CMB) sky plus realistic modeling of WMAP's anisotropic noise. We find no anomaly in the variances compared with the {Lambda}CDM cosmological model. The observed variances in the data are consistent with a Gaussian CMB sky as predicted by the inflationary cosmology model at better than 3{sigma}.

Hajian, Amir, E-mail: ahajian@cita.utoronto.ca [Canadian Institute for Theoretical Astrophysics, University of Toronto, Toronto, ON M5S 3H8 (Canada)

2011-10-20T23:59:59.000Z

42

Adapted method for separating kinetic SZ signal from primary CMB fluctuations  

Science Conference Proceedings (OSTI)

In this first attempt to extract amap of the kinetic Sunyaev-Zel'dovich (KSZ) temperature fluctuations from the cosmic microwave background (CMB) anisotropies, we use a method which is based on simple and minimal assumptions. We first focus on the intrinsic ... Keywords: cosmic microwave background, data analysis

Olivier Forni; Nabila Aghanim

2005-01-01T23:59:59.000Z

43

A MEASUREMENT OF SECONDARY COSMIC MICROWAVE BACKGROUND ANISOTROPIES WITH TWO YEARS OF SOUTH POLE TELESCOPE OBSERVATIONS  

SciTech Connect

We present the first three-frequency South Pole Telescope (SPT) cosmic microwave background (CMB) power spectra. The band powers presented here cover angular scales 2000 < l < 9400 in frequency bands centered at 95, 150, and 220 GHz. At these frequencies and angular scales, a combination of the primary CMB anisotropy, thermal and kinetic Sunyaev-Zel'dovich (SZ) effects, radio galaxies, and cosmic infrared background (CIB) contributes to the signal. We combine Planck/HFI and SPT data at 220 GHz to constrain the amplitude and shape of the CIB power spectrum and find strong evidence for nonlinear clustering. We explore the SZ results using a variety of cosmological models for the CMB and CIB anisotropies and find them to be robust with one exception: allowing for spatial correlations between the thermal SZ effect and CIB significantly degrades the SZ constraints. Neglecting this potential correlation, we find the thermal SZ power at 150 GHz and l = 3000 to be 3.65 {+-} 0.69 {mu}K{sup 2}, and set an upper limit on the kinetic SZ power to be less than 2.8 {mu}K{sup 2} at 95% confidence. When a correlation between the thermal SZ and CIB is allowed, we constrain a linear combination of thermal and kinetic SZ power: D{sup tSZ}{sub 3000} + 0.5D{sub 3000}{sup kSZ} = 4.60 {+-} 0.63 {mu}K{sup 2}, consistent with earlier measurements. We use the measured thermal SZ power and an analytic, thermal SZ model calibrated with simulations to determine {sigma}{sub 8} = 0.807 {+-} 0.016. Modeling uncertainties involving the astrophysics of the intracluster medium rather than the statistical uncertainty in the measured band powers are the dominant source of uncertainty on {sigma}{sub 8}. We also place an upper limit on the kinetic SZ power produced by patchy reionization; a companion paper uses these limits to constrain the reionization history of the universe.

Reichardt, C. L.; George, E. M.; Holzapfel, W. L. [Department of Physics, University of California, Berkeley, CA 94720 (United States); Shaw, L. [Department of Physics, Yale University, P.O. Box 208210, New Haven, CT 06520-8120 (United States); Zahn, O. [Berkeley Center for Cosmological Physics, Department of Physics, University of California, and Lawrence Berkeley National Labs, Berkeley, CA 94720 (United States); Aird, K. A. [University of Chicago, 5640 South Ellis Avenue, Chicago, IL 60637 (United States); Benson, B. A.; Bleem, L. E.; Carlstrom, J. E.; Chang, C. L.; Crawford, T. M.; Crites, A. T.; Hoover, S. [Kavli Institute for Cosmological Physics, University of Chicago, 5640 South Ellis Avenue, Chicago, IL 60637 (United States); Cho, H. M. [NIST Quantum Devices Group, 325 Broadway Mailcode 817.03, Boulder, CO 80305 (United States); De Haan, T.; Dobbs, M. A.; Dudley, J.; Holder, G. P. [Department of Physics, McGill University, 3600 Rue University, Montreal, Quebec H3A 2T8 (Canada); Halverson, N. W. [Department of Astrophysical and Planetary Sciences and Department of Physics, University of Colorado, Boulder, CO 80309 (United States); Hou, Z., E-mail: cr@bolo.berkeley.edu [Department of Physics, University of California, One Shields Avenue, Davis, CA 95616 (United States); and others

2012-08-10T23:59:59.000Z

44

Polarization of the Cosmic Microwave Background from Non-Uniform Reionization  

E-Print Network (OSTI)

We study the signal in the Cosmic Microwave Background (CMB) polarization anisotropy resulting from patchy reionization. It is well known that the primordial polarization of the CMB is very sensitive to the details of reionization. Combining a semi-analytic model of galaxy formation, in which the optical depth to the reionization epoch is in the range 0.014 to 0.048, with a high resolution N-body simulation we find that reionization generates a peak with amplitude 0.05~0.15 \\mu K at large angular scales. The position of this peak reveals the size of the horizon at reionization, whilst its amplitude is a measure of the optical depth to reionization. On small scales, ionized patches prior to full reionization create a second order polarization signal due to the coupling of the free electron density fluctuation with the quadrupole moment of the temperature anisotropy. Careful study reveals that the coupling generates the same power spectra for electric and magnetic modes, whose amplitudes of polarization anisotropies from this process are predicted to be ~10nK. The amplitude depends strongly on the total baryon density $\\Omega_b$ and on the spatial correlations of the free electron density in the ionized regions, and weakly on the fraction of ionizing photons able to escape their source galaxy, $f_{esc}$. The first- and second-order signals are therefore sensitive to the details of how the reionization occurred. Detection of these signals will place important constraints on the reionization history of the Universe.

Guo-Chin Liu; Naoshi Sugiyama; Andrew J. Benson; C. G. Lacey; Adi Nusser

2001-01-22T23:59:59.000Z

45

Imprint of Sterile Neutrinos in the Cosmic Microwave Background Radiation  

E-Print Network (OSTI)

The existence of low-mass sterile neutrinos is suggested by the current status of solar and atmospheric neutrinos together with the LSND experiment. In typical four-flavor scenarios, neutrinos would contribute to a cosmic hot dark matter component and to an increased radiation content at the epoch of matter-radiation equality. These effects leave their imprint in sky maps of the cosmic microwave background radiation (CMBR) and may thus be detectable with the precision measurements of the upcoming MAP and PLANCK missions.

Steen Hannestad; Georg Raffelt

1998-05-17T23:59:59.000Z

46

A detection of bright features in the microwave background  

E-Print Network (OSTI)

We report the characterization of bright, compact features in the cosmic microwave background radiation (CMBR) detected during the June 1992 and June 1994 balloon flights of the Medium Scale Anisotropy Measurement (MSAM1-92 and MSAM1-94, respectively). Spectral flux densities are determined for each feature at 5.7, 9.3, and 16.5 cm^{-1}. No viable counterparts for these features were found in source catalogs at 5 GHz or at 100 \\mum. The measured spectrum of each feature is consistent with a temperature fluctuation in the CMBR. The existence of these features is consistent with adiabatic fluctuation models of anisotropy in the CMBR.

Kowitt, M S; Cottingham, D A; Fixsen, D J; Inman, C A; Meyer, S; Page, L A; Puchalla, J L; Ruhl, J E; Silverberg, R F

1996-01-01T23:59:59.000Z

47

Central symmetry and antisymmetry of the microwave background inhomogeneities on Wilkinson Microwave Anisotropy Probe maps  

E-Print Network (OSTI)

We performed a visual and numeric analysis of the deviation of the microwave background temperature on WMAP maps. We proved that the microwave background inhomogeneities possess the property of the central symmetry resulting from the two kinds of central symmetry of the opposite signs. After the computer modeling we have established the relation between the coefficient of the central symmetry and the values of the symmetrical and antisymmetrical components of the deviation of the temperature. The obtained distribution of the symmetry coefficient on the map of the celestial sphere in Mollweide projection testifies on a contribution of both kinds of central symmetry which is approximately equal on the average in absolute magnitude but opposite by sign and where one kind of the central symmetry prevails on some sections of the celestial sphere and another kind - on the others. The average resulting value of the symmetry coefficient on the sections with angular measures less than 15-200 varies within the range fr...

Kudriavtcev, Iurii

2010-01-01T23:59:59.000Z

48

PROBING THE INFLATON: SMALL-SCALE POWER SPECTRUM CONSTRAINTS FROM MEASUREMENTS OF THE COSMIC MICROWAVE BACKGROUND ENERGY SPECTRUM  

Science Conference Proceedings (OSTI)

In the early universe, energy stored in small-scale density perturbations is quickly dissipated by Silk damping, a process that inevitably generates {mu}- and y-type spectral distortions of the cosmic microwave background (CMB). These spectral distortions depend on the shape and amplitude of the primordial power spectrum at wavenumbers k {approx}window functions that account for the effects of thermalization and dissipation physics. We show that COBE/FIRAS places a robust upper limit on the amplitude of the small-scale power spectrum. This limit is about three orders of magnitude stronger than the one derived from primordial black holes in the same scale range. Furthermore, this limit could be improved by another three orders of magnitude with PIXIE, potentially opening up a new window to early universe physics. To illustrate the power of these constraints, we consider several generic models for the small-scale power spectrum predicted by different inflation scenarios, including running-mass inflation models and inflation scenarios with episodes of particle production. PIXIE could place very tight constraints on these scenarios, potentially even ruling out running-mass inflation models if no distortion is detected. We also show that inflation models with sub-Planckian field excursion that generate detectable tensor perturbations should simultaneously produce a large CMB spectral distortion, a link that could potentially be established with PIXIE.

Chluba, Jens; Erickcek, Adrienne L.; Ben-Dayan, Ido, E-mail: jchluba@cita.utoronto.ca [Canadian Institute for Theoretical Astrophysics, 60 St. George Street, Toronto, Ontario M5S 3H8 (Canada)

2012-10-20T23:59:59.000Z

49

CMB Observational Techniques and Recent Results  

E-Print Network (OSTI)

The Cosmic Microwave Background (CMB) consists of photons that were last created about 2 months after the Big Bang, and last scattered about 380,000 years after the Big Bang. The spectrum of the CMB is very close to a blackbody at 2.725 K and upper limits on any deviations of the CMB from a blackbody place strong constraints on energy transfer between the CMB and matter at all redshifts less than 2,000,000. The CMB is very nearly isotropic, but a dipole anisotropy of +/-3.346(17) mK shows that the Solar System barycenter is moving at 368+/-2 km/sec relative to the observable Universe. The dipole corresponds to a spherical harmonic index l=1. The higher indices l geq 2 indicate intrinsic inhomogeneities in the Universe that existed at the time of last scattering. While the photons have traveled freely only since the time of last scattering, the inhomogeneities traced by the CMB photons have been in place since the inflationary epoch only 10^{-35} sec after the Big Bang. These intrinsic anisotropies are much smaller in amplitude than the dipole anisotropy, with Delta T leq 100 microK. Electron scattering of the anisotropic radiation field produces an anisotropic linear polarization in the CMB with amplitudes less than 5 microK. Detailed studies of the angular power spectrum of the temperature and linear polarization anisotropies have yielded precise values for many cosmological parameters. This paper will discuss the techniques necessary to measure signals that are 100 million times smaller than the emission from the instrument and briefly describe results from experiments up to WMAP.

E. L. Wright

2003-12-31T23:59:59.000Z

50

COSMIC MICROWAVE BACKGROUND CONSTRAINTS OF DECAYING DARK MATTER PARTICLE PROPERTIES  

SciTech Connect

If a component of cosmological dark matter is made up of massive particles-such as sterile neutrinos-that decay with cosmological lifetime to emit photons, the reionization history of the universe would be affected, and cosmic microwave background anisotropies can be used to constrain such a decaying particle model of dark matter. The optical depth depends rather sensitively on the decaying dark matter particle mass m{sub dm}, lifetime {tau}{sub dm}, and the mass fraction of cold dark matter f that they account for in this model. Assuming that there are no other sources of reionization and using the Wilkinson Microwave Anisotropy Probe 7-year data, we find that 250 eV {approx}< m{sub dm} {approx}< 1 MeV, whereas 2.23 Multiplication-Sign 10{sup 3} yr {approx}< {tau}{sub dm}/f {approx}< 1.23 Multiplication-Sign 10{sup 18} yr. The best-fit values for m{sub dm} and {tau}{sub dm}/f are 17.3 keV and 2.03 Multiplication-Sign 10{sup 16} yr, respectively.

Yeung, S.; Chan, M. H.; Chu, M.-C., E-mail: mcchu@phy.cuhk.edu.hk [Department of Physics and Institute of Theoretical Physics, Chinese University of Hong Kong, Shatin, New Territories (Hong Kong)

2012-08-20T23:59:59.000Z

51

SECOND SEASON QUIET OBSERVATIONS: MEASUREMENTS OF THE COSMIC MICROWAVE BACKGROUND POLARIZATION POWER SPECTRUM AT 95 GHz  

Science Conference Proceedings (OSTI)

The Q/U Imaging ExperimenT (QUIET) has observed the cosmic microwave background (CMB) at 43 and 95 GHz. The 43 GHz results have been published in a previous paper, and here we report the measurement of CMB polarization power spectra using the 95 GHz data. This data set comprises 5337 hr of observations recorded by an array of 84 polarized coherent receivers with a total array sensitivity of 87 {mu}K{radical}s. Four low-foreground fields were observed, covering a total of {approx}1000 deg{sup 2} with an effective angular resolution of 12.'8, allowing for constraints on primordial gravitational waves and high signal-to-noise measurements of the E-modes across three acoustic peaks. The data reduction was performed using two independent analysis pipelines, one based on a pseudo-C {sub l} (PCL) cross-correlation approach, and the other on a maximum-likelihood (ML) approach. All data selection criteria and filters were modified until a predefined set of null tests had been satisfied before inspecting any non-null power spectrum. The results derived by the two pipelines are in good agreement. We characterize the EE, EB, and BB power spectra between l = 25 and 975 and find that the EE spectrum is consistent with {Lambda}CDM, while the BB power spectrum is consistent with zero. Based on these measurements, we constrain the tensor-to-scalar ratio to r = 1.1{sup +0.9} {sub -0.8} (r pipeline, and r = 1.2{sup +0.9} {sub -0.8} (r pipeline. In one of the fields, we find a correlation with the dust component of the Planck Sky Model, though the corresponding excess power is small compared to statistical errors. Finally, we derive limits on all known systematic errors, and demonstrate that these correspond to a tensor-to-scalar ratio smaller than r = 0.01, the lowest level yet reported in the literature.

Araujo, D.; Dumoulin, R. N.; Newburgh, L. B.; Zwart, J. T. L. [Department of Physics and Columbia Astrophysics Laboratory, Columbia University, New York, NY 10027 (United States); Bischoff, C.; Brizius, A.; Buder, I.; Kusaka, A. [Kavli Institute for Cosmological Physics, Department of Physics, Enrico Fermi Institute, The University of Chicago, Chicago, IL 60637 (United States); Chinone, Y. [High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Cleary, K.; Reeves, R. [Cahill Center for Astronomy and Astrophysics, California Institute of Technology, 1200 E. California Blvd M/C 249-17, Pasadena, CA 91125 (United States); Monsalve, R.; Bustos, R. [Department of Physics, University of Miami, 1320 Campo Sano Drive, Coral Gables, FL 33146 (United States); Naess, S. K.; Eriksen, H. K. [Institute of Theoretical Astrophysics, University of Oslo, P.O. Box 1029 Blindern, NO-0315 Oslo (Norway); Wehus, I. K. [Department of Astrophysics, University of Oxford, Keble Road, Oxford OX1 3RH (United Kingdom); Bronfman, L. [Departamento de Astronomia, Universidad de Chile, Casilla 36-D, Santiago (Chile); Church, S. E. [Kavli Institute for Particle Astrophysics and Cosmology and Department of Physics, Stanford University, Varian Physics Building, 382 Via Pueblo Mall, Stanford, CA 94305 (United States); Dickinson, C. [Jodrell Bank Centre for Astrophysics, Alan Turing Building, School of Physics and Astronomy, The University of Manchester, Oxford Road, Manchester M13 9PL (United Kingdom); Gaier, T., E-mail: ibuder@uchicago.edu [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States); Collaboration: QUIET Collaboration; and others

2012-12-01T23:59:59.000Z

52

PRIMORDIAL GRAVITATIONAL WAVE DETECTABILITY WITH DEEP SMALL-SKY COSMIC MICROWAVE BACKGROUND EXPERIMENTS  

SciTech Connect

We use the Bayesian estimation on direct T - Q - U cosmic microwave background (CMB) polarization maps to forecast errors on the tensor-to-scalar power ratio r, and hence on primordial gravitational waves, as a function of sky coverage f{sub sky}. This map-based likelihood filters the information in the pixel-pixel space into the optimal combinations needed for r detection for cut skies, providing enhanced information over a first-step linear separation into a combination of E, B, and mixed modes, and ignoring the latter. With current computational power and for typical resolutions appropriate for r detection, the large matrix inversions required are accurate and fast. Our simulations explore two classes of experiments, with differing bolometric detector numbers, sensitivities, and observational strategies. One is motivated by a long duration balloon experiment like Spider, with pixel noise {proportional_to}{radical}(f{sub sky}) for a specified observing period. This analysis also applies to ground-based array experiments. We find that, in the absence of systematic effects and foregrounds, an experiment with Spider-like noise concentrating on f{sub sky} {approx} 0.02-0.2 could place a 2{sigma}{sub r} Almost-Equal-To 0.014 boundary ({approx}95% confidence level), which rises to 0.02 with an l-dependent foreground residual left over from an assumed efficient component separation. We contrast this with a Planck-like fixed instrumental noise as f{sub sky} varies, which gives a Galaxy-masked (f{sub sky} = 0.75) 2{sigma}{sub r} Almost-Equal-To 0.015, rising to Almost-Equal-To 0.05 with the foreground residuals. Using as the figure of merit the (marginalized) one-dimensional Shannon entropy of r, taken relative to the first 2003 WMAP CMB-only constraint, gives -2.7 bits from the 2012 WMAP9+ACT+SPT+LSS data, and forecasts of -6 bits from Spider (+ Planck); this compares with up to -11 bits for CMBPol, COrE, and PIXIE post-Planck satellites and -13 bits for a perfectly noiseless cosmic variance limited experiment. We thus confirm the wisdom of the current strategy for r detection of deeply probed patches covering the f{sub sky} minimum-error trough with balloon and ground experiments.

Farhang, M.; Bond, J. R.; Netterfield, C. B. [Department of Astronomy and Astrophysics, University of Toronto, 50 St. George, Toronto, ON M5S 3H4 (Canada); Dore, O. [Canadian Institute for Theoretical Astrophysics, 60 St. George, Toronto, ON M5S 3H8 (Canada)

2013-07-01T23:59:59.000Z

53

Central symmetry and antisymmetry of the microwave background inhomogeneities on Wilkinson Microwave Anisotropy Probe maps  

E-Print Network (OSTI)

We performed a visual and numeric analysis of the deviation of the microwave background temperature on WMAP maps. We proved that the microwave background inhomogeneities possess the property of the central symmetry resulting from the two kinds of central symmetry of the opposite signs. After the computer modeling we have established the relation between the coefficient of the central symmetry and the values of the symmetrical and antisymmetrical components of the deviation of the temperature. The obtained distribution of the symmetry coefficient on the map of the celestial sphere in Mollweide projection testifies on a contribution of both kinds of central symmetry which is approximately equal on the average in absolute magnitude but opposite by sign and where one kind of the central symmetry prevails on some sections of the celestial sphere and another kind - on the others. The average resulting value of the symmetry coefficient on the sections with angular measures less than 15-200 varies within the range from -50% to +50% with some prevalence of the antisymmetry - the average coefficient of the central symmetry for the whole celestial sphere is -4 +/- 1%. (antisymmetry 4%). Small scale structure of the distribution indicates that it is the result of the combined action of the mechanisms of the central symmetry and central antisymmetry, close to 100%.

Iurii Kudriavtcev; Dmitry A. Semenov

2010-08-24T23:59:59.000Z

54

A comparative study of non-Gaussianity in ILC-7yr CMB map  

E-Print Network (OSTI)

A detection or non detection of primordial non--Gaussianity (NG) by using the cosmic microwave background radiation (CMB) is a possible way to break the degeneracy of early universe models. Since a single statistical estimator hardly can be sensitive to all possible forms of NG which may be present in the data, it is important to use different statistical estimators to study NG in CMB. Recently, two new large-angle NG indicators based on skewness and kurtosis of spherical caps or spherical cells of CMB sky have been proposed and used in both CMB data and simulated maps. Here, we make a comparative study of these two different procedures by examining the NG in the WMAP seven years ILC map. We show that the spherical cells procedure detects a higher level of NG than that obtained by the method with overlapping spherical caps.

W. A. Cardona; A. Bernui; M. J. Reboucas

2013-05-25T23:59:59.000Z

55

The evolution of CMB spectral distortions in the early Universe  

E-Print Network (OSTI)

The energy spectrum of the cosmic microwave background (CMB) allows constraining episodes of energy release in the early Universe. In this paper we revisit and refine the computations of the cosmological thermalization problem. For this purpose a new code, called CosmoTherm, was developed that allows solving the coupled photon-electron Boltzmann equation in the expanding, isotropic Universe for small spectral distortion in the CMB. We explicitly compute the shape of the spectral distortions caused by energy release due to (i) annihilating dark matter; (ii) decaying relict particles; (iii) dissipation of acoustic waves; and (iv) quasi-instantaneous heating. We also demonstrate that (v) the continuous interaction of CMB photons with adiabatically cooling non-relativistic electrons and baryons causes a negative mu-type CMB spectral distortion of DI_nu/I_nu ~ 10^{-8} in the GHz spectral band. We solve the thermalization problem including improved approximations for the double Compton and Bremsstrahlung emissivities, as well as the latest treatment of the cosmological recombination process. At redshifts z injection because of (ii) and (iv) Pixie should allow to improve existing limits, while the CMB distortions caused by the other processes seem to remain unobservable with the currently proposed sensitivities and spectral bands of Pixie.

J. Chluba; R. A. Sunyaev

2011-09-29T23:59:59.000Z

56

Microwave Emission at High Galactic Latitudes  

E-Print Network (OSTI)

We use the COBE Differential Microwave Radiometers (DMR) 4-year sky maps to model Galactic microwave emission at high latitudes (|b| > 20 deg). Cross-correlation of the DMR maps with Galactic template maps detects fluctuations in the high-latitude microwave sky brightness with the angular variation of the DIRBE far-infrared dust maps and a frequency dependence consistent with a superposition of dust and free-free emission. We find no significant correlations between the DMR maps and various synchrotron templates. On the largest angular scales (e.g., quadrupole), Galactic emission is comparable in amplitude to the anisotropy in the cosmic microwave background (CMB). The CMB quadrupole amplitude, after correction for Galactic emission, has amplitude $Q_{rms}$ = 10.7 uK with random uncertainty 3.6 uK and systematic uncertainty 7.1 uK from uncertainty in our knowledge of Galactic microwave emission.

A. Kogut; G. Hinshaw; A. J. Banday; C. L. Bennett; K. Gorski; G. F. Smoot; E. L. Wright

1996-01-12T23:59:59.000Z

57

Bayesian Inference of Polarized CMB Power Spectra from Interferometric Data  

E-Print Network (OSTI)

Detection of B-mode polarization of the cosmic microwave background (CMB) radiation is one of the frontiers of observational cosmology. Because they are an order of magnitude fainter than E-modes, it is quite a challenge to detect B-modes. Having more manageable systematics, interferometers prove to have a substantial advantage over imagers in detecting such faint signals. Here, we present a method for Bayesian inference of power spectra and signal reconstruction from interferometric data of the CMB polarization signal by using the technique of Gibbs sampling. We demonstrate the validity of the method in the flat-sky approximation for a simulation of an interferometric observation on a finite patch with incomplete uv-plane coverage, a finite beam size and a realistic noise model. With a computational complexity of O(n^{3/2}), n being the data size, Gibbs sampling provides an efficient method for analyzing upcoming cosmology observations.

Karakci, Ata; Zhang, Le; Bunn, Emory F; Korotkov, Andrei; Timbie, Peter; Tucker, Gregory S; Wandelt, Benjamin D

2012-01-01T23:59:59.000Z

58

Primordial Magnetic Field Limits from CMB Trispectrum - Scalar Modes and Planck Constraints  

E-Print Network (OSTI)

Cosmic magnetic fields are observed to be coherent on large scales and could have a primordial origin. Non-Gaussian signals in the cosmic microwave background (CMB) are generated by primordial magnetic fields as the magnetic stresses and temperature anisotropy they induce depend quadratically on the magnetic field. We compute the CMB scalar trispectrum on large angular scales, for nearly scale-invariant magnetic fields, sourced via the Sachs-Wolfe effect. The trispectra induced by magnetic energy density and by magnetic scalar anisotropic stress are found to have typical magnitudes of approximately $10^{-29}$ and $10^{-19}$, respectively. The scalar anisotropic stress trispectrum is also calculated in the flat-sky approximation and yields a similar result. Observational limits on CMB non-Gaussianity from the Planck mission data allow us to set upper limits of $B_0 \\lesssim 0.6 $ nG on the present value of the primordial cosmic magnetic field. Considering the inflationary magnetic curvature mode in the trispectrum can further tighten the magnetic field upper limit to $B_0 \\lesssim 0.05 $ nG. These sub-nanoGauss constraints from the magnetic trispectrum are the most stringent limits so far on the strength of primordial magnetic fields, on megaparsec scales, significantly better than the limits obtained from the CMB bispectrum and the CMB power spectrum.

Pranjal Trivedi; Kandaswamy Subramanian; T. R. Seshadri

2013-12-18T23:59:59.000Z

59

Needlet detection of features in the WMAP CMB sky and the impact on anisotropies and hemispherical asymmetries  

SciTech Connect

We apply spherical needlets to the Wilkinson Microwave Anisotropy Probe 5-year cosmic microwave background (CMB) data set, to search for imprints of nonisotropic features in the CMB sky. We use the needlets' localization properties to resolve peculiar features in the CMB sky and to study how these features contribute to the anisotropy power spectrum of the CMB. In addition to the now well-known 'cold spot' of the CMB map in the southern hemisphere, we also find two hot spots at greater than 99% confidence level, again in the southern hemisphere and closer to the Galactic plane. While the cold spot contributes to the anisotropy power spectrum in the multipoles between l=6 to l=33, the hot spots are found to be dominating the anisotropy power in the range between l=6 and l=18. Masking both the cold and the two hot spots results in a reduction by about 15% in the amplitude of the angular power spectrum of CMB around l=10. The resulting changes to the cosmological parameters when the power spectrum is estimated masking these features (in addition to the WMAP team's KQ85 mask) are within the 1{sigma} errors published with the WMAP mask only. We also study the asymmetry between the angular power spectra evaluated on the northern and southern hemispheres. When the features detected by needlets are masked, we find that the difference in the power, measured in terms of the anisotropy variance between l=4 and l=18, is reduced by a factor 2. We make available a mask related to needlet features for more detailed studies on asymmetries in the CMB anisotropy sky.

Pietrobon, Davide [Dipartimento di Fisica, Universita di Roma 'Tor Vergata', via della Ricerca Scientifica 1, 00133 Roma (Italy); Institute of Cosmology and Gravitation, University of Portsmouth, Mercantile House, Portsmouth PO1 2EG (United Kingdom); Center for Cosmology, University of California, Irvine, California 92697 (United States); Amblard, Alexandre; Cooray, Asantha [Center for Cosmology, University of California, Irvine, California 92697 (United States); Balbi, Amedeo [Dipartimento di Fisica, Universita di Roma 'Tor Vergata', via della Ricerca Scientifica 1, 00133 Roma (Italy); INFN Sezione di Roma 'Tor Vergata', via della Ricerca Scientifica 1, 00133 Roma (Italy); Cabella, Paolo [Dipartimento di Fisica, Universita di Roma 'Tor Vergata', via della Ricerca Scientifica 1, 00133 Roma (Italy); Marinucci, Domenico [Dipartimento di Matematica, Universita di Roma 'Tor Vergata', via della Ricerca Scientifica 1, 00133 Roma (Italy)

2008-11-15T23:59:59.000Z

60

The Cosmic Microwave Background Spectrum from the Full COBE/FIRAS Data Set  

E-Print Network (OSTI)

We have refined the analysis of the data from the FIRAS (Far InfraRed Absolute Spectrophotometer) on board the COBE (COsmic Background Explorer). The FIRAS measures the difference between the cosmic microwave background and a precise blackbody spectrum. We find new tighter upper limits on general deviations from a blackbody spectrum. The RMS deviations are less than 50 parts per million of the peak of the CMBR. For the Comptonization and chemical potential we find $|y| < 15\\times10^{-6}$ and $|\\mu| < 9\\times10^{-5}$ (95\\% CL). There are also refinements in the absolute temperature, 2.728 $\\pm$ 0.004 K (95\\% CL), and dipole direction, $(\\ell,b)=(264.14^\\circ\\pm0.30, 48.26^\\circ\\pm0.30)$ (95\\% CL), and amplitude, $3.372 \\pm 0.007$ mK (95\\% CL). All of these results agree with our previous publications.

D. J. Fixsen; E. S. Cheng; J. M. Gales; J. C. Mather; R. A. Shafer; E. L. Wright

1996-05-10T23:59:59.000Z

Note: This page contains sample records for the topic "microwave background cmb" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Removing 1/f noise stripes in cosmic microwave background anisotropy observations  

E-Print Network (OSTI)

Removal of systematic effects is crucial in present and future CMB experiments mapping large fraction of the sky. Accurate CMB measurements ask for multi-feed array instruments observing the sky with a redundant scanning strategy covering the same region of the sky on different time scales and with different detectors for a better control of systematic effects. We investigate here the capability to suppress 1/f noise features in Time Ordered Data (TOD) by using the destriping technique described in Maino et al. (1999), under realistic assumptions for crossing condition between different scan circles and sky signal fluctuations on small angular scales. We consider as working case, Planck-LFI simulated observations with few arminutes pixel size convolved with LFI beam resolutions. We also extend the analysis to high values of the knee-frequency and found a residual additional noise rms ~31% larger than the pure white noise rms at fk=1 Hz which could be a critical issue in the extraction of the CMB angular power spectrum. Furthermore we verified that destriping quality does not significantly depend on the receiver sensitivity whereas it improves proportionally to the improvement of sampling rate. Therefore given a noise level, the higher the sampling rate, the better the destriping quality.

D. Maino; C. Burigana; K. M. Gorski; N. Mandolesi; M. Bersanelli

2002-02-14T23:59:59.000Z

62

An Absolute Measurement of the Cosmic Microwave Background Radiation Temperature at 10.7 GHz  

E-Print Network (OSTI)

A balloon-borne experiment has measured the absolute temperature of the cosmic microwave background radiation (CMBR) at 10.7 GHz to be Tcmbr = 2.730 +- .014 K. The error is the quadratic sum of several systematic errors, with statistical error of less than 0.1 mK. The instrument comprises a cooled corrugated horn antenna coupled to a total-power radiometer. A cryogenic mechanical waveguide switch alternately connects the radiometer to the horn and to an internal reference load. The small measured temperature difference (load in conjunction with the use of a cold front end keeps systematic instrumental corrections small. Atmospheric and window emission are minimized by flying the instrument at 24 km altitude. A large outer ground screen and smaller inner screen shield the instrument from stray radiation from the ground and the balloon. In-flight tests constrain the magnitude of ground radiation contamination, and low level interference is monitored through observations in several narrow frequency bands.

S. T. Staggs; N. C. Jarosik; S. S. Meyer; D. T. Wilkinson

1996-09-19T23:59:59.000Z

63

Frequentist estimation of cosmological parameters from theMAXIMA-1 cosmic microwave background anisotropy data  

SciTech Connect

We use a frequentist statistical approach to set confidence intervals on the values of cosmological parameters using the MAXIMA-1 and COBE measurements of the angular power spectrum of the cosmic microwave background. We define a Deltachi (2) statistic, simulate the measurements of MAXIMA-1 and COBE, determine the probability distribution of the statistic, and use it and the data to set confidence intervals on several cosmological parameters. We compare the frequentist confidence intervals with Bayesian credible regions. The frequentist and Bayesian approaches give best estimates for the parameters that agree within 15 per cent, and confidence interval widths that agree to within 30 per cent. The results also suggest that a frequentist analysis gives slightly broader confidence intervals than a Bayesian analysis. The frequentist analysis gives values of Omega = 0.89(-0.19)(+0.26), Omega(B) h(2) =0.026(-0.011)(+0.020) and n = 1.02(-0.10)(+0.31), and the Bayesian analysis gives values of Omega = 0.98(-0.19)(+0.14) Omega(B) h(2) =0.029(-0.010)(+0.015), and n = 1.18(-0.23)(+0.10), all at the 95 per cent confidence level.

Abroe, M.E.; Balbi, A.; Borrill, J.; Bunn, E.F.; Hanany, S.; Ferreira, P.G.; Jaffe, A.H.; Lee, A.T.; Olive, K.A.; Rabii, B.; Richards,P.L.; Smoot, G.F.; Stompor, R.; Winant, C.D.; Wu, J.H.P.

2001-11-07T23:59:59.000Z

64

Producing Mega-pixel CMB Maps from Differential Radiometer Data  

E-Print Network (OSTI)

A major goal of cosmology is to obtain sensitive, high resolution maps of the Cosmic Microwave Background (CMB) anisotropy. Such maps, as would be produced by the recently proposed Microwave Anisotropy Probe (MAP), will contain a wealth of primary information about conditions in the early universe. To mitigate systematic effects when observing the microwave background, it is desirable for the raw data to be collected in differential form: as a set of temperature differences between points in the sky. However, the production of large (mega-pixel) maps from a set of temperature differences is a potentially severe computational challenge. We present a new technique for producing maps from differential radiometer data that has a computational cost that grows in the slowest possible way with increasing angular resolution and number of map pixels. The required central processor (CPU) time is proportional to the number of differential data points and the required random access memory (RAM) is proportional to the number of map pixels. We test our technique, and demonstrate its feasibility, by simulating one year of a space-borne anisotropy mission.

Edward L. Wright; Gary Hinshaw; Charles L. Bennett

1995-10-20T23:59:59.000Z

65

A Search for Cosmic Microwave Background Anisotropies on Arcminute Scales with Bolocam  

E-Print Network (OSTI)

We have surveyed two science fields totaling one square degree with Bolocam at 2.1 mm to search for secondary CMB anisotropies caused by the Sunyaev- Zel'dovich effect (SZE). The fields are in the Lynx and Subaru/XMM SDS1 fields. Our survey is sensitive to angular scales with an effective angular multipole of l_eff = 5700 with FWHM_l = 2800 and has an angular resolution of 60 arcseconds FWHM. Our data provide no evidence for anisotropy. We are able to constrain the level of total astronomical anisotropy, modeled as a flat bandpower in C_l, with frequentist 68%, 90%, and 95% CL upper limits of 590, 760, and 830 uKCMB^2. We statistically subtract the known contribution from primary CMB anisotropy, including cosmic variance, to obtain constraints on the SZE anisotropy contribution. Now including flux calibration uncertainty, our frequentist 68%, 90% and 95% CL upper limits on a flat bandpower in C_l are 690, 960, and 1000 uKCMB^2. When we instead employ the analytic spectrum suggested by Komatsu and Seljak (2002...

Sayers, J; Rossinot, P; Ade, P A R; Aguirre, J E; Bock, J J; Edgington, S F; Glenn, J; Goldin, A; Haig, D; Lange, A E; Laurent, G T; Mauskopf, P D; Nguyen, H T

2008-01-01T23:59:59.000Z

66

Tomography of the Reionization Epoch with Multifrequency CMB Observations  

E-Print Network (OSTI)

We study the constraints that future multifrequency Cosmic Microwave Background (CMB) experiments will be able to set on the metal enrichment history of the Inter Galactic Medium at the epoch of reionisation. We forecast the signal to noise ratio for the detection of the signal introduced in the CMB by resonant scattering off metals at the end of the Dark Ages. We take into account systematics associated to inter-channel calibration, PSF reconstruction errors and innacurate foreground removal. We develop an algorithm to optimally extract the signal generated by metals during reionisation and to remove accurately the contamination due to the thermal Sunyaev-Zel'dovich effect. Although demanding levels of foreground characterisation and control of systematics are required, they are very distinct from those encountered in HI-21cm studies and CMB polarization, and this fact encourages the study of resonant scattering off metals as an alternative way of conducting tomography of the reionisation epoch. An ACT-like experiment with optimistic assumtions on systematic effects, and looking at clean regions of the sky, can detect changes of 3%-12% (95% c.l.) of the OIII abundance (with respect its solar value) in the redshift range $z\\in$ [12,22], for reionization redshift $z_{\\rm re}>10$. However, for $z_{\\rm re} solar value in the redshift range $z\\in$ [5.5,9], (95% c.l.). These constraints assume that inter-channel calibration is accurate down to one part in $10^{4}$, which constitutes the most critical technical requirement of this method, but still achievable with current technology.

Carlos Hernandez-Monteagudo; Licia Verde; Raul Jimenez

2006-04-14T23:59:59.000Z

67

Multi-chroic dual-polarization bolometric detectors for studies of the Cosmic Microwave Background  

E-Print Network (OSTI)

We are developing multi-chroic antenna-coupled TES detectors for CMB polarimetry. Multi-chroic detectors increase the mapping speed per focal plane area and provide greater discrimination of polarized galactic foregrounds with no increase in weight or cryogenic cost. In each pixel, a silicon lens-coupled dual polarized sinuous antenna collects light over a two-octave frequency band. The antenna couples the broadband millimeter wave signal into microstrip transmission lines, and on-chip filter banks split the broadband signal into several frequency bands. Separate TES bolometers detect the power in each frequency band and linear polarization. We will describe the design and performance of these devices and present optical data taken with prototype pixels. Our measurements show beams with percent level ellipticity, percent level cross-polarization leakage, and partitioned bands using banks of 2, 3, and 7 filters. We will also describe the development of broadband anti-reflection coatings for the high dielectric...

Suzuki, Aritoki; Edwards, Jennifer; Engargiola, Greg; Ghribi, Adnan; Holzapfel, William; Lee, Adrian T; Meng, Xiao Fan; Myers, Michael J; O'Brient, Roger; Quealy, Erin; Rebeiz, Gabriel; Richards, Paul; Rosen, Darin; Siritanasak, Praween

2012-01-01T23:59:59.000Z

68

MAXIMA: A balloon-borne cosmic microwave backgroundexperiment  

SciTech Connect

We describe the Millimeter wave Anisotropy eXperiment IMaging Array (MAXIMA), a balloon-borne experiment which measured the temperature anisotropy of the cosmic microwave background (CMB) on angular scales of 10(minutes) to 5 degrees. MAXIMA mapped the CMB using 16 bolometric detectors in spectral bands centered at 150, 240, and 410 GHz, with 10(minutes) resolution at all frequencies. The combined receiver sensitivity to CMB anisotropy was similar to 40 mu K root s. The bolometric detectors, which were cooled to 100 mK, were a prototype of the detectors which will be used on the Planck Surveyor Satellite of the European Space Agency. Systematic parasitic contributions were controlled by using four uncorrelated spatial modulations, thorough cross-linking, multiple independent CMB observations, heavily baffled optics, and strong spectral discrimination. Pointing reconstruction was accurate to 1(minute), and absolute calibration was better than 4 percent. Two MAXIMA flights with more than 8.5 h of CMB observations have mapped a total of 300deg(2) of the sky in regions of negligible known foreground emission. MAXIMA results have been released in previous publications and shown to be consistent with the Wilkinson Microwave Anisotropy Probe. MAXIMA Imaps, power spectra, and correlation matrices are publicly available at http://cosmology.berkeley.edu/maxima.

Rabii, B.; Winant, C.D.; Collins, J.S.; Lee, A.T.; Richards,P.L.; Abroe, M.E.; Hanany, S.; Johnson, B.R.; Ade, P.; Balbi, A.; Bock,J.J.; Borrill, J.; Stompor, R.; Boscaleri, A.; Pascale, E.; de Bernardis,P.; Ferreira, P.G.; Hristov, V.V.; Lange, A.E.; Jaffe, A.H.; Netterfield,C.B.; Smoot, G.F.; Wu, J.H.P.

2004-03-03T23:59:59.000Z

69

A Search for Cosmic Microwave Background Anisotropies on Arcminute Scales with Bolocam  

E-Print Network (OSTI)

We have surveyed two science fields totaling one square degree with Bolocam at 2.1 mm to search for secondary CMB anisotropies caused by the Sunyaev- Zel'dovich effect (SZE). The fields are in the Lynx and Subaru/XMM SDS1 fields. Our survey is sensitive to angular scales with an effective angular multipole of l_eff = 5700 with FWHM_l = 2800 and has an angular resolution of 60 arcseconds FWHM. Our data provide no evidence for anisotropy. We are able to constrain the level of total astronomical anisotropy, modeled as a flat bandpower in C_l, with frequentist 68%, 90%, and 95% CL upper limits of 590, 760, and 830 uKCMB^2. We statistically subtract the known contribution from primary CMB anisotropy, including cosmic variance, to obtain constraints on the SZE anisotropy contribution. Now including flux calibration uncertainty, our frequentist 68%, 90% and 95% CL upper limits on a flat bandpower in C_l are 690, 960, and 1000 uKCMB^2. When we instead employ the analytic spectrum suggested by Komatsu and Seljak (2002), and account for the non-Gaussianity of the SZE anisotropy signal, we obtain upper limits on the average amplitude of their spectrum weighted by our transfer function of 790, 1060, and 1080 uKCMB^2. We obtain a 90% CL upper limit on sigma8, which normalizes the power spectrum of density fluctuations, of 1.57. These are the first constraints on anisotropy and sigma8 from survey data at these angular scales at frequencies near 150 GHz.

J. Sayers; S. R. Golwala; P. Rossinot; P. A. R. Ade; J. E. Aguirre; J. J. Bock; S. F. Edgington; J. Glenn; A. Goldin; D. Haig; A. E. Lange; G. T. Laurent; P. D. Mauskopf; H. T. Nguyen

2008-05-20T23:59:59.000Z

70

DIRECT MEASUREMENT OF THE ANGULAR POWER SPECTRUM OF COSMIC MICROWAVE BACKGROUND TEMPERATURE ANISOTROPIES IN THE WMAP DATA  

Science Conference Proceedings (OSTI)

The angular power spectrum of the cosmic microwave background temperature anisotropies is one of the most important characteristics in cosmology that can shed light on the properties of the universe such as its geometry and total density. Using flat sky approximation and Fourier analysis, we estimate the angular power spectrum from an ensemble of the least foreground-contaminated square patches from the Wilkinson Microwave Anisotropy Probe W and V frequency band map. This method circumvents the issue of foreground cleaning and that of breaking orthogonality in spherical harmonic analysis because we are able to mask out the bright Galactic plane region, thereby rendering a direct measurement of the angular power spectrum. We test and confirm the Gaussian statistical characteristic of the selected patches, from which the first and second acoustic peaks of the power spectrum are reproduced, and the third peak is clearly visible, albeit with some noise residual at the tail.

Chiang, Lung-Yih [Institute of Astrophysics, National Taiwan University, 1, Rooservolt Road, Taipei, Taiwan (China); Chen, Fei-Fan, E-mail: lychiang@asiaa.sinica.edu.tw [Institute of Astronomy and Astrophysics, Academia Sinica, P.O. Box 23-141, Taipei 10617, Taiwan (China)

2012-05-20T23:59:59.000Z

71

BACKGROUND  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Emergency Medical Coordination Emergency Medical Coordination Memorandum of Agreement at Brookhaven National Laboratory DOE/IG-0594 March 2003 Department of Energy Washington, DC 20585 March 3 1,2003 FROM: Inspector General SUBJECT: INFORMATION: Report on Inspection of "Emergency Medical Coordination Memorandum of Agreement at Brookhaven National Laboratory" BACKGROUND Because of possible exposure to radioactive and hazardous materials and the potential for industrial accidents at Department of Energy (DOE) sites, the Department has established formalized agreements with local emergency medical providers. These arrangements are generally documented through memoranda of agreements (MOAs). These documents detail the m u

72

Background  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Format for the one pager: Report Statement/Recommendation Format for the one pager: Report Statement/Recommendation Background Pros/Cons discussion We would like to see good drafts by noon. 3/30/01. 11 circulate them as soon as I get them in. Any questions, give me a call. 456-7874 Charlie ___ ___ _8171 DOE015-1514 Martin, Adrienne ^ From: Anderson, Margot / / Sent: Thursday, March 29, 2001 723 PM To: 'Andrew D. Lundquisltovp.eop.gov%intemet' Subject: RE: 1 spoke with Charlie and we got it fixed. Thanksl -Original Message- From: Andrew D. Lundquist@ovp.eop.gov%intemet Imailto:Andrew D. Lundquistovp.eop.gov] Sent: Thursday March 29, 2001 7:18 PM To: Anderson. Margot Cc: Kelliher, Joseph; Kolevar, Kevin; Charles M. Smthovp.egov%htemet; Juleanna FR GOovsWeovp.eop.gov%intemet 'kmurphyiosec.doc.gov%intemet 'dina.eisOdo.treas.gov%intemer;

73

Background  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Patent Rights in the New Patent Rights in the New Independent States (NIS) of the Former Soviet Union for Inventions made by NIS institutes' employeess in the course of or under agreements entered into pursuant to the Fiscal Year 1994 Foreign Operations Appropriations Act (P.L. 103- 87). W(C) 94-001 Background The dissolution of the Soviet Union and the drastic reductions in defense spending by the NIS have created an extremely difficult situation for the scientists and engineers who are responsible for the former Soviet Union's defense technology base. It is estimated that there are several tens of thousands of such scientists and engineers; they possess critical technical knowledge about weapons of mass destruction and are underemployed and undercompensated, and consequently, could contribute to

74

Background  

Office of Legacy Management (LM)

explains the potential health hazards associated with air quality related to the removal and storage of explains the potential health hazards associated with air quality related to the removal and storage of mill tailings and other contaminated materials. Background From 1942 to 1960, uranium ore was processed at the Monticello mill in southeast Utah. When the mill was closed, approximately 2.3 million cubic yards of low-level radioactive mill tailings, contaminated soil, and other miscellaneous debris remained on the site. The U.S. Department of Energy (DOE) Grand Junction Projects Office, in conjunction with the U.S. Environmental Protection Agency (EPA) and the State of Utah, is conducting the cleanup of the millsite and more than 400 area homes and businesses contaminated with mill tailings. The purpose of the cleanup is to minimize risks to the public and the

75

Cosmological constraints from the CMB and Ly-alpha forest revisited  

E-Print Network (OSTI)

The WMAP team has recently highlighted the usefulness of combining the Ly-alpha forest constraints with those from the cosmic microwave background (CMB). This combination is particularly powerful as a probe of the primordial shape of the power spectrum. Converting between the Ly-alpha forest observations and the linear mass power spectrum requires a careful treatment of nuisance parameters and modeling with cosmological simulations. We point out several issues which lead to an expansion of the errors, the two most important being the range of cosmological parameters explored in simulations and the treatment of the mean transmitted flux constraints. We employ a likelihood calculator for the current Ly-alpha data set based on an extensive 6-dimensional grid of simulations. We show that the current uncertainties in the mean transmission and the flux power spectrum define a degeneracy line in the amplitude-slope plane. The CMB degeneracy due to the primordial power spectrum shape follows a similar relation in this plane. This weakens the statistical significance of the primordial power spectrum shape constraints based on combined CMB+Ly-alpha forest analysis. Using the current data the simplest n=1 scale invariant model with dn/dln k=0 and no tensors has a Delta chi^2=4 compared to the best fitting model in which these 3 parameters are free. Current data therefore do not require relaxing these parameters to improve the fit.

Uros Seljak; Patrick McDonald; Alexey Makarov

2003-02-27T23:59:59.000Z

76

Window Functions for CMB Experiments  

E-Print Network (OSTI)

We discuss the applicability and derivation of window functions for cosmic microwave background experiments on large and intermediate angular scales. These window functions describe the response of the experiment to power in a particular mode of the fluctuation spectrum. We give general formulae, illustrated with specific examples, for the most common observing strategies.

Martin White; Mark Srednicki

1994-02-15T23:59:59.000Z

77

Determining the motion of the solar system relative to the cosmic microwave background using type Ia supernovae  

E-Print Network (OSTI)

We estimate the solar system motion relative to the cosmic microwave background using type Ia supernovae (SNe) measurements. We take into account the correlations in the error bars of the SNe measurements arising from correlated peculiar velocities. Without accounting for correlations in the peculiar velocities, the SNe data we use appear to detect the peculiar velocity of the solar system at about the 3.5 sigma level. However, when the correlations are correctly accounted for, the SNe data only detects the solar system peculiar velocity at about the 2.5 sigma level. We forecast that the solar system peculiar velocity will be detected at the 9 sigma level by GAIA and the 11 sigma level by the LSST. For these surveys we find the correlations are much less important as most of the signal comes from higher redshifts where the number density of SNe is insufficient for the correlations to be important.

Christopher Gordon; Kate Land; Anze Slosar

2007-11-27T23:59:59.000Z

78

Forecast constraints on cosmic strings from future CMB, pulsar timing and gravitational wave direct detection experiments  

E-Print Network (OSTI)

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

2012-10-10T23:59:59.000Z

79

Multiple Peaks in the Angular Power Spectrum of the CosmicMicrowave Background: Significance and Consequences for Cosmology  

Science Conference Proceedings (OSTI)

Three peaks and two dips have been detected in the power spectrum of the cosmic microwave background from the BOOMERANG experiment, at {ell} {approx} 210, 540, 840 and {ell} {approx} 420, 750, respectively. Using model-independent analyses, we find that all five features are statistically significant and we measure their location and amplitude. These are consistent with the adiabatic inflationary model. We also calculate the mean and variance of the peak and dip locations and amplitudes in a large 7-dimensional parameter space of such models, which gives good agreement with the model-independent estimates, and forecast where the next few peaks and dips should be found if the basic paradigm is correct. We test the robustness of our results by comparing Bayesian marginalization techniques on this space with likelihood maximization techniques applied to a second 7-dimensional cosmological parameter space, using an independent computational pipeline, and find excellent agreement: {Omega}{sub tot} = 1.02{sub -0.05}{sup +0.06} vs. 1.04 {+-} 0.05, {Omega}{sub b}h{sup 2} = 0.022{sub -0.003}{sup +0.004} vs. 0.019{sub -0.004}{sup +0.005}, and n{sub s} = 0.96{sub -0.09}{sup +0.10} vs. 0.90 {+-} 0.08. The deviation in primordial spectral index n{sub s} is a consequence of the strong correlation with the optical depth.

de Bernardis, P.; Ade, P.A.R.; Bock, J.J.; Bond, J.R.; Borrill,J.; Boscaleri, A.; Coble, K.; Contaldi, C.R.; Crill, B.P.; De Troia, G.; Farese, P.; Ganga, K.; Giacometti, M.; Hivon, E.; Hristov, V.V.; Iacoangeli, A.; Jaffe, A.H.; Jones, W.C.; Lange, A.E.; Martinis, L.; Masi, S.; Mason, P.; Mauskopf, P.D.; Melchiorri, A.; Montroy, T.; Netterfield, C.B.; Pascale, E.; Piacentini, F.; Pogosyan, D.; Polenta,G.; Pongetti, F.; Prunet, S.; Romeo, G.; Ruhl, J.E.; Scaramuzzi, F.

2001-05-17T23:59:59.000Z

80

Fast CMB Power Spectrum Estimation of Temperature and Polarisation with Gabor Transforms  

E-Print Network (OSTI)

We extend the analysis of Gabor transforms on a Cosmic Microwave Background (CMB) temperature map (Hansen, Gorski and Hivon 2002) to polarisation. We study the temperature and polarisation power spectra on the cut sky, the so-called pseudo power spectra. The transformation kernels relating the full-sky polarisation power spectra and the polarisation pseudo power spectra are found to be similar to the kernel for the temperature power spectrum. This fact is used to construct a fast power spectrum estimation algorithm using the pseudo power spectrum of temperature and polarisation as data vectors in a maximum likelihood approach. Using the pseudo power spectra as input to the likelihood analysis solves the problem of having to invert huge matrices which makes the standard likelihood approach infeasible.

Frode K. Hansen; Krzysztof M. Gorski

2002-07-24T23:59:59.000Z

Note: This page contains sample records for the topic "microwave background cmb" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Cosmic string induced CMB maps  

SciTech Connect

We compute maps of CMB temperature fluctuations seeded by cosmic strings using high resolution simulations of cosmic strings in a Friedmann-Robertson-Walker universe. We create full-sky, 18 deg. and 3 deg. CMB maps, including the relevant string contribution at each resolution from before recombination to today. We extract the angular power spectrum from these maps, demonstrating the importance of recombination effects. We briefly discuss the probability density function of the pixel temperatures, their skewness, and kurtosis.

Landriau, M. [Max-Planck-Institut fuer extraterrestrische Physik, Giessenbachstrasse 1, 85748 Garching (Germany); Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Centre for Mathematical Sciences, Wilberforce Road, Cambridge CB3 0WA (United Kingdom); Shellard, E. P. S. [Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Centre for Mathematical Sciences, Wilberforce Road, Cambridge CB3 0WA (United Kingdom)

2011-02-15T23:59:59.000Z

82

Comparison of Model-Produced and Observed Microwave Radiances and Estimation of Background Error Covariances for Hydrometeor Variables within Hurricanes  

Science Conference Proceedings (OSTI)

A radiative transfer model was updated to better simulate Special Sensor Microwave Imager (SSM/I)–observed brightness temperatures in areas of high ice concentration. The difference between the lowest observed and model-produced brightness ...

Clark Amerault; Xiaolei Zou

2006-03-01T23:59:59.000Z

83

Tests for Gaussianity of the MAXIMA-1 cosmic microwave backgroundmap  

SciTech Connect

Gaussianity of the cosmological perturbations is one of the key predictions of standard inflation, but it is violated by other models of structure formation such as cosmic defects. We present the first test of the Gaussianity of the cosmic microwave background (CMB) on subdegree angular scales, where deviations from Gaussianity are most likely to occur. We apply the methods of moments, cumulants, the Kolmogorov test, the chi (2) test, and Minkowski functionals in eigen, real, Wiener-filtered, and signal-whitened spaces, to the MAXIMA-1 CMB anisotropy data. We find that the data, which probe angular scales between 10 arcmin and 5 deg, are consistent with Gaussianity. These results show consistency with the standard inflation and place constraints on the existence of cosmic defects.

Wu, J.H.P.; Balbi, A.; Borrill, J.; Ferreira, P.G.; Hanany, S.; Jaffe, A.H.; Lee, A.T.; Rabii, B.; Richards, P.L.; Smoot, G.F.; Stompor,R.; Winant, C.D.

2001-04-14T23:59:59.000Z

84

The Universe Adventure - Origins of the CMB  

NLE Websites -- All DOE Office Websites (Extended Search)

Origins of the CMB Decoupling of Matter The first light radiated after decoupling is now known as the CMB. During the first 380,000 years after the Big Bang, the universe was so...

85

Second Season QUIET Observations: Measurements of the CMB Polarization Power Spectrum at 95 GHz  

Science Conference Proceedings (OSTI)

The Q/U Imaging ExperimenT (QUIET) has observed the cosmic microwave background (CMB) at 43 and 95GHz. The 43-GHz results have been published in QUIET Collaboration et al. (2011), and here we report the measurement of CMB polarization power spectra using the 95-GHz data. This data set comprises 5337 hours of observations recorded by an array of 84 polarized coherent receivers with a total array sensitivity of 87 {mu}K{radical}s. Four low-foreground fields were observed, covering a total of {approx} 1000 square degrees with an effective angular resolution of 12'.8, allowing for constraints on primordial gravitational waves and high-signal-to-noise measurements of the E-modes across three acoustic peaks. The data reduction was performed using two independent analysis pipelines, one based on a pseudo-C{ell} (PCL) cross-correlation approach, and the other on a maximum-likelihood (ML) approach. All data selection criteria and filters were modified until a predefined set of null tests had been satisfied before inspecting any non-null power spectrum. The results derived by the two pipelines are in good agreement. We characterize the EE, EB and BB power spectra between {ell} = 25 and 975 and find that the EE spectrum is consistent with {Lambda}CDM, while the BB power spectrum is consistent with zero. Based on these measurements, we constrain the tensor-to-scalar ratio to r = 1.1{sup +0.9}{sub -0.8} (r pipeline, and r = {sup +0.9}{sub -0.8} (r pipeline. In one of the fields, we find a correlation with the dust component of the Planck Sky Model, though the corresponding excess power is small compared to statistical errors. Finally, we derive limits on all known systematic errors, and demonstrate that these correspond to a tensor-to-scalar ratio smaller than r = 0.01, the lowest level yet reported in the literature.

Araujo, D.; /Columbia U., CBA; Bischoff, C.; /Chicago U., EFI /Harvard-Smithsonian Ctr. Astrophys.; Brizius, A.; /Chicago U., EFI /Bonn, Max Planck Inst., Radioastron.; Buder, I.; /Chicago U., EFI /Harvard-Smithsonian Ctr. Astrophys.; Chinone, Y.; /KEK, Tsukuba /Tohoku U.; Cleary, K.; /Caltech; Dumoulin, R.N.; /Columbia U., CBA; Kusaka, A.; /Chicago U., EFI /Princeton U.; Monsalve, R.; /Miami U.; ss, S.K.N\\ae; /Oslo U.; Newburgh, L.B.; /Columbia U., CBA /Princeton U. /Caltech

2012-07-01T23:59:59.000Z

86

Observational Constraints on Microwave Anisotropy from Point Sources  

E-Print Network (OSTI)

Applying basic physical principles to recent observational results, we derive upper and lower limits on microwave anisotropy from point sources over the range of frequencies 10-1000 GHz. We examine the level of noise in the observations as a possible indication of source confusion at subarcminute scales. We also derive an upper limit on microwave anisotropy caused by the sources responsible for the Far-Infrared Background radiation detected in FIRAS data. Our upper limit on point source confusion of DeltaT/T=10^{-5} for a 10' beam at 100 GHz would cause severe foreground contamination for CMB anisotropy observations, although the actual contamination level is probably much lower. This upper limit constrains the long-feared possibility of an undetected population of sources with emission peaking near 100 GHz. Source detections closer to 100 GHz are needed to improve our knowledge of galaxy evolution at high redshift and to predict the level of point source confusion.

Eric Gawiser; Andrew Jaffe; Joseph Silk

1998-11-10T23:59:59.000Z

87

CMB polarization: Scientific case and data analysis issues  

Science Conference Proceedings (OSTI)

We review the science case for studying CMB polarization. We then discuss the main issues related to the analysis of forth-coming polarized CMB data

A. Balbi; P. Cabella; G. de Gasperis; P. Natoli; N. Vittorio

2002-01-01T23:59:59.000Z

88

Joint cosmological parameters forecast from CFHTLS-cosmic shear and CMB data  

E-Print Network (OSTI)

We present a prospective analysis of a combined cosmic shear and cosmic microwave background data set, focusing on a Canada France Hawaii Telescope Legacy Survey (CFHTLS) type lensing survey and the current WMAP-1 year and CBI data. We investigate the parameter degeneracies and error estimates of a seven parameters model, for the lensing alone as well as for the combined experiments. The analysis is performed using a Monte Carlo Markov Chain calculation, allowing for a more realistic estimate of errors and degeneracies than a Fisher matrix approach. After a detailed discussion of the relevant statistical techniques, the set of the most relevant 2 and 3-dimensional lensing contours are given. It is shown that the combined cosmic shear and CMB is particularly efficient to break some parameter degeneracies. The principal components directions are computed and it is found that the most orthogonal contours between the two experiments are for the parameter pairs (Omega_m,sigma_8), (h,ns) and (ns,nrun), where ns and nrun are the slope of the primordial mass power spectrum and the running spectral index respectively. It is shown that an improvement of a factor 2 is expected on the running spectral index from the combined data sets. Forecasts for error improvements from a wide field space telescope lensing survey are also given.

I. Tereno; O. Doré; L. van Waerbeke; Y. Mellier

2004-04-15T23:59:59.000Z

89

Using BBN in cosmological parameter extraction from CMB: a forecast for Planck  

E-Print Network (OSTI)

Data from future high-precision Cosmic Microwave Background (CMB) measurements will be sensitive to the primordial Helium abundance $Y_p$. At the same time, this parameter can be predicted from Big Bang Nucleosynthesis (BBN) as a function of the baryon and radiation densities, as well as a neutrino chemical potential. We suggest to use this information to impose a self-consistent BBN prior on $Y_p$ and determine its impact on parameter inference from simulated Planck data. We find that this approach can significantly improve bounds on cosmological parameters compared to an analysis which treats $Y_p$ as a free parameter, if the neutrino chemical potential is taken to vanish. We demonstrate that fixing the Helium fraction to an arbitrary value can seriously bias parameter estimates. Under the assumption of degenerate BBN (i.e., letting the neutrino chemical potential $\\xi$ vary), the BBN prior's constraining power is somewhat weakened, but nevertheless allows us to constrain $\\xi$ with an accuracy that rivals bounds inferred from present data on light element abundances.

Jan Hamann; Julien Lesgourgues; Gianpiero Mangano

2007-12-18T23:59:59.000Z

90

The CMB in a Causal Set Universe  

E-Print Network (OSTI)

We discuss Cosmic Microwave Background constraints on the causal set theory of quantum gravity, which has made testable predictions about the nature of dark energy. We flesh out previously discussed heuristic constraints by showing how the power spectrum of causal set dark energy fluctuations can be found from the overlap volumes of past light cones of points in the universe. Using a modified Boltzmann code we put constraints on the single parameter of the theory that are somewhat stronger than previous ones. We conclude that causal set theory cannot explain late-time acceleration without radical alterations to General Relativity.

Joe Zuntz

2007-11-19T23:59:59.000Z

91

Cosmological implications of the MAXIMA-1 high-resolution cosmicmicrowave background anisotropy measurement  

SciTech Connect

We discuss the cosmological implications of the new constraints on the power spectrum of the cosmic microwave background (CMB) anisotropy derived from a new high-resolution analysis of the MAXIMA-1 measurement. The power spectrum indicates excess power at lsimilar to 860 over the average level of power at 411 less than or equal to l less than or equal to 785. This excess is statistically significant at the similar to 95 percent confidence level. Its position coincides with that of the third acoustic peak, as predicted by generic inflationary models selected to fit the first acoustic peak as observed in the data. The height of the excess power agrees with the predictions of a family of inflationary models with cosmological parameters that are fixed to fit the CMB data previously provided by BOOMERANG-LDB and MAXIMA-1 experiments. Our results therefore lend support for inflationary models and more generally for the dominance of adiabatic coherent perturbations in the structure formation of the universe. At the same time, they seem to disfavor a large variety of the nonstandard (but inflation-based) models that have been proposed to improve the quality of fits to the CMB data and the consistency with other cosmological observables. Within standard inflationary models, our results combined with the COBE/Differential Microwave Radiometer data give best-fit values and 95 percent confidence limits for the baryon density, Omega (b)h(2)similar or equal to 0.033 +/- 0.013, and the total density, Omega =0.9(-0.16)(+0.18). The primordial spectrum slope (n(s)) and the optical depth to the last scattering surface (tau (c)) are found to be degenerate and to obey the relation n(s) similar or equal to (0.99 +/- 0.14) + 0.46tau (c), for tau (c) less than or equal to 0.5 (all at 95 percent confidence levels).

Stompor, R.; Abroe, M.; Ade, P.; Balbi, A.; Barbosa, D.; Bock,J.; Borrill, J.; Boscaleri, A.; de Bernardis, P.; Ferreira, P.G.; Hanany,S.; Hristov, V.; Jaffe, A.H.; Lee, A.T.; Pascale, E.; Rabii, B.; Richards, P.L.; Smoot, G.F.; Winant, C.D.; Wu, J.H.P.

2001-05-03T23:59:59.000Z

92

Analytic calculations of the spectra of ultra high energy cosmic ray nuclei. II. The general case of background radiation  

E-Print Network (OSTI)

We discuss the problem of ultra high energy nuclei propagation in extragalactic background radiations. The present paper is the continuation of the accompanying paper I where we have presented three new analytic methods to calculate the fluxes and spectra of Ultra High Energy Cosmic Ray (UHECR) nuclei, both primary and secondary, and secondary protons. The computation scheme in this paper is based on the analytic solution of coupled kinetic equations, which takes into account the continuous energy losses due to the expansion of the universe and pair-production, together with photo-disintegration of the nuclei. This method includes in the most natural way the production of secondary nuclei in the process of photo-disintegration of the primary nuclei during their propagation through extragalactic background radiations. In paper I, in order to present the suggested analytical schemes of calculations, we have considered only the case of the Cosmic Microwave Background (CMB) radiation, in the present paper we gene...

Aloisio, R; Grigorieva, S

2013-01-01T23:59:59.000Z

93

Blind component separation in wavelet space: application to CMB analysis  

Science Conference Proceedings (OSTI)

It is a recurrent issue in astronomical data analysis that observations are incomplete maps with missing patches or intentionally masked parts. In addition, many astrophysical emissions are nonstationary processes over the sky. All these effects impair ... Keywords: blind source separation, cosmic microwave background, data analysis, missing data, wavelets

Y. Moudden; J.-F. Cardoso; J.-L. Starck; J. Delabrouille

2005-01-01T23:59:59.000Z

94

Window Function for Non-Circular Beam CMB Anisotropy Experiment  

E-Print Network (OSTI)

We develop computationally rapid methods to compute the window function for a cosmic microwave background anisotropy experiment with a non-circular beam which scans over large angles on the sky. To concretely illustrate these methods we compute the window function for the Python V experiment which scans over large angles on the sky with an elliptical Gaussian beam.

Tarun Souradeep; Bharat Ratra

2001-05-16T23:59:59.000Z

95

Neural networks and separation of background and foregrounds in astrophysical sky maps  

E-Print Network (OSTI)

The Independent Component Analysis (ICA) algorithm is implemented as a neural network for separating signals of different origin in astrophysical sky maps. Due to its self-organizing capability, it works without prior assumptions on the signals, neither on their frequency scaling, nor on the signal maps themselves; instead, it learns directly from the input data how to separate the physical components, making use of their statistical independence. To have a first insight into the capabilities of this approach, we apply the ICA algorithm on sky patches, taken from simulations and observations, at the microwave frequencies, that are going to be deeply explored in a few years on the whole sky, by the Microwave Anisotropy Probe (MAP) and by the Planck Surveyor Satellite. The maps are at the frequencies of the Low Frequency Instrument (LFI) aboard the Planck satellite (30, 44, 70 and 100 GHz), and contain simulated astrophysical radio sources, Cosmic Microwave Background (CMB) radiation, and Galactic diffuse emissions from thermal dust and synchrotron. We show that the ICA algorithm is able to recover each

C. Baccigalupi; L. Bedini; C. Burigana; G. De Zotti; A. Farusi; D. Maino; M. Maris; F. Perrotta; E. Salerno; L. Toffolatti; A. Tonazzini

2008-01-01T23:59:59.000Z

96

Scanning and Mapping Strategies for CMB Experiments  

E-Print Network (OSTI)

CMB anisotropy experiments seeking to make maps with more pixels than the 6144 pixels used by the COBE DMR need to address the practical issues of the computer time and storage required to make maps. A simple, repetitive scan pattern reduces these requirements but leaves the experiment vulnerable to systematic errors and striping in the maps. In this paper I give a time-ordered method for map-making with one-horned experiments that has reasonable memory and CPU needs but can handle complex COBE-like scans paths and 1/f noise.

Edward L. Wright

1996-11-29T23:59:59.000Z

97

Forecast Constraints on Inflation from Combined CMB and Gravitational Wave Direct Detection Experiments  

E-Print Network (OSTI)

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

2009-12-18T23:59:59.000Z

98

An "Ultrasonic Image" of the Embryonic Universe: CMB Polarization Tests of the Inflationary Paradigm  

E-Print Network (OSTI)

This chapter describes how the Cosmic Gravitational Wave Background induces a specific type of CMB polarization and describes the first experiment dedicated to testing this most-promising signature of inflation. This experiment, the Background Imaging of Cosmic Extragalactic Polarization (BICEP) project, has recently embarked on its third observing season. We show preliminary data from the BICEP's first season obtained with a novel polarization modulation mechanism called the "Faraday Rotation Modulator". Our discussion ends with a description of exciting new technology with the potential to probe inflation down to the GUT-scale.

Brian G. Keating

2008-06-11T23:59:59.000Z

99

MADCAP - The Microwave Anisotropy Dataset Computational Analysis Package  

E-Print Network (OSTI)

In the standard model of cosmology the universe starts with a hot Big Bang. As the universe expands it cools, and after 300,000 years it drops below the ionisation temperature of hydrogen. The previously free electrons become bound to protons, and with no electrons for the photons to scatter off they continue undeflected to us today. This image of the surface of last-scattering is what we call the Cosmic (because it fills the universe) Microwave (because of the frequency at which its black body spectrum peaks today) Background (because it originates behind all other light sources). Despite its stunning uniformity - isotropic to a few parts in a million - it is the tiny perturbations in the CMB that give us an unprecedented view of the early universe. First detected by the COBE satellite in 1991, these anisotropies are an imprint of the primordial density fluctuations needed to seed the development of gravitationally bound objects in the universe, and are potentially the most powerful discriminant between cosmological models. Realizing the extraordinary scientific potential of the CMB requires precise measurements of these tiny anisotropies over a significant fraction of the sky at very high resolution. The analysis of the resulting datasets is a serious computational challenge. Existing algorithms require terabytes of memory and hundreds of years of CPU time. We must therefore both maximize our resources by moving to supercomputers and minimize our requirements by algorithmic development. Here we will outline the nature of the challenge, present our current optimal algorithm, discuss its implementation - as the MADCAP software package - and its application to data from the North American test flight of the joint Italian-U.S. BOOMERanG experiment on the Cray T3E at NERSC...

Julian Borrill

1999-01-01T23:59:59.000Z

100

CMB in a box: causal structure and the Fourier-Bessel expansion  

E-Print Network (OSTI)

This paper makes two points. First, we show that the line-of-sight solution to cosmic microwave anisotropies in Fourier space, even though formally defined for arbitrarily large wavelengths, leads to position-space solutions which only depend on the sources of anisotropies inside the past light-cone of the observer. This happens order by order in a series expansion in powers of the visibility $\\gamma=e^{-\\mu}$, where $\\mu$ is the optical depth to Thompson scattering. We show that the CMB anisotropies are regulated by spacetime window functions which have support only inside the past light-cone of the point of observation. Second, we show that the Fourier-Bessel expansion of the physical fields (including the temperature and polarization momenta) is an alternative to the usual Fourier basis as a framework to compute the anisotropies. In that expansion, for each multipole $l$ there is a discrete tower of momenta $k_{i,l}$ (not a continuum) which can affect physical observables, with the smallest momenta being $k_{1,l} ~ l$. The Fourier-Bessel modes take into account precisely the information from the sources of anisotropies that propagates from the initial value surface to the point of observation - no more, no less. We also show that the physical observables (the temperature and polarization maps), and hence the angular power spectra, are unaffected by that choice of basis. This implies that the Fourier-Bessel expansion is the optimal scheme with which one can compute CMB anisotropies. (Abridged)

L. Raul Abramo; Paulo H. Reimberg; Henrique S. Xavier

2010-05-04T23:59:59.000Z

Note: This page contains sample records for the topic "microwave background cmb" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

CMB temperature anisotropy from broken spatial isotropy due to a homogeneous cosmological magnetic field  

Science Conference Proceedings (OSTI)

We derive the cosmic microwave background temperature anisotropy two-point correlation function (including off-diagonal correlations) from broken spatial isotropy due to an arbitrarily oriented homogeneous cosmological magnetic field.

Kahniashvili, Tina [Department of Physics, Kansas State University, 116 Cardwell Hall, Manhattan, Kansas 66506 (United States); Department of Physics, Laurentian University, Ramsey Lake Road, Sudbury, ON P3E 2C6 (Canada); National Abastumani Astrophysical Observatory, 2A Kazbegi Ave, Tbilisi, GE-0160 (Georgia); Lavrelashvili, George [Department of Theoretical Physics, A. Razmadze Mathematical Institute, 1 M. Aleksidze, Tbilisi, GE-0193 (Georgia); Ratra, Bharat [Department of Physics, Kansas State University, 116 Cardwell Hall, Manhattan, Kansas 66506 (United States)

2008-09-15T23:59:59.000Z

102

Differential Microwave Radiometer and the Cosmic Microwave Background...  

Office of Science (SC) Website

Contacts Technology Transfer DOE National Laboratories Contact Information Laboratory Policy and Evaluation U.S. Department of Energy SC-32Forrestal Building 1000 Independence...

103

Signature of cosmic string wakes in the CMB polarization  

Science Conference Proceedings (OSTI)

We calculate a signature of cosmic strings in the polarization of the cosmic microwave background. We find that ionization in the wakes behind moving strings gives rise to extra polarization in a set of rectangular patches in the sky whose length distribution is scale-invariant. The length of an individual patch is set by the comoving Hubble radius at the time the string is perturbing the cosmic microwave background. The polarization signal is largest for string wakes produced at the earliest post-recombination time, and for an alignment in which the photons cross the wake close to the time the wake is created. The maximal amplitude of the polarization relative to the temperature quadrupole is set by the overdensity of free electrons inside a wake which depends on the ionization fraction f inside the wake. For a cosmic string wake coming from an idealized string segment, the signal can be as high as 0.06 {mu}K in degree scale polarization for a string at high redshift (near recombination) and a string tension {mu} given by G{mu}=10{sup -7}.

Danos, Rebecca J.; Brandenberger, Robert H.; Holder, Gil [Department of Physics, McGill University, Montreal, QC, H3A 2T8 (Canada)

2010-07-15T23:59:59.000Z

104

Search for the Cosmic Neutrino Background and KATRIN  

E-Print Network (OSTI)

The Cosmic Microwave Background (CMB) has been detected in 1964 by Penzias and Wilson. It shows today a remarkable constant temperature of T ~ 2.7 K independent of the direction. Present density is about 370 photons per cubic-cm. The size of the hot spots, which deviates only in the fifth decimal of the temperature from the average value, tells us, that the universe is flat. About 300 000 years after the Big Bang at a temperature of T = 3000 K already in the matter dominated era the electrons combine with the protons and 4He and the photons move freely in the neutral universe. So the temperature and distribution of the photons give us information of the universe 300 000 years after the Big Bang. Information about earlier times can, in principle, be derived from the Cosmic Neutrino Background. The neutrinos decouple already 1 second after the Big Bang at a temperature of about 10^{10} K. Today their temperature is ~ 1.95 K and the average density is 56 electron-neutrinos per cubic-cm. Registration of these neutrinos is an extremely challenging experimental problem which can hardly be solved with the present technologies. On the other hand it represents a tempting opportunity to check one of the key element of the Big Bang cosmology and to probe the early stages of the universe evolution. The search for the cosmic relic neutrinos with the induced beta decay Electron-neutrino + 3H --> 3He + e- is the topic of this contribution. The signal would show up by a peak in the electron spectrum with an energy of the neutrino mass above the Q value. We discuss the prospects of this approach and argue that it is able to set limits on the relic neutrino density in our vicinity.

Amand Faessler; Rastislav Hodak; Sergey Kovalenko; Fedor Simkovic

2013-04-20T23:59:59.000Z

105

Microwave detector  

DOE Patents (OSTI)

A microwave detector is provided for measuring the envelope shape of a microwave pulse comprised of high-frequency oscillations. A biased ferrite produces a magnetization field flux that links a B-dot loop. The magnetic field of the microwave pulse participates in the formation of the magnetization field flux. High-frequency insensitive means are provided for measuring electric voltage or current induced in the B-dot loop. The recorded output of the detector is proportional to the time derivative of the square of the envelope shape of the microwave pulse.

Meldner, H.W.; Cusson, R.Y.; Johnson, R.M.

1985-02-08T23:59:59.000Z

106

Microwave detector  

SciTech Connect

A microwave detector (10) is provided for measuring the envelope shape of a microwave pulse comprised of high-frequency oscillations. A biased ferrite (26, 28) produces a magnetization field flux that links a B-dot loop (16, 20). The magnetic field of the microwave pulse participates in the formation of the magnetization field flux. High-frequency insensitive means (18, 22) are provided for measuring electric voltage or current induced in the B-dot loop. The recorded output of the detector is proportional to the time derivative of the square of the envelope shape of the microwave pulse.

Meldner, Heiner W. (Moss Beach, CA); Cusson, Ronald Y. (Chapel Hill, NC); Johnson, Ray M. (San Ramon, CA)

1986-01-01T23:59:59.000Z

107

A Hydrodynamical Approach to CMB mu-distortions  

E-Print Network (OSTI)

Spectral distortion of the cosmic microwave background provides a unique opportunity to probe primordial perturbations on very small scales by performing large-scale measurements. We discuss in a systematic and pedagogic way all the relevant physical phenomena involved in the production and evolution of the mu-type spectral distortion. Our main results agree with previous estimates (in particular we show that a recently found factor of 3/4 arises from relativistic corrections to the wave energy). We also discuss several subleading corrections such as adiabatic cooling and the effects of bulk viscosity, baryon loading and photon heat conduction. Finally we calculate the transfer function for mu-distortions between the end of the mu-era and now.

Enrico Pajer; Matias Zaldarriaga

2012-06-20T23:59:59.000Z

108

MASKING VERSUS REMOVING POINT SOURCES IN CMB DATA: THE SOURCE-CORRECTED WMAP POWER SPECTRUM FROM NEW EXTENDED CATALOG  

Science Conference Proceedings (OSTI)

In Scodeller et al., a new and extended point source catalog obtained from the Wilkinson Microwave Anisotropy Probe (WMAP) seven-year data was presented. It includes most of the sources included in the standard WMAP seven-year point source catalogs as well as a large number of new detections. Here, we study the effects on the estimated CMB power spectrum when taking the newly detected point sources into consideration. We create point source masks for all the 2102 sources that we detected as well as a smaller one for the 665 sources detected in the Q, V, and W bands. We also create WMAP7 maps with point sources subtracted in order to compare with the spectrum obtained with source masks. The extended point source masks and point source cleaned WMAP7 maps are made publicly available. Using the proper residual correction, we find that the CMB power spectrum obtained from the point source cleaned map without any source mask is fully consistent with the spectrum obtained from the masked map. We further find that the spectrum obtained masking all 2102 sources is consistent with the results obtained using the standard WMAP seven-year point source mask (KQ85y7). We also verify that the removal of point sources does not introduce any skewness.

Scodeller, Sandro; Hansen, Frode K., E-mail: sandro.scodeller@astro.uio.no, E-mail: frodekh@astro.uio.no [Institute of Theoretical Astrophysics, University of Oslo, P.O. Box 1029 Blindern, NO-0315 Oslo (Norway)

2012-12-20T23:59:59.000Z

109

Bolivia Background  

U.S. Energy Information Administration (EIA)

‹ Countries Bolivia Last Updated: August 23, 2012 Background The energy sector is of political and economic significance to Bolivia, which is a ...

110

CMB Anisotropy Induced by a Moving Straight Cosmic String  

E-Print Network (OSTI)

We showed that the part of strings could be detected by optical method is only 20% from the total available amount of such objects, therefore the gravitational lensing method has to be "completed" by CMB one. We found the general structure of the CMB anisotropy generated by a cosmic string for simple model of straight string moving with constant velocity. For strings with deficit angle 1-2 arcsec the amplitude of generated anisotropy has to be 15-30 muK (the corresponding string linear density is (G mu) ~ 10^{-7} and energy is GUT one, 10^{15} GeV). To use both radio and optical methods the deficit angle has to be from 0.1 arcsec to 5-6 arcsec. If cosmic string can be detected by optical method, the length of corresponding brightness spot of anisotropy has to be no less than 100 degrees.

O. S. Sazhina; M. V. Sazhin; V. N. Sementsov; M. Capaccioli; G. Longo; G. Riccio; G. D'Angelo

2008-09-05T23:59:59.000Z

111

CMB in a box: causal structure and the Fourier-Bessel expansion  

E-Print Network (OSTI)

This paper makes two points. First, we show that the line-of-sight solution to cosmic microwave anisotropies in Fourier space, even though formally defined for arbitrarily large wavelengths, leads to position-space solutions which only depend on the sources of anisotropies inside the past light-cone of the observer. This happens order by order in a series expansion in powers of the visibility $\\gamma=e^{-\\mu}$, where $\\mu$ is the optical depth to Thompson scattering. We show that the CMB anisotropies are regulated by spacetime window functions which have support only inside the past light-cone of the point of observation. Second, we show that the Fourier-Bessel expansion of the physical fields (including the temperature and polarization momenta) is an alternative to the usual Fourier basis as a framework to compute the anisotropies. In that expansion, for each multipole $l$ there is a discrete tower of momenta $k_{i,l}$ (not a continuum) which can affect physical observables, with the smallest momenta being $...

Abramo, L Raul; Xavier, Henrique S

2010-01-01T23:59:59.000Z

112

Legal Background  

Office of Legacy Management (LM)

Legal Background Legal Background Book 1 . . Project Rulison :.Contract: . . AEC, Austral Oil Company, and CER Geonuclear Corporation, . . . . , . . . . , . . February 1969 DISCLAIMER Portions of this document may be illegible in electronic image products. Images are produced from the best available original document. PROJECT RULISON CONTRACT NO. UNITED STATES OF AMERICA REPRESENTED BY THE ATOMIC ENERGY COMMISSION and THE DEPARTMENT. OF THE INTERIOR and AUSTRAL OIL COMPANY INCORPORATED and CER GEONUCLEAR CORPORATION Prepared by OFFICE OF THE CHIEF COUNSEL NEVADA OPERATIONS OFFICE FEBRUARY 1969 This page intentionally left blank UNITED STATES ATOMIC ENERGY COMMISSION . NEVADA OPERATIONS OFFICE TABLE OF CONTENTS VII VIII XV XVI XVII SUBJECT - PAGE Definitions 2 Description of Project ~ulisdn 3

113

Sensitive Detection of CMB B-Mode Polarization : : Instrumentation and Systematics  

E-Print Network (OSTI)

CMB B-Mode Polarization: Instrumentation and Systematics AFar-Infrared Detectors and Instrumentation for Astronomy VI,Far-Infrared Detectors and Instrumentation for Astronomy VI,

Moyerman, Stephanie

114

Microwave furnace having microwave compatible dilatometer  

DOE Patents (OSTI)

An apparatus for measuring and monitoring a change in the dimension of a sample being heated by microwave energy is described. The apparatus comprises a microwave heating device for heating a sample by microwave energy, a microwave compatible dilatometer for measuring and monitoring a change in the dimension of the sample being heated by microwave energy without leaking microwaves out of the microwave heating device, and a temperature determination device for measuring and monitoring the temperature of the sample being heated by microwave energy. 2 figs.

Kimrey, H.D. Jr.; Janney, M.A.; Ferber, M.K.

1992-03-24T23:59:59.000Z

115

Forecasting Cosmic Doomsday from CMB/LSS Cross-Correlations  

E-Print Network (OSTI)

A broad class of dark energy models, which have been proposed in attempts at solving the cosmological constant problems, predict a late time variation of the equation of state with redshift. The variation occurs as a scalar field picks up speed on its way to negative values of the potential. The negative potential energy eventually turns the expansion into contraction and the local universe undergoes a big crunch. In this paper we show that cross-correlations of the CMB anisotropy and matter distribution, in combination with other cosmological data, can be used to forecast the imminence of such cosmic doomsday.

Jaume Garriga; Levon Pogosian; Tanmay Vachaspati

2003-11-17T23:59:59.000Z

116

CMVRTC: Background  

NLE Websites -- All DOE Office Websites (Extended Search)

newsletters newsletters contacts tools latest news 12.05.2013 Next Quarterly meeting scheduled for February 19, 2014 (10 a.m. - 12 p.m. ET). read more ... More information CMVRTC Showcase Events CMVRTC Poster Sessions Related Projects Heavy Truck Duty Cycle Medium Truck Duty Cycle Fuel Tax Evasion Other technical director For more information, please contact Gary Capps, Technical Director, at cappsgj@ornl.gov or (865) 946-1285. Background Introduction Vision cmvrtc poster Benefits Technology Transfer Introduction The Federal Motor Carrier Safety Administration (FMCSA) launched the Commercial Motor Vehicle Roadside Technology Corridor (CMVRTC) on August 7, 2007, in partnership with the Tennessee Departments of Safety and Transportation, the Oak Ridge National Laboratory (ORNL), and the

117

CMB Maximum Temperature Asymmetry Axis: Alignment with Other Cosmic Asymmetries  

E-Print Network (OSTI)

We use a global pixel based estimator to identify the axis of the residual Maximum Temperature Asymmetry (MTA) (after the dipole subtraction) of the WMAP 7 year Internal Linear Combination (ILC) CMB temperature sky map. The estimator is based on considering the temperature differences between opposite pixels in the sky at various angular resolutions (4 degrees-15 degrees and selecting the axis that maximizes this difference. We consider three large scale Healpix resolutions (N_{side}=16 (3.7 degrees), N_{side}=8 (7.3 degrees) and N_{side}=4 (14.7 degrees)). We compare the direction and magnitude of this asymmetry with three other cosmic asymmetry axes (\\alpha dipole, Dark Energy Dipole and Dark Flow) and find that the four asymmetry axes are abnormally close to each other. We compare the observed MTA axis with the corresponding MTA axes of 10^4 Gaussian isotropic simulated ILC maps (based on LCDM). The fraction of simulated ILC maps that reproduces the observed magnitude of the MTA asymmetry and alignment with the observed \\alpha dipole is in the range of 0.1%-0.5%$ (depending on the resolution chosen for the CMB map). The corresponding magnitude+alignment probabilities with the other two asymmetry axes (Dark Energy Dipole and Dark Flow) are at the level of about 1%. We propose Extended Topological Quintessence as a physical model qualitatively consistent with this coincidence of directions.

Antonio Mariano; Leandros Perivolaropoulos

2012-11-26T23:59:59.000Z

118

CMB quadrupole suppression. II. The early fast roll stage  

Science Conference Proceedings (OSTI)

Within the effective field theory of inflation, an initialization of the classical dynamics of the inflaton with approximate equipartition between the kinetic and potential energy of the inflaton leads to a brief fast roll stage that precedes the slow roll regime. The fast roll stage leads to an attractive potential in the wave equations for the mode functions of curvature and tensor perturbations. The evolution of the inflationary perturbations is equivalent to the scattering by this potential and a useful dictionary between the scattering data and observables is established. Implementing methods from scattering theory we prove that this attractive potential leads to a suppression of the quadrupole moment for CMB and B-mode angular power spectra. The scale of the potential is determined by the Hubble parameter during slow roll. Within the effective field theory of inflation at the grand unification (GUT) energy scale we find that if inflation lasts a total number of e-folds N{sub tot}{approx}59, there is a 10%-20% suppression of the CMB quadrupole and about 2%-4% suppression of the tensor quadrupole. The suppression of higher multipoles is smaller, falling off as 1/l{sup 2}. The suppression is much smaller for N{sub tot}>59, therefore if the observable suppression originates in the fast roll stage, there is the upper bound N{sub tot}{approx}59.

Boyanovsky, D.; Vega, H. J. de [Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, Pennsylvania 15260 (United States); Observatoire de Paris, LERMA, Laboratoire Associe au CNRS UMR 8112, 61, Avenue de l'Observatoire, 75014 Paris (France); LPTHE, Universite Pierre et Marie Curie (Paris VI) et Denis Diderot (Paris VII), Laboratoire Associe au CNRS UMR 7589, Tour 24, 5eme. etage, 4, Place Jussieu, 75252 Paris, Cedex 05 (France); Sanchez, N. G. [Observatoire de Paris, LERMA, Laboratoire Associe au CNRS UMR 8112, 61, Avenue de l'Observatoire, 75014 Paris (France)

2006-12-15T23:59:59.000Z

119

--No Title--  

NLE Websites -- All DOE Office Websites (Extended Search)

the standard cosmological model: neutrinos and non-Gaussianity Tristan L. Smith (UC Berkeley) Abstract: The cosmic microwave background (CMB) has provided us the laboratory in...

120

From Cavendish to PLANCK: Constraining Newton's gravitational constant with CMB temperature and polarization anisotropy  

SciTech Connect

We present new constraints on cosmic variations of Newton's gravitational constant by making use of the latest CMB data from WMAP, BOOMERANG, CBI and ACBAR experiments and independent constraints coming from big bang nucleosynthesis. We found that current CMB data provide constraints at the {approx}10% level, that can be improved to {approx}3% by including big bang nucleosynthesis data. We show that future data expected from the Planck satellite could constrain G at the {approx}1.5% level while an ultimate, cosmic variance limited, CMB experiment could reach a precision of about 0.4%, competitive with current laboratory measurements.

Galli, Silvia; Melchiorri, Alessandro; Smoot, George F.; Zahn, Oliver [Physics Department, Universita di Roma 'La Sapienza', Ple Aldo Moro 2, 00185, Rome, Italy, and Laboratoire Astroparticule et Cosmologie (APC), Universite' Paris Diderot - 75205 PARIS cedex 13 (Italy); Physics Department and INFN, Universita di Roma 'La Sapienza', Ple Aldo Moro 2, 00185, Rome (Italy); Lawrence Berkeley National Laboratory and Berkeley Center for Cosmological Physics Physics Department, University of California, Berkeley California 94720 (United States)

2009-07-15T23:59:59.000Z

Note: This page contains sample records for the topic "microwave background cmb" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

From Microwave Anisotropies to Cosmology  

E-Print Network (OSTI)

Fluctuations in the temperature of the cosmic microwave background have now been detected over a wide range of angular scales, and a consistent picture seems to be emerging. This article describes some of the implications for cosmology. Analysis of all the published detections suggests the existence of a peak on degree scales of height 2.4 to 10 (90%CL) relative to the amplitude of the power spectrum at large angular scales. This result confirms an early prediction, implies that the universe did in fact recombine, and limits theories of structure formation. Illustrative examples are provided of how the comparison of microwave background and large-scale structure data will be a potentially powerful means of answering fundamental questions about the universe.

Douglas Scott; Joe Silk; Martin White

1995-05-04T23:59:59.000Z

122

Oscillations in the CMB from Axion Monodromy Inflation  

Science Conference Proceedings (OSTI)

We study the CMB observables in axion monodromy inflation. These well-motivated scenarios for inflation in string theory have monomial potentials over super-Planckian field ranges, with superimposed sinusoidal modulations from instanton effects. Such periodic modulations of the potential can drive resonant enhancements of the correlation functions of cosmological perturbations, with characteristic modulations of the amplitude as a function of wavenumber. We give an analytical result for the scalar power spectrum in this class of models, and we determine the limits that present data places on the amplitude and frequency of modulations. Then, incorporating an improved understanding of the realization of axion monodromy inflation in string theory, we perform a careful study of microphysical constraints in this scenario. We find that detectable modulations of the scalar power spectrum are commonplace in well-controlled examples, while resonant contributions to the bispectrum are undetectable in some classes of examples and detectable in others. We conclude that resonant contributions to the spectrum and bispectrum are a characteristic signature of axion monodromy inflation that, in favorable cases, could be detected in near-future experiments.

Flauger, Raphael; /Texas U.; McAllister, Liam; Pajer, Enrico; /Cornell U., Phys. Dept.; Westphal, Alexander; /SLAC /Stanford U., Phys. Dept.; Xu, Gang; /Cornell U., Phys. Dept.

2011-12-01T23:59:59.000Z

123

Boiling Water in Microwave  

NLE Websites -- All DOE Office Websites (Extended Search)

Boiling Water in Microwave A 26-year old man decided to have a cup of coffee. He took a cup of water and put it in the microwave to heat it up (something that he had done numerous...

124

Microwave Radiometer (MWR) Handbook  

SciTech Connect

The Microwave Radiometer (MWR) provides time-series measurements of column-integrated amounts of water vapor and liquid water. The instrument itself is essentially a sensitive microwave receiver. That is, it is tuned to measure the microwave emissions of the vapor and liquid water molecules in the atmosphere at specific frequencies.

Morris, VR

2006-08-01T23:59:59.000Z

125

arXiv:astro-ph/0407158v17Jul2004 Dark Energy Probes in Light of the CMB  

E-Print Network (OSTI)

arXiv:astro-ph/0407158v17Jul2004 Dark Energy Probes in Light of the CMB Wayne Hu Kavli Institute regime and provided two self-calibrated absolute standards for dark energy studies: the sound horizon redshift range or depth. The single most important complement to the CMB for measuring the dark energy

Hu, Wayne

126

THE TIME EVOLUTION OF THE COSMIC MICROWAVE BACKGROUND PHOTOSPHERE  

E-Print Network (OSTI)

of binucleated cells with micronuclei is reported for each stripe into which the samples have been sliced into respectively sliced into 3 mm, 2 mm, 1 mm and 0.2 mm wide stripes before being individually disaggregated in each individual stripe which the tissues were sliced. The results are reported as a function

127

Microwave hemorrhagic stroke detector  

DOE Patents (OSTI)

The microwave hemorrhagic stroke detector includes a low power pulsed microwave transmitter with a broad-band antenna for producing a directional beam of microwaves, an index of refraction matching cap placed over the patients head, and an array of broad-band microwave receivers with collection antennae. The system of microwave transmitter and receivers are scanned around, and can also be positioned up and down the axis of the patients head. The microwave hemorrhagic stroke detector is a completely non-invasive device designed to detect and localize blood pooling and clots or to measure blood flow within the head or body. The device is based on low power pulsed microwave technology combined with specialized antennas and tomographic methods. The system can be used for rapid, non-invasive detection of blood pooling such as occurs with hemorrhagic stoke in human or animal patients as well as for the detection of hemorrhage within a patient's body.

Haddad, Waleed S. (Dublin, CA); Trebes, James E. (Livermore, CA)

2007-06-05T23:59:59.000Z

128

CMB bounds on dark matter annihilation: nucleon energy-losses after recombination  

E-Print Network (OSTI)

We consider the propagation and energy losses of protons and anti-protons produced by dark matter annihilation at redshifts 100energy injected into e^\\pm and \\gamma's, but their interactions are normally neglected when deriving CMB bounds from altered recombination histories. Here, we follow numerically the energy-loss history of typical protons/antiprotons in the cosmological medium. We show that about half of their energy is channeled into photons and e^\\pm, and we present a simple prescription to estimate the corresponding strengthening of the CMB bounds on the dark matter annihilation cross section.

Weniger, Christoph; Iocco, Fabio; Bertone, Gianfranco

2013-01-01T23:59:59.000Z

129

Full-sky correlation functions for CMB experiments with asymmetric window functions  

E-Print Network (OSTI)

We discuss full-sky convolution of the instrumental beam with the CMB sky signal in CMB single-dish and interferometry experiments, using the method (Challinor et al. 2000) that the measured temperature and polarization anisotropies are defined globally on the group manifold of the three-dimensional rotation by means of Wigner D-functions. We re-derive the anisotropy and polarization correlation functions incorporated with asymmetric window functions, which are then explicitly calculated for a single-dish elliptical Gaussian beam and an interferometric Gaussian beam.

Kin-Wang Ng

2004-09-01T23:59:59.000Z

130

Dark Matter & Dark Energy from a single scalar field: CMB spectrum and matter transfer function  

E-Print Network (OSTI)

The dual axion model (DAM), yielding bot DM and DE form a PQ-like scalar field solving the strong CP problem, is known to allow a fair fit of CMB data. Recently, however, it was shown that its transfer function exhibits significant anomalies, causing difficulties to fit deep galaxy sample data. Here we show how DAM can be modified to agree with the latter data set. The modification follows the pattern suggested to reconcile any PQ-like approach with gravity. Modified DAM allows precise predictions which can be testable against future CMB and/or deep sample data.

Mainini Roberto; Silvio Bonometto

2007-09-03T23:59:59.000Z

131

Microwave Processing of Materials  

Science Conference Proceedings (OSTI)

Furthermore, lower energy consumption is another aspect that the world should consider to cope with this matter. Microwave processing of materials is a clean, ...

132

Cosmological constraints from the CMB and Ly-alpha forest revisited  

E-Print Network (OSTI)

The WMAP team has recently highlighted the usefulness of combining the Ly-alpha forest constraints with those from the cosmic microwave background. This combination is particularly powerful as a probe of the primordial shape of the power spectrum. Converting between the Ly-alpha forest observations and the linear mass power spectrum requires a careful treatment of nuisance parameters and modeling with cosmological simulations. We point out several errors and inconsistencies in the previous treatments that propagate into the estimations and associated errors of cosmological parameters, including those reported by the WMAP team. The two most important are the insufficient range of cosmological parameters explored in simulations used to date and an incorrect treatment of the mean transmitted flux constraints. We employ a likelihood calculator for the current data set based on an extensive 6-dimensional grid of simulations. We show that the current uncertainties in the mean transmission and the flux power spectru...

Seljak, U; Makarov, A; Seljak, Uros; Donald, Patrick Mc; Makarov, Alexey

2003-01-01T23:59:59.000Z

133

Real space estimator for the weak lensing convergence from the CMB  

E-Print Network (OSTI)

We propose an estimator defined in real space for the reconstruction of the weak lensing potential due to the intervening large scale structure from high resolution maps of the cosmic microwave background. This estimator was motivated as an alternative to the quadratic estimator in harmonic space to surpass the difficulties of the analysis of maps containing galactic cuts and point source excisions. Using maps synthesised by pixel remapping, we implement the estimator for two experiments, namely one in the absence and one in the presence of detector noise, and compare the reconstruction of the convergence field with that obtained with the quadratic estimator defined in harmonic space. We find good agreement between the input and the reconstructed power spectra using the proposed real space estimator. We discuss interesting features of the real space estimator and future extensions of this work.

Carvalho, C S

2010-01-01T23:59:59.000Z

134

Muon Collider Backgrounds  

NLE Websites -- All DOE Office Websites (Extended Search)

then, further improvements to the final focus have reduced the backgrounds by about an order of magnitude. Although challenging, in many ways the predicted background levels are...

135

DRAFT Microwave Radiometer Profiler Handbook  

NLE Websites -- All DOE Office Websites (Extended Search)

Microwave Radiometer Profiler Handbook Evaluation of a New Multi-Frequency Microwave Radiometer for Measuring the Vertical Distribution of Temperature, Water Vapor, and Cloud...

136

Microwave remote sensing of ionized air.  

SciTech Connect

We present observations of microwave scattering from ambient room air ionized with a negative ion generator. The frequency dependence of the radar cross section of ionized air was measured from 26.5 to 40 GHz (Ka-band) in a bistatic mode with an Agilent PNA-X series (model N5245A) vector network analyzer. A detailed calibration scheme is provided to minimize the effect of the stray background field and system frequency response on the target reflection. The feasibility of detecting the microwave reflection from ionized air portends many potential applications such as remote sensing of atmospheric ionization and remote detection of radioactive ionization of air.

Liao, S.; Gopalsami, N.; Heifetz, A.; Elmer, T.; Fiflis, P.; Koehl, E. R.; Chien, H. T.; Raptis, A. C. (Nuclear Engineering Division)

2011-07-01T23:59:59.000Z

137

Angular Power Spectrum of the Microwave Background Anisotropy seen by the COBE Differential Microwave Radiometer  

E-Print Network (OSTI)

The angular power spectrum estimator developed by Peebles (1973) and Hauser & Peebles (1973) has been modified and applied to the 2 year maps produced by the COBE DMR. The power spectrum of the real sky has been compared to the power spectra of a large number of simulated random skies produced with noise equal to the observed noise and primordial density fluctuation power spectra of power law form, with $P(k) \\propto k^n$. Within the limited range of spatial scales covered by the COBE DMR, corresponding to spherical harmonic indices $3 \\leq \\ell \\lsim 30$, the best fitting value of the spectral index is $n = 1.25^{+0.4}_{-0.45}$ with the Harrison-Zeldovich value $n = 1$ approximately 0.5$\\sigma$ below the best fit. For $3 \\leq \\ell \\lsim 19$, the best fit is $n = 1.46^{+0.39}_{-0.44}$. Comparing the COBE DMR $\\Delta T/T$ at small $\\ell$ to the $\\Delta T/T$ at $\\ell \\approx 50$ from degree scale anisotropy experiments gives a smaller range of acceptable spectral indices which includes $n = 1$.

E. L. Wright; G. F. Smoot; C. L. Bennett; P. M. Lubin

1994-01-11T23:59:59.000Z

138

Angular Power Spectrum of the Microwave Background Anisotropy seen by the COBE Differential Microwave Radiometer  

E-Print Network (OSTI)

The angular power spectrum estimator developed by Peebles (1973) and Hauser & Peebles (1973) has been modified and applied to the 4 year maps produced by the COBE DMR. The power spectrum of the observed sky has been compared to the power spectra of a large number of simulated random skies produced with noise equal to the observed noise and primordial density fluctuation power spectra of power law form, with $P(k) \\propto k^n$. The best fitting value of the spectral index in the range of spatial scales corresponding to spherical harmonic indices $3 \\leq \\ell \\lesssim 30$ is an apparent spectral index $n_{app}$ = 1.13 (+0.3) (-0.4) which is consistent with the Harrison-Zel'dovich primordial spectral index $n_{pri} = 1$ The best fitting amplitude for $n_{app} = 1$ is $\\langle Q_{RMS}^2\\rangle^{0.5}$ = 18 uK.

E. L. Wright; C. L. Bennett; K. Gorski; G. Hinshaw; G. F. Smoot

1996-01-12T23:59:59.000Z

139

Discovery potential of xenon-based neutrinoless double beta decay experiments in light of small angular scale CMB observations  

E-Print Network (OSTI)

The South Pole Telescope (SPT) has probed an expanded angular range of the CMB temperature power spectrum. Their recent analysis of the latest cosmological data prefers nonzero neutrino masses, mnu = 0.32+-0.11 eV. This result, if confirmed by the upcoming Planck data, has deep implications on the discovery of the nature of neutrinos. In particular, the values of the effective neutrino mass involved in neutrinoless double beta decay (bb0nu) are severely constrained for both the direct and inverse hierarchy, making a discovery much more likely. In this paper, we focus in xenon-based bb0nu experiments, on the double grounds of their good performance and the suitability of the technology to large-mass scaling. We show that the current generation, with effective masses in the range of 100 kg and conceivable exposures in the range of 500 kg year, could already have a sizable opportunity to observe bb0nu events, and their combined discovery potential is quite large. The next generation, with an exposure in the range of 10 ton year, would have a much more enhanced sensitivity, in particular due to the very low specific background that all the xenon technologies (liquid xenon, high-pressure xenon and xenon dissolved in liquid scintillator) can achieve. In addition, a high-pressure xenon gas TPC also features superb energy resolution. We show that such detector can fully explore the range of allowed effective Majorana masses, thus making a discovery very likely.

J. J. Gomez-Cadenas; J. Martin-Albo; J. Muñoz Vidal; C. Peña-Garay

2013-01-14T23:59:59.000Z

140

 

NLE Websites -- All DOE Office Websites (Extended Search)

microwave sky beyond CMB using cross correlations microwave sky beyond CMB using cross correlations Amir Hajian (CITA) Abstract: Past decade has been a golden era for precision cosmology. Cosmological surveys combined with Cosmic Microwave Background (CMB) provided us with valuable tools for studying the physics of the universe. Using a series of high-resolution and high-sensitivity CMB experiments, we have learned a great deal about the material content, shape and structure of the universe. These achievements have come about with the help of precise characterization of the statistical properties of the CMB fluctuations. In this talk, I will discuss the new astrophysical playground the current generation of the CMB experiments has opened up for us. I will describe how interesting information, beyond the traditional CMB power spectrum

Note: This page contains sample records for the topic "microwave background cmb" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Microwaves and Bacteria  

NLE Websites -- All DOE Office Websites (Extended Search)

Microwaves and Bacteria Microwaves and Bacteria Name: mike Location: N/A Country: N/A Date: N/A Question: Do the microwaves in a microwave kill bacteria or is it the heat that kills the bacteria? I am wondering this because i have a science fair project and i am searching for a project dealing with bacteria. Replies: As far as I'm aware it is the heat that kill bacteria in a microwave, and they need quite some time to be dead. The spores that some kind of bacteria make to survive harsh conditions do not contain much water and they might survive microwaves. I'm not sure what bacteria do that can survive high dosis of radiation, like Deinococcus radiodurans. They can do this by a very efficient repair system for their DNA. My guess is that they would also be killed by the heat generated in a microwave but I haven't found any data on this.

142

Microwave coupler and method  

DOE Patents (OSTI)

The present invention is directed to a microwave coupler for enhancing the heating or metallurgical treatment of materials within a cold-wall, rapidly heated cavity as provided by a microwave furnace. The coupling material of the present invention is an alpha-rhombohedral-boron-derivative-structure material such as boron carbide or boron silicide which can be appropriately positioned as a susceptor within the furnace to heat other material or be in powder particulate form so that composites and structures of boron carbide such as cutting tools, grinding wheels and the like can be rapidly and efficiently formed within microwave furnaces.

Holcombe, C.E.

1984-11-29T23:59:59.000Z

143

CMB and Matter Power Spectra of Early f(R) Cosmology in Palatini Formalism  

E-Print Network (OSTI)

We calculate in this article the CMB and matter power spectra of a class of early $f(R)$ cosmologies, which takes the form of $f(R) = R + \\lambda_1 H_0^2\\text{exp}[R/(\\lambda_2 H_0^2)]$. Unlike the late-time $f(R)$ cosmologies such as $f(R) = R + \\alpha(-R)^\\beta$ ($\\betaR)$ Cosmology}), and this important feature leads to rather different ISW effect and CMB spectrum. The matter power spectrum of this model is, at the same time, again very sensitive to the chosen parameters, and LSS observations such as SDSS should constrain the parameter space stringently. We expect that our results are applicable at least qualitatively to other models that produce $f(R)$ modification to GR at earlier times (\\emph{e.g.}, redshifts $\\mathcal{O}(10) \\lesssim z \\lesssim \\mathcal{O}(1)$) than when dark energy begins to dominate -- such models are strongly disfavored by data on CMB and matter power spectra.

Baojiu Li; Ming-Chung Chu

2006-10-16T23:59:59.000Z

144

Microwave fluid flow meter  

DOE Patents (OSTI)

A microwave fluid flow meter is described utilizing two spaced microwave sensors positioned along a fluid flow path. Each sensor includes a microwave cavity having a frequency of resonance dependent upon the static pressure of the fluid at the sensor locations. The resonant response of each cavity with respect to a variation in pressure of the monitored fluid is represented by a corresponding electrical output which can be calibrated into a direct pressure reading. The pressure drop between sensor locations is then correlated as a measure of fluid velocity. In the preferred embodiment the individual sensor cavities are strategically positioned outside the path of fluid flow and are designed to resonate in two distinct frequency modes yielding a measure of temperature as well as pressure. The temperature response can then be used in correcting for pressure responses of the microwave cavity encountered due to temperature fluctuations.

Billeter, Thomas R. (Richland, WA); Philipp, Lee D. (Richland, WA); Schemmel, Richard R. (Lynchburg, VA)

1976-01-01T23:59:59.000Z

145

Emitron: microwave diode  

DOE Patents (OSTI)

The invention comprises a new class of device, driven by electron or other charged particle flow, for producing coherent microwaves by utilizing the interaction of electromagnetic waves with electron flow in diodes not requiring an external magnetic field. Anode and cathode surfaces are electrically charged with respect to one another by electron flow, for example caused by a Marx bank voltage source or by other charged particle flow, for example by a high energy charged particle beam. This produces an electric field which stimulates an emitted electron beam to flow in the anode-cathode region. The emitted electrons are accelerated by the electric field and coherent microwaves are produced by the three dimensional spatial and temporal interaction of the accelerated electrons with geometrically allowed microwave modes which results in the bunching of the electrons and the pumping of at least one dominant microwave mode.

Craig, G.D.; Pettibone, J.S.; Drobot, A.T.

1982-05-06T23:59:59.000Z

146

High power microwave generator  

DOE Patents (OSTI)

A microwave generator efficiently converts the energy of an intense relativistic electron beam (REB) into a high-power microwave emission using the Smith-Purcell effect which is related to Cerenkov radiation. Feedback for efficient beam bunching and high gain is obtained by placing a cylindrical Smith-Purcell transmission grating on the axis of a toroidal resonator. High efficiency results from the use of a thin cold annular highly-magnetized REB that is closely coupled to the resonant structure.

Ekdahl, C.A.

1983-12-29T23:59:59.000Z

147

High power microwave generator  

DOE Patents (OSTI)

A microwave generator efficiently converts the energy of an intense relativistic electron beam (REB) into a high-power microwave emission using the Smith-Purcell effect which is related to Cerenkov radiation. Feedback for efficient beam bunching and high gain is obtained by placing a cylindrical Smith-Purcell transmission grating on the axis of a toroidal resonator. High efficiency results from the use of a thin cold annular highly-magnetized REB that is closely coupled to the resonant structure.

Ekdahl, Carl A. (Albuquerque, NM)

1986-01-01T23:59:59.000Z

148

Development of Generic Background  

NLE Websites -- All DOE Office Websites (Extended Search)

Kentucky Guidance for Ambient Background Assessment Kentucky Guidance for Ambient Background Assessment January 8, 2004 Natural Resources and Environmental Protection Cabinet Introduction This guidance document is intended to assist in comparing site data and background data for sites undergoing environmental assessment. These procedures provide a simplified statistical procedure for determining if the site data is part of the background population. It also provides generic statewide background values for inorganic chemicals that may be used in lieu of collecting site-specific background samples. The statistical procedures may be used for site- specific data or the generic statewide values in Tables 1 and 2. This guidance does not preclude other appropriate statistical comparisons from being made, but rather a simplified screening

149

Microwaves in Biology, Environmental Studies and Chemistry  

Science Conference Proceedings (OSTI)

Oct 30, 2013... using Microwaves, Electric and Magnetic Fields, Ultrasound, Lasers, ... Power under Microwave Irradiated Cultivation: Wataru Nagayoshi1; ...

150

Solar Hydrogen Conversion Background  

E-Print Network (OSTI)

Solar Hydrogen Conversion Background: The photoelectrochemical production of hydrogen has drawn properties In order to develop better materials for solar energy applications, in-depth photoelectrochemical simulated solar irradiance. Hydrogen production experiments are conducted in a sealed aluminum cell

Raftery, Dan

151

Toward a Global Microwave Standard  

Science Conference Proceedings (OSTI)

... Weather and climate uses for microwave remote sensing measurements ... Sensing in PML's Electromagnetics Division, "new data coming from ...

2012-01-31T23:59:59.000Z

152

Microwave | OpenEI  

Open Energy Info (EERE)

Microwave Microwave Dataset Summary Description The following data-set is for a benchmark residential home for all TMY3 locations across all utilities in the US. The data is indexed by utility service provider which is described by its "unique" EIA ID ( Source National Renewable Energy Laboratory Date Released April 05th, 2012 (2 years ago) Date Updated April 06th, 2012 (2 years ago) Keywords AC apartment CFL coffeemaker Computer cooling cost demand Dishwasher Dryer Furnace gas HVAC Incandescent Laptop load Microwave model NREL Residential television tmy3 URDB Data text/csv icon Residential Cost Data for Common Household Items (csv, 14.5 MiB) Quality Metrics Level of Review Some Review Comment Temporal and Spatial Coverage Frequency Annually Time Period License License Open Data Commons Public Domain Dedication and Licence (PDDL)

153

Primordial Helium Abundance from CMB: a constraint from recent observations and a forecast  

E-Print Network (OSTI)

We study a constraint on the primordial helium abundance $Y_p$ from current and future observations of CMB. Using the currently available data from WMAP, ACBAR, CBI and BOOMERANG, we obtained the constraint as $Y_p = 0.25 \\pm 0.10$ at 1$\\sigma$ level. We also provide a forecast for Planck using the Markov Chain Monte Carlo approach. In addition to forecasting the constraint on $Y_p$, we investigate how assumptions for $Y_p$ affect the constraints on the other cosmological parameters.

Ichikawa, Kazuhide; Takahashi, Tomo

2007-01-01T23:59:59.000Z

154

Primordial Helium Abundance from CMB: a constraint from recent observations and a forecast  

E-Print Network (OSTI)

We studied a constraint on the primordial helium abundance Y_p from current and future observations of CMB. Using the currently available data from WMAP, ACBAR, CBI and BOOMERANG, we obtained the constraint as Y_p = 0.25^{+0.10}_{-0.07} at 68% C.L. We also provide a forecast for the Planck experiment using the Markov chain Monte Carlo approach. In addition to forecasting the constraint on Y_p, we investigate how assumptions for Y_p affect constraints on the other cosmological parameters.

Kazuhide Ichikawa; Toyokazu Sekiguchi; Tomo Takahashi

2007-12-28T23:59:59.000Z

155

Unitarity and singular backgrounds  

E-Print Network (OSTI)

We compute the graviton Kaluza-Klein spectrum on a gravity-dilaton background with a naked singularity for all possible boundary conditions at the singularity which are consistent with unitary evolution. We apply methods from non-relativistic quantum mechanics with singular Schr\\"{o}dinger potentials. In general the spectrum contains a tachyon, a sign of instability. Only for a particular boundary condition at the singularity is the spectrum free of tachyons. In this case the lowest-lying graviton mode is massless. We argue that this result will also hold for other backgrounds with similar geometry near the curvature singularity. We complete our study with a brief discussion on radion perturbations and the Higgs mechanism on this singular background.

Nikos Brouzakis; Mariano Quiros

2013-09-13T23:59:59.000Z

156

Cross Terms and Weak Frequency Dependent Signals in the CMB Sky  

E-Print Network (OSTI)

In this paper, we study the amplification of weak frequency dependent signals in the CMB sky due to their cross correlation to intrinsic anisotropies. In particular, we center our attention on mechanisms generating some weak signal, of peculiar spectral behaviour, such as resonant scattering in ionic, atomic or molecular lines, thermal SZ effect or extragalactic foreground emissions, whose typical amplitude (denoted by $\\epsilon$) is sufficiently smaller than the intrinsic CMB fluctuations. We find that all these effects involve either the autocorrelation of anisotropies generated during recombination ($z_{rec}$) or the cross-correlation of those anisotropies with fluctuations arising at some later redshift $z_i$. The degree of this correlation can be computed under the assumption that density fluctuations were generated as standard inflationary models dictate and that they evolved in time according to linear theory. In case that the weak signal is frequency dependent, we show that, by substracting power spectra at different frequencies, it is possible to avoid the limit associated to Cosmic Variance and unveil weaker terms linear in $\\epsilon$. We find that the correlation term shows a different spectral dependence than the squared ($\\propto \\epsilon^2$) term considered usually, making its extraction particularly straightforward for the thermal SZ effect. Furthermore, we find that in most cases the correlation terms are particularly relevant at low multipoles and must be taken into account when characterising the power spectrum associated to weak signals in the large angular scales.

C. Hernandez-Monteagudo; R. A. Sunyaev; MPA; IKI

2004-05-25T23:59:59.000Z

157

Variable frequency microwave furnace system  

DOE Patents (OSTI)

A variable frequency microwave furnace system designed to allow modulation of the frequency of the microwaves introduced into a furnace cavity for testing or other selected applications. The variable frequency microwave furnace system includes a microwave signal generator or microwave voltage-controlled oscillator for generating a low-power microwave signal for input to the microwave furnace. A first amplifier may be provided to amplify the magnitude of the signal output from the microwave signal generator or the microwave voltage-controlled oscillator. A second amplifier is provided for processing the signal output by the first amplifier. The second amplifier outputs the microwave signal input to the furnace cavity. In the preferred embodiment, the second amplifier is a traveling-wave tube (TWT). A power supply is provided for operation of the second amplifier. A directional coupler is provided for detecting the direction of a signal and further directing the signal depending on the detected direction. A first power meter is provided for measuring the power delivered to the microwave furnace. A second power meter detects the magnitude of reflected power. Reflected power is dissipated in the reflected power load. 5 figs.

Bible, D.W.; Lauf, R.J.

1994-06-14T23:59:59.000Z

158

CMB Fluctuations  

NLE Websites -- All DOE Office Websites (Extended Search)

sCDM is standard Cold Dark Matter model with critical density. oCDM is an open universe with Cold Dark Matter model Lambda CDM is a model universe with Cold Dark Matter and enough...

159

Improved Passive Microwave Retrievals of Rain Rate Over Land and Ocean. 1. Algorithm description  

Science Conference Proceedings (OSTI)

A new approach to passive microwave retrievals of precipitation is described that relies on an objective dimensional reduction procedure to filter, normalize, and decorrelate geophysical background noise while retaining the majority of radiometric ...

Grant W. Petty; Ke Li

160

arXiv:astro-ph/0408456v21Dec2004 Measuring Dark Energy Clustering with CMB-Galaxy Correlations  

E-Print Network (OSTI)

arXiv:astro-ph/0408456v21Dec2004 Measuring Dark Energy Clustering with CMB-Galaxy Correlations opportunity to study the dynamics of the dark energy through its large scale clustering properties. Ultimately 3% changes in the gravitational potential or total density fluctuation due to dark energy clustering

Hu, Wayne

Note: This page contains sample records for the topic "microwave background cmb" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

arXiv:astro-ph/0406496v122Jun2004 A Low CMB Quadrupole from Dark Energy Isocurvature Perturbations  

E-Print Network (OSTI)

arXiv:astro-ph/0406496v122Jun2004 A Low CMB Quadrupole from Dark Energy Isocurvature Perturbations, Chicago IL 60637 We explicate the origin of the temperature quadrupole in the adiabatic dark energy model and explore the mechanism by which scale invariant isocurvature dark energy perturbations can lead to its

Hu, Wayne

162

New mechanism for nonlocality from string theory: UV-IR quantum entanglement and its imprints on the CMB  

Science Conference Proceedings (OSTI)

Puff field theories (PFT) arise as the decoupling limits of D3 branes in a Melvin universe and exhibit spatially nonlocal dynamics. Unlike other realizations of nonlocality in string theory, PFTs have full SO(3) rotational symmetry. In this work, we analyze the strongly coupled regime of a PFT through gravitational holography. We find a novel mechanism at the heart of the phenomenon of nonlocality: a quantum entanglement of UV and IR dynamics. In the holographic bulk, this translates to an apparent horizon splitting the space into two regions--with the UV completion of the PFT sitting at the horizon. We unravel this intricate UV-IR setting and devise a prescription for computing correlators that extends the original dictionary of holographic renormalization group. We then implement a cosmological scenario where PFT correlators set the initial conditions for primordial fluctuations. We compute the associated power spectrum of the cosmic microwave background and find that the scenario allows for a distinct stringy signature.

Minton, Gregory; Sahakian, Vatche [Harvey Mudd College, Physics Department, 241 Platt Boulevard, Claremont, California 91711 (United States)

2008-01-15T23:59:59.000Z

163

A MEASUREMENT OF THE CORRELATION OF GALAXY SURVEYS WITH CMB LENSING CONVERGENCE MAPS FROM THE SOUTH POLE TELESCOPE  

Science Conference Proceedings (OSTI)

We compare cosmic microwave background lensing convergence maps derived from South Pole Telescope (SPT) data with galaxy survey data from the Blanco Cosmology Survey, WISE, and a new large Spitzer/IRAC field designed to overlap with the SPT survey. Using optical and infrared catalogs covering between 17 and 68 deg{sup 2} of sky, we detect a correlation between the SPT convergence maps and each of the galaxy density maps at >4{sigma}, with zero correlation robustly ruled out in all cases. The amplitude and shape of the cross-power spectra are in good agreement with theoretical expectations and the measured galaxy bias is consistent with previous work. The detections reported here utilize a small fraction of the full 2500 deg{sup 2} SPT survey data and serve as both a proof of principle of the technique and an illustration of the potential of this emerging cosmological probe.

Bleem, L. E.; Becker, M. R.; Benson, B. A.; Carlstrom, J. E.; Chang, C. L.; Crawford, T. M.; Crites, A. T. [Kavli Institute for Cosmological Physics, University of Chicago, 5640 South Ellis Avenue, Chicago, IL 60637 (United States); Van Engelen, A.; Holder, G. P.; De Haan, T.; Dobbs, M. A. [Department of Physics, McGill University, 3600 Rue University, Montreal, Quebec H3A 2T8 (Canada); Aird, K. A. [University of Chicago, 5640 South Ellis Avenue, Chicago, IL 60637 (United States); Armstrong, R. [National Center for Supercomputing Applications, University of Illinois, 1205 West Clark Street, Urbana, IL 61801 (United States); Ashby, M. L. N. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Biesiadzinski, T. [Department of Physics, University of Michigan, 450 Church Street, Ann Arbor, MI 48109 (United States); Brodwin, M. [Department of Physics and Astronomy, University of Missouri, 5110 Rockhill Road, Kansas City, MO 64110 (United States); Busha, M. T. [Institute for Theoretical Physics, University of Zuerich, Zuerich (Switzerland); Cho, H. M. [NIST Quantum Devices Group, 325 Broadway, Mailcode 817.03, Boulder, CO 80305 (United States); Desai, S. [Department of Physics, Ludwig-Maximilians-Universitaet, Scheinerstr. 1, 81679 Muenchen (Germany); Dore, O. [Division of Physics, Mathematics, and Astronomy, California Institute of Technology, MS 249-17, 1216 East California Blvd., Pasadena, CA 91125 (United States); and others

2012-07-01T23:59:59.000Z

164

Gabor Transforms on the Sphere with Applications to CMB Power Spectrum Estimation  

E-Print Network (OSTI)

The Fourier transform of a dataset apodised with a window function is known as the Gabor transform. In this paper we extend the Gabor transform formalism to the sphere with the intention of applying it to CMB data analysis. The Gabor coefficients on the sphere known as the pseudo power spectrum is studied for windows of different size. By assuming that the pseudo power spectrum coefficients are Gaussian distributed, we formulate a likelihood ansatz using these as input parameters to estimate the full sky power spectrum from a patch on the sky. Since this likelihood can be calculated quickly without having to invert huge matrices, this allows for fast power spectrum estimation. By using the pseudo power spectrum from several patches on the sky together, the full sky power spectrum can be estimated from full-sky or nearly full-sky observations.

Frode K. Hansen; Krzysztof M. Gorski; Eric Hivon

2002-07-22T23:59:59.000Z

165

Preparation of Hydroxyapatite by Microwave Heating  

Science Conference Proceedings (OSTI)

HAP powders were successfully prepared in a 2.45 GHz - 900W multimode home model microwave oven. The HAP powder was prepared by microwave heating ...

166

Microwave sintering of multiple articles  

DOE Patents (OSTI)

Apparatus and method for producing articles of alumina and of alumina and silicon carbide in which the articles are sintered at high temperatures using microwave radiation. The articles are placed in a sintering container which is placed in a microwave cavity for heating. The rates at which heating and cooling take place is controlled.

Blake, Rodger D. (Santa Fe, NM); Katz, Joel D. (Los Alamos, NM)

1993-01-01T23:59:59.000Z

167

Microwave sintering of multiple aritcles  

DOE Patents (OSTI)

Disclosed are apparatus and method for producing articles of alumina and of alumina and silicon carbide in which the articles are sintered at high temperatures using microwave radiation. The articles are placed in a sintering container which is placed in a microwave cavity for heating. The rates at which heating and cooling take place is controlled.

Blake, R.D.; Katz, J.D.

1992-12-31T23:59:59.000Z

168

DNA sequencing using fluorescence background electroblotting membrane  

DOE Patents (OSTI)

A method for the multiplex sequencing on DNA is disclosed which comprises the electroblotting or specific base terminated DNA fragments, which have been resolved by gel electrophoresis, onto the surface of a neutral non-aromatic polymeric microporous membrane exhibiting low background fluorescence which has been surface modified to contain amino groups. Polypropylene membranes are preferably and the introduction of amino groups is accomplished by subjecting the membrane to radio or microwave frequency plasma discharge in the presence of an aminating agent, preferably ammonia. The membrane, containing physically adsorbed DNA fragments on its surface after the electroblotting, is then treated with crosslinking means such as UV radiation or a glutaraldehyde spray to chemically bind the DNA fragments to the membrane through said smino groups contained on the surface thereof. The DNA fragments chemically bound to the membrane are subjected to hybridization probing with a tagged probe specific to the sequence of the DNA fragments. The tagging may be by either fluorophores or radioisotopes. The tagged probes hybridized to said target DNA fragments are detected and read by laser induced fluorescence detection or autoradiograms. The use of aminated low fluorescent background membranes allows the use of fluorescent detection and reading even when the available amount of DNA to be sequenced is small. The DNA bound to the membrances may be reprobed numerous times.

Caldwell, Karin D. (Salt Lake City, UT); Chu, Tun-Jen (Salt Lake City, UT); Pitt, William G. (Orem, UT)

1992-01-01T23:59:59.000Z

169

DNA sequencing using fluorescence background electroblotting membrane  

DOE Patents (OSTI)

A method for the multiplex sequencing on DNA is disclosed which comprises the electroblotting or specific base terminated DNA fragments, which have been resolved by gel electrophoresis, onto the surface of a neutral non-aromatic polymeric microporous membrane exhibiting low background fluorescence which has been surface modified to contain amino groups. Polypropylene membranes are preferably and the introduction of amino groups is accomplished by subjecting the membrane to radio or microwave frequency plasma discharge in the presence of an aminating agent, preferably ammonia. The membrane, containing physically adsorbed DNA fragments on its surface after the electroblotting, is then treated with crosslinking means such as UV radiation or a glutaraldehyde spray to chemically bind the DNA fragments to the membrane through amino groups contained on the surface. The DNA fragments chemically bound to the membrane are subjected to hybridization probing with a tagged probe specific to the sequence of the DNA fragments. The tagging may be by either fluorophores or radioisotopes. The tagged probes hybridized to the target DNA fragments are detected and read by laser induced fluorescence detection or autoradiograms. The use of aminated low fluorescent background membranes allows the use of fluorescent detection and reading even when the available amount of DNA to be sequenced is small. The DNA bound to the membranes may be reprobed numerous times. No Drawings

Caldwell, K.D.; Chu, T.J.; Pitt, W.G.

1992-05-12T23:59:59.000Z

170

ANOMALOUS ANISOTROPIC CROSS-CORRELATIONS BETWEEN WMAP CMB MAPS AND SDSS GALAXY DISTRIBUTION AND IMPLICATIONS ON THE DARK FLOW SCENARIO  

SciTech Connect

We search for the dark flow induced diffuse kinetic Sunyaev-Zel'dovich (kSZ) effect through CMB-galaxy cross-correlation. Such angular correlation is anisotropic, with a unique cos ({theta}{sub DF}) angular dependence, and hence can be distinguished from other components. Here, {theta}{sub DF} is the angle between the opposite dark flow direction and the direction of the sky where the correlation is measured. We analyze the KIAS-VAGC galaxy catalog of SDSS-DR7 and the WMAP seven-year temperature maps, applying an unbiased optimal weighting scheme to eliminate any statistically isotropic components and to enhance the dark flow detection signal. Non-zero weighted cross-correlations are detected at 3.5 {sigma} for the redshift bin z < 0.1 and at 3 {sigma} for the bin 0.1 < z < 0.2, implying the existence of statistically anisotropic components in CMB. However, further analysis does not support the dark flow explanation. The observed directional dependence deviates from the {proportional_to}cos {theta}{sub DF} relation expected, and hence cannot be explained by the presence of a single dark flow, and if the observed cross-correlation is generated by the dark flow induced kSZ effect, the velocity would be too high ({approx}> 6000 km s{sup -1}). We report this work as the first attempt to search for dark flow through weighted CMB-galaxy cross-correlation and to draw the attention on the sources of the detected anomalous CMB-galaxy cross-correlation.

Li Zhigang; Chen Xuelei [Key Laboratory of Optical Astronomy, National Astronomical Observatories, Chinese Academy of Science, Beijing 100012 (China); Zhang Pengjie, E-mail: zgli@bao.ac.cn, E-mail: pjzhang@shao.ac.cn, E-mail: xuelei@cosmology.bao.ac.cn [Key Laboratory for Research in Galaxies and Cosmology, Shang Astronomical Observatory, Nandan Road 80, Shanghai 200030 (China)

2012-10-20T23:59:59.000Z

171

Microwave-driven ultraviolet light sources  

DOE Patents (OSTI)

A microwave-driven ultraviolet (UV) light source is provided. The light source comprises an over-moded microwave cavity having at least one discharge bulb disposed within the microwave cavity. At least one magnetron probe is coupled directly to the microwave cavity.

Manos, Dennis M. (Williamsburg, VA); Diggs, Jessie (Norfolk, VA); Ametepe, Joseph D. (Roanoke, VA)

2002-01-29T23:59:59.000Z

172

Gigatron microwave amplifier  

DOE Patents (OSTI)

An electron tube for achieving high power at high frequency with high efficiency, including an input coupler, a ribbon-shaped electron beam and a traveling wave output coupler. The input coupler is a lumped constant resonant circuit that modulates a field emitter array cathode at microwave frequency. A bunched ribbon electron beam is emitted from the cathode in periodic bursts at the desired frequency. The beam has a ribbon configuration to eliminate limitations inherent in round beam devices. The traveling wave coupler efficiently extracts energy from the electron beam, and includes a waveguide with a slot therethrough for receiving the electron beam. The ribbon beam is tilted at an angle with respect to the traveling wave coupler so that the electron beam couples in-phase with the traveling wave in the waveguide. The traveling wave coupler thus extracts energy from the electron beam over the entire width of the beam.

McIntyre, Peter M. (611 Montclair, College Station, TX 77840)

1993-01-01T23:59:59.000Z

173

Gigatron microwave amplifier  

DOE Patents (OSTI)

An electron tube for achieving high power at high frequency with high efficiency is described, including an input coupler, a ribbon-shaped electron beam and a traveling wave output coupler. The input coupler is a lumped constant resonant circuit that modulates a field emitter array cathode at microwave frequency. A bunched ribbon electron beam is emitted from the cathode in periodic bursts at the desired frequency. The beam has a ribbon configuration to eliminate limitations inherent in round beam devices. The traveling wave coupler efficiently extracts energy from the electron beam, and includes a waveguide with a slot there through for receiving the electron beam. The ribbon beam is tilted at an angle with respect to the traveling wave coupler so that the electron beam couples in-phase with the traveling wave in the waveguide. The traveling wave coupler thus extracts energy from the electron beam over the entire width of the beam.

McIntyre, P.M.

1993-07-13T23:59:59.000Z

174

Paducah Background Factsheet | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Background Factsheet Paducah Background Factsheet Background Fact Sheet Transfer of Depleted Uranium and Subsequent Transactions, May 15, 2012 Paducah Background...

175

VALIDATION OF MICROWAVE HEATING INSTRUCTIONS FOR THE DESTRUCTION OF Salmonella spp. IN MICROWAVEABLE FOODS.  

E-Print Network (OSTI)

??Microwave heating instructions for three products (chicken nuggets, turkey pot-pies and mashed potato) were developed and validated based on end point temperatures using two microwave… (more)

Valenzuela, Carol J

2013-01-01T23:59:59.000Z

176

Study of federal microwave standards  

DOE Green Energy (OSTI)

Present and future federal regulatory processes which may impact the permissible levels of microwave radiation emitted by the SPS Microwave Power Transmission (MPTS) were studied. An historical development of US occupational and public microwave standards includes an overview of Western and East European philosophies of environmental protection and neurophysiology which have led to the current widely differing maximum permissible exposure limits to microwaves. The possible convergence of microwave standards is characterized by a lowering of Western exposure levels while Eastern countries consider standard relaxation. A trend toward stricter controls on activities perceived as harmful to public health is under way as is interest in improving the federal regulatory process. Particularly relevant to SPS is the initiation of long-term, low-level microwave exposure programs. Coupled with new developments in instrumentation and dosimetry, the results from chronic exposure program and population exposure studies could be expected within the next five to ten years. Also discussed is the increasing public concern that rf energy is yet another hazardous environmental agent.

David, L.

1980-08-01T23:59:59.000Z

177

Background  

Science Conference Proceedings (OSTI)

Web-based Tool for Converting Carbon Dioxide Isotope Measurements into Standardized delta–13–C and delta–18–O Values. ...

2013-10-25T23:59:59.000Z

178

Background  

E-Print Network (OSTI)

Cyclic nucleotide-gated (CNG) channels are members of the superfamily of pore loop cation channels that are activated by the binding of cGMP or cAMP. The channels are important cellular switches which transduce changes in intracellular levels of cyclic nucleotides into changes of the membrane potential and the Ca 2+ concentration. CNG channels play a central role in the signal transduction pathways of vision and olfaction. We have studied the physiological significance of a particular member of the CNG channel family, CNGB1. The two splicing variants of CNGB1, termed CNGB1a and CNGB1b, assemble with CNGA1 and CNGA2/4 to form the native tetrameric CNG channels of rod photoreceptors and olfactory neurons, respectively. retinitis pigmentosa [1]. Using a combination of electrophysiologcal

Martin Biel; Stylianos Michalakis; Xiangang Zong; Elvir Becirovic

2009-01-01T23:59:59.000Z

179

Background  

Science Conference Proceedings (OSTI)

BOOK: The Superalloys: Fundamentals and Applications R. C. Reed, Cambridge ... New Messages, Rating, WEB RESOURCE: Handbook of Materials Selection

180

Background:  

NLE Websites -- All DOE Office Websites (Extended Search)

TABLE OF CONTENTS Recommended Browsers for iSupplier Portal Recommended Microsoft Internet Explorer Browser Settings (MSIE) Recommended Firefox Browser Settings Recommended...

Note: This page contains sample records for the topic "microwave background cmb" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Background  

E-Print Network (OSTI)

the International City/County Management Association (IChz4). PTI’s mission is to bring technology to local governments. Through collective research and development efforts in its member jurisdictions, PTI creates and adrances technology-based products, services, and enterprises for all cities and counties. Four active task forces, each composed of members of PTI’s Urban Consortium WC)-which represents fifty of the nation’s largest and most progressive cities and urban counties--drive PTI’s research and commercialization efforts. One of these task forces is the Urban Consortium Energy Task Force (UCETF), which was established to address critical energy needs of urban America.

D Emonstration; Economic; A Nalysis Of; U Rban; C Onsortium

1997-01-01T23:59:59.000Z

182

background  

Science Conference Proceedings (OSTI)

... the environment, and methodologies for tracing life-cycle costs to a ... Global investments in sustainable energy (including wind, solar, and ...

183

BACKGROUND  

Usually results in lowered chemical durability as measured ... F or more inf rmation about the science you see here, please contact: John McCloy, Ph.D.

184

BACKGROUND  

Science Conference Proceedings (OSTI)

... Fax: 301/670-9884. Email: dominique@aeptec.com. John Dunfield. Microvision, Inc. 2203 Airport Way S., Ste. 100. Seattle, WA 98134 USA. ...

1999-02-16T23:59:59.000Z

185

Background  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Patent Rights in the New Independent States (NIS) of the Former Soviet Union for Inventions made by NIS institutes' employeess in the course of or under agreements entered into...

186

Cosmological non-Gaussian signature detection: comparing performance of different statistical tests  

Science Conference Proceedings (OSTI)

Currently, it appears that the best method for non-Gaussianity detection in the cosmic microwave background (CMB) consists in calculating the kurtosis of the wavelet coefficients. We know that wavelet-kurtosis outperforms other methods such as the bispectrum, ... Keywords: cosmological microwave background, cosmology, curvelet, multiscale method, non-Gaussianity detection, wavelet

J. Jin; J.-L. Starck; D. L. Donoho; N. Aghanim; O. Forni

2005-01-01T23:59:59.000Z

187

Difference between Life and Death of Bacterium against Microwave ...  

Science Conference Proceedings (OSTI)

... Electric and Magnetic Fields, Ultrasound, Lasers, and Mechanical Work. ... of Bacterium against Microwave Power under Microwave Irradiated Cultivation.

188

Microwave Off-gas srnlTechBriefp1  

Microwave energy combines with infrared heating ... A modified retail microwave oven requires little space, is compatible with existing electrical ...

189

MAR Background Report MAR Background Report: Indigenous Protest in Brazil  

E-Print Network (OSTI)

MAR Background Report MAR Background Report: Indigenous Protest in Brazil Hundreds of indigenous people demonstrated at the National Congress in Brasilia, capital of Brazil, following the announcement in the 1990s in the midst of extensive protests in Brazil and around the world. On February 8, an indigenous

Milchberg, Howard

190

Background on Quantum Key Distribution  

Science Conference Proceedings (OSTI)

... Background on Quantum Key Distribution. ... If someone, referred to by cryptographers as Eve, tries to eavesdrop on the transmission, she will not ...

2011-08-02T23:59:59.000Z

191

Angola Background - Energy Information Administration  

U.S. Energy Information Administration (EIA)

‹ Countries Angola Last Updated: January 3, 2013 (Notes) Revised: January 8, 2013 (revision) full report Background Angola is the second-largest oil producer in Sub ...

192

Ignition methods and apparatus using microwave energy  

SciTech Connect

An ignition apparatus for a combustor includes a microwave energy source that emits microwave energy into the combustor at a frequency within a resonant response of the combustor, the combustor functioning as a resonant cavity for the microwave energy so that a plasma is produced that ignites a combustible mixture therein. The plasma preferably is a non-contact plasma produced in free space within the resonant cavity spaced away from with the cavity wall structure and spaced from the microwave emitter.

DeFreitas, Dennis Michael (Oxford, NY); Migliori, Albert (Santa Fe, NM)

1997-01-01T23:59:59.000Z

193

Microwave Augmented Fabrication and Evaluation of CNT ...  

Science Conference Proceedings (OSTI)

About this Abstract. Meeting, 2011 TMS Annual Meeting & Exhibition. Symposium , Biological Materials Science. Presentation Title, Microwave Augmented ...

194

Microwavable thermal energy storage material  

DOE Patents (OSTI)

A microwavable thermal energy storage material is provided which includes a mixture of a phase change material and silica, and a carbon black additive in the form of a conformable dry powder of phase change material/silica/carbon black, or solid pellets, films, fibers, moldings or strands of phase change material/high density polyethylene/ethylene-vinyl acetate/silica/carbon black which allows the phase change material to be rapidly heated in a microwave oven. The carbon black additive, which is preferably an electrically conductive carbon black, may be added in low concentrations of from 0.5 to 15% by weight, and may be used to tailor the heating times of the phase change material as desired. The microwavable thermal energy storage material can be used in food serving applications such as tableware items or pizza warmers, and in medical wraps and garments.

Salyer, Ival O. (Dayton, OH)

1998-09-08T23:59:59.000Z

195

Microwavable thermal energy storage material  

DOE Patents (OSTI)

A microwavable thermal energy storage material is provided which includes a mixture of a phase change material and silica, and a carbon black additive in the form of a conformable dry powder of phase change material/silica/carbon black, or solid pellets, films, fibers, moldings or strands of phase change material/high density polyethylene/ethylene vinyl acetate/silica/carbon black which allows the phase change material to be rapidly heated in a microwave oven. The carbon black additive, which is preferably an electrically conductive carbon black, may be added in low concentrations of from 0.5 to 15% by weight, and may be used to tailor the heating times of the phase change material as desired. The microwavable thermal energy storage material can be used in food serving applications such as tableware items or pizza warmers, and in medical wraps and garments. 3 figs.

Salyer, I.O.

1998-09-08T23:59:59.000Z

196

Microwave treatment of vulcanized rubber  

DOE Patents (OSTI)

A process and resulting product is provided in which a vulcanized solid particulate, such as vulcanized crumb rubber, has select chemical bonds broken by microwave radiation. The direct application of microwaves in combination with uniform heating of the crumb rubber renders the treated crumb rubber more suitable for use in new rubber formulations. As a result, larger particle sizes and/or loading levels of the treated crumb rubber can be used in new rubber mixtures to produce recycled composite products with good properties.

Wicks, George G. (Aiken, SC); Schulz, Rebecca L. (Aiken, SC); Clark, David E. (Gainesville, FL); Folz, Diane C. (Gainesville, FL)

2002-07-16T23:59:59.000Z

197

RF & Microwave Systems Group The RF & Microwave Systems  

E-Print Network (OSTI)

for Technology Transfer. Tagging, Tracking, and Locating Systems TTL technologies are on the verge and development (R&D) geared toward supplying robust communications for extreme environments; global tagging, tracking, and locating (TTL) systems; and RF- and microwave- based measurement and processing systems

198

The cross correlation between the 21-cm radiation and the CMB lensing field: a new cosmological signal  

DOE Green Energy (OSTI)

The measurement of Baryon Acoustic Oscillations through the 21-cm intensity mapping technique at redshift z {<=} 4 has the potential to tightly constrain the evolution of dark energy. Crucial to this experimental effort is the determination of the biasing relation connecting fluctuations in the density of neutral hydrogen (HI) with the ones of the underlying dark matter field. In this work I show how the HI bias relevant to these 21-cm intensity mapping experiments can successfully be measured by cross-correlating their signal with the lensing signal obtained from CMB observations. In particular I show that combining CMB lensing maps from Planck with 21-cm field measurements carried out with an instrument similar to the Cylindrical Radio Telescope, this cross-correlation signal can be detected with a signal-to-noise (S/N) ratio of more than 5. Breaking down the signal arising from different redshift bins of thickness {Delta}z = 0.1, this signal leads to constraining the large scale neutral hydrogen bias and its evolution to 4{sigma} level.

Vallinotto, Alberto [Los Alamos National Laboratory

2011-01-01T23:59:59.000Z

199

Low background techniques in XMASS  

SciTech Connect

The XMASS project aims to detect pp and {sup 7}Be solar neutrinos, neutrino-less double beta decay, and dark matter searches using ultra-pure liquid xenon. The first stage of XMASS project is concentrated on dark matter searches using 800 kg liquid xenon detector which requires low background and low threshold. Several techniques applied to XMASS detector for low background will be presented.

Takeda, Atsushi [Kamioka Observatory, ICRR, University of Tokyo, 456 Higashi-Mozumi, Kamioka-cho, Hida, Gifu, 506-1205 (Japan)

2011-04-27T23:59:59.000Z

200

Scanning tip microwave near field microscope  

SciTech Connect

A microwave near field microscope has a novel microwave probe structure wherein the probing field of evanescent radiation is emitted from a sharpened metal tip instead of an aperture or gap. This sharpened tip, which is electrically and mechanically connected to a central electrode, extends through and beyond an aperture in an endwall of a microwave resonating device such as a microwave cavity resonator or a microwave stripline resonator. Since the field intensity at the tip increases as the tip sharpens, the total energy which is radiated from the tip and absorbed by the sample increases as the tip sharpens. The result is improved spatial resolution without sacrificing sensitivity.

Xiang, Xiao-Dong (Alameda, CA); Schultz, Peter G. (Oakland, CA); Wei, Tao (Albany, CA)

1998-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "microwave background cmb" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Microwave scattering from laser spark in air  

Science Conference Proceedings (OSTI)

In this paper, microwave Mie scattering from a laser-induced plasma in atmospheric air is computed. It shows that the scattered microwave transitions from coherent Rayleigh scattering to Mie scattering based on the relative transparency of the laser-induced plasma at the microwave frequency. The microwave penetration in the plasma alters from total transparency to partial shielding due to the sharp increase of the electron number density within the avalanche ionization phase. The transition from Rayleigh scattering to Mie scattering is verified by both the temporal evolution of the scattered microwave and the homogeneity of polar scattering plots.

Sawyer, Jordan; Zhang Zhili [Mechanical, Aerospace and Biomedical Engineering, University of Tennessee, Knoxville, Tennessee 37996 (United States); Shneider, Mikhail N. [Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey 08544 (United States)

2012-09-15T23:59:59.000Z

202

Microwave sintering of boron carbide  

DOE Patents (OSTI)

A method for forming boron carbide into a particular shape and densifying the green boron carbide shape. Boron carbide in powder form is pressed into a green shape and then sintered, using a microwave oven, to obtain a dense boron carbide body. Densities of greater than 95% of theoretical density have been obtained. 1 tab.

Blake, R.D.; Katz, J.D.; Petrovic, J.J.; Sheinberg, H.

1988-06-10T23:59:59.000Z

203

Controlled zone microwave plasma system  

DOE Patents (OSTI)

An apparatus and method for initiating a process gas plasma. A conductive plate having a plurality of conductive fingers is positioned in a microwave applicator. An arc forms between the conductive fingers to initiate the formation of a plasma. A transport mechanism may convey process materials through the plasma. A spray port may be provided to expel processed materials.

Ripley, Edward B. (Knoxville, TN); Seals, Roland D. (Oak Ridge, TN); Morrell, Jonathan S. (Knoxville, TN)

2009-10-20T23:59:59.000Z

204

microwaverpp.dvi  

NLE Websites -- All DOE Office Websites (Extended Search)

microwave microwave background 1 26. COSMIC MICROWAVE BACKGROUND Revised September 2013 by D. Scott (University of British Columbia) and G.F. Smoot (UCB/LBNL). 26.1. Introduction The energy content in radiation from beyond our Galaxy is dominated by the cosmic microwave background (CMB), discovered in 1965 [1]. The spectrum of the CMB is well described by a blackbody function with T = 2.7255 K, this spectral form being one of the main pillars of the hot Big Bang model for the early Universe. The lack of any observed deviations from a blackbody spectrum constrains physical processes over cosmic history at redshifts z ∼ < 10 7 (see earlier versions of this review). All viable cosmological models predict a very nearly Planckian spectrum inside the current observational limits (although that could change with more sensitive spectral experiments in the future [2]). Currently the key CMB observable

205

Bayesian ICA-based source separation of Cosmic Microwave Background by a discrete functional approximation  

E-Print Network (OSTI)

. Salerno, A. Tonazzini, E.E. Kuruoglu, L. Bedini, D. Herranz, and C. Baccigalupi, "Source separation

O'Mahony, Donal E.

206

Measurements of Secodary Cosmic Microwave Background Anisotropies with the South Pole Telescope  

E-Print Network (OSTI)

heat capacity. . . . . . . . . . . . . . . . . . . .like a single lumped heat capacity. Of- ten the physicaloscillations. Adding heat capacity to these devices can

Lueker, Martin Van

2010-01-01T23:59:59.000Z

207

Antenna-coupled Superconducting Bolometers for Observations of the Cosmic Microwave Background Polarization  

E-Print Network (OSTI)

of matter and blackbody radiation expanded and cooledthe already tiny 3 K blackbody radiation. While COBE showed

Myers, Michael James

2010-01-01T23:59:59.000Z

208

Cosmic microwave Background Map-making at the Petascale and Beyond...  

NLE Websites -- All DOE Office Websites (Extended Search)

to extend the analysis algorithms and their implementations to peta-scale high performance computing (HPC) systems and beyond. The most computationally intensive part of the...

209

Measurement of the Cosmic Microwave Background Polarization with the BICEP Telescope at the South Pole  

E-Print Network (OSTI)

the bolometers from electromagnetic interference. The outputthe interference by improving the electromagnetic shield

Takahashi, Yuki David

2010-01-01T23:59:59.000Z

210

A parallel two-level preconditioner for cosmic microwave background map-making  

Science Conference Proceedings (OSTI)

Generalized least square problems with non-diagonal weights arise frequently in an estimation of two dimensional images from data of cosmological as well as astro- or geo- physical observations. As the observational data sets keep growing at Moore's ...

Laura Grigori; Radek Stompor; Mikolaj Szydlarski

2012-11-01T23:59:59.000Z

211

The Origin of the Universe as Revealed Through the Polarization of the Cosmic Microwave Background  

E-Print Network (OSTI)

, Lyman Page, Peter Ade, Alexandre Am- blard, Amjad Ashoorioon, Carlo Baccigalupi, Amedeo Balbi, James

Timbie, Peter

212

Measurements of Secodary Cosmic Microwave Background Anisotropies with the South Pole Telescope  

E-Print Network (OSTI)

S. , Johnson, B. R. , Ade, P. , Balbi, A. , Bock, J. J. ,Polenta, G. , Marinucci, D. , Balbi, A. , de Bernardis, P. ,

Lueker, Martin Van

2010-01-01T23:59:59.000Z

213

Measurements of Secodary Cosmic Microwave Background Anisotropies with the South Pole Telescope  

E-Print Network (OSTI)

Measuring L SQ . . . . . . . . 4.3 Transmission lines: 4K tolike system. . . . Transmission line resonances in the 4Kpoorly matched to the transmission lines connecting them to

Lueker, Martin Van

2010-01-01T23:59:59.000Z

214

Design and Deployment of the POLARBEAR Cosmic Microwave Background Polarization Experiment  

E-Print Network (OSTI)

temperature prole of the weak thermal link ( n ), and thestructure The weak thermal link between the thermistor and

Arnold, Kam Stahly

2010-01-01T23:59:59.000Z

215

Non-Gaussianity in the Cosmic Microwave Background Induced by Dipolar Dark Matter  

E-Print Network (OSTI)

In previous work [L. Blanchet and A. Le Tiec, Phys. Rev. D 80, 023524 (2009)], motivated by the phenomenology of dark matter at galactic scales, a model of dipolar dark matter (DDM) was introduced. At linear order in cosmological perturbations, the dynamics of the DDM was shown to be identical to that of standard cold dark matter (CDM). In this paper, the DDM model is investigated at second order in cosmological perturbation theory. We find that the internal energy of the DDM fluid modifies the curvature perturbation generated by CDM with a term quadratic in the dipole field. This correction induces a new type of non-Gaussianity in the bispectrum of the curvature perturbation with respect to standard CDM. Leaving unspecified the primordial amplitude of the dipole field, which could in principle be determined by a more fundamental description of DDM, we find that, in contrast with usual models of primordial non-Gaussianities, the non-Gaussianity induced by DDM increases with time after the radiation-matter equ...

Blanchet, Luc; Tiec, Alexandre Le; Marsat, Sylvain

2013-01-01T23:59:59.000Z

216

Intercalibrated Passive Microwave Rain Products from the Unified Microwave Ocean Retrieval Algorithm (UMORA)  

Science Conference Proceedings (OSTI)

The Unified Microwave Ocean Retrieval Algorithm (UMORA) simultaneously retrieves sea surface temperature, surface wind speed, columnar water vapor, columnar cloud water, and surface rain rate from a variety of passive microwave radiometers ...

K. A. Hilburn; F. J. Wentz

2008-03-01T23:59:59.000Z

217

Hybrid Microwave Cavity Heat Engine  

E-Print Network (OSTI)

We propose and analyze the use of hybrid microwave cavities as quantum heat engines. A possible realization consists of two macroscopically separated quantum dot conductors coupled capacitively to the fundamental mode of a microwave cavity. We demonstrate that an electrical current can be induced in one conductor through cavity-mediated processes by heating up the other conductor. The heat engine can reach Carnot efficiency with optimal conversion of heat to work. When the system delivers the maximum power, the efficiency can be a large fraction of the Carnot efficiency. The heat engine functions even with moderate electronic relaxation and dephasing in the quantum dots. We provide detailed estimates for the electrical current and output power using realistic parameters.

Christian Bergenfeldt; Peter Samuelsson; Björn Sothmann; Christian Flindt; Markus Büttiker

2013-07-18T23:59:59.000Z

218

Microwave-enhanced chemical processes  

DOE Patents (OSTI)

A process for disposal of toxic wastes including chlorinated hydrocarbons, comprising, establishing a bed of non-metallic particulates having a high dielectric loss factor. Effecting intimate contact of the particulates and the toxic wastes at a temperature in excess of about 400.degree. C. in the presence of microwave radiation for a time sufficient to break the hydrocarbon chlorine bonds and provide detoxification values in excess of 80 and further detoxifying the bed followed by additional disposal of toxic wastes.

Varma, Ravi (Hinsdale, IL)

1990-01-01T23:59:59.000Z

219

Microwave assisted hard rock cutting  

DOE Patents (OSTI)

An apparatus for the sequential fracturing and cutting of subsurface volume of hard rock (102) in the strata (101) of a mining environment (100) by subjecting the volume of rock to a beam (25) of microwave energy to fracture the subsurface volume of rock by differential expansion; and , then bringing the cutting edge (52) of a piece of conventional mining machinery (50) into contact with the fractured rock (102).

Lindroth, David P. (Apple Valley, MN); Morrell, Roger J. (Bloomington, MN); Blair, James R. (Inver Grove Heights, MN)

1991-01-01T23:59:59.000Z

220

Microwave Tokamak Experiment: Overview and status  

SciTech Connect

The Microwave Tokamak Experiment, now under construction at the Laboratory, will use microwave heating from a free-electron laser. The intense microwave pulses will be injected into the tokamak to realize several goals, including a demonstration of the effects of localized heat deposition within magnetically confined plasma, a better understanding of energy confinement in tokamaks, and use of the new free-electron laser technology for plasma heating. 3 figs., 3 tabs.

1990-05-01T23:59:59.000Z

Note: This page contains sample records for the topic "microwave background cmb" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Process for microwave sintering boron carbide  

DOE Patents (OSTI)

A method of microwave sintering boron carbide comprises leaching boron carbide powder with an aqueous solution of nitric acid to form a leached boron carbide powder. The leached boron carbide powder is coated with a glassy carbon precursor to form a coated boron carbide powder. The coated boron carbide powder is consolidated in an enclosure of boron nitride particles coated with a layer of glassy carbon within a container for microwave heating to form an enclosed coated boron carbide powder. The enclosed coated boron carbide powder is sintered within the container for microwave heating with microwave energy.

Holcombe, C.E.; Morrow, M.S.

1993-10-12T23:59:59.000Z

222

Microwave Application to Environmental Problems : Model ...  

Science Conference Proceedings (OSTI)

Difference between Life and Death of Bacterium against Microwave Power under ... Sintering and Plastic Deformation of Ceramics under Pulsed Electric Current.

223

Application of Microwave Heating for Reduction of ...  

Science Conference Proceedings (OSTI)

Difference between Life and Death of Bacterium against Microwave Power under ... Sintering and Plastic Deformation of Ceramics under Pulsed Electric Current.

224

Rapid Baking of Friction Material with Microwaves  

Science Conference Proceedings (OSTI)

The curing is followed by baking in electrical oven with multistage heating for ... Difference between Life and Death of Bacterium against Microwave Power under

225

Investigation on Microstructural Characterization of Microwave ...  

Science Conference Proceedings (OSTI)

... substrate have been developed through home microwave oven at frequency ... On the Interrelationship of Applied Fields and Heating Rates during Electric ...

226

Innovative Microwave Technology - Energy Innovation Portal  

Hadron Technologies, Inc. has signed an exclusive license for a Hybrid Microwave and Off-Gas Treatment System ... within the commercial and ... Buildi ...

227

Microwave Spectra of Molecules of Astrophysical Interest. ...  

Science Conference Proceedings (OSTI)

Page 1. Microwave Spectra of Molecules of Astrophysical Interest. XXVI. Acetic Acid „CH3COOH… ... 100 3. Acetic Acid Spectral Tables. . . . . ...

2012-04-17T23:59:59.000Z

228

New Energy Efficiency Standards for Microwave Ovens to Save Consumers...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

New Energy Efficiency Standards for Microwave Ovens to Save Consumers on Energy Bills New Energy Efficiency Standards for Microwave Ovens to Save Consumers on Energy Bills May 31,...

229

EETD Assists in Analysis of Microwave Oven Energy Efficiency...  

NLE Websites -- All DOE Office Websites (Extended Search)

EETD Assists in Analysis of Microwave Oven Energy Efficiency Standard June 2013 The Department of Energy recently announced new energy efficiency standards for microwave ovens....

230

Near-Instantaneous Microwave Heating and Cooling for Microfluidic ...  

home \\ technologies \\ microwave heating of microfluidics. Technologies: Ready-to-Sign Licenses: Software: Patents: Near-Instantaneous Microwave Heating and Cooling ...

231

APS USER TRAINING HISTORY Background  

NLE Websites -- All DOE Office Websites (Extended Search)

USER TRAINING HISTORY USER TRAINING HISTORY Background The User Program Division Director has delegated to the CATs the authority to authorize the conduct of experiments because the CATs have accepted responsibility for: * identifying and evaluating the hazards posed by the experiment, * specifying controls appropriate to the hazards, and * verifying that controls are in place. One form of hazard control frequently made mandatory by law and laboratory policy is worker knowledge. The accepted means of verifying that a worker has the required knowledge is ensuring that the worker has completed appropriate training. With CAT input, the APS has developed the APS User Training History. This web-based tool enables designated CAT personnel to examine data characterizing ES&H training courses

232

Low background aspects of GERDA  

Science Conference Proceedings (OSTI)

The GERDA experiment operates bare Germanium diodes enriched in 76 Ge in an environment of pure liquid argon to search for neutrinoless double beta decay. A very low radioactive background is essential for the success of the experiment. We present here the research done in order to remove radio?impurities coming from the liquid argon the stainless steel cryostat and the front?end electronics. We found that liquid argon can be purified efficiently from 222 Rn . The main source of 222 Rn in GERDA is the cryostat which emanates about 55 mBq. A thin copper shroud in the center of the cryostat was implemented to prevent radon from approaching the diodes. Gamma ray screening of radio?pure components for front?end electronics resulted in the development of a pre?amplifier with a total activity of less than 1? mBq ? 228 Th .

Hardy Simgen; The GERDA collaboration

2011-01-01T23:59:59.000Z

233

Method of sintering materials with microwave radiation  

DOE Patents (OSTI)

A method of sintering ceramic materials following: A compacted article comprising inorganic particles coated with carbon is provided, the carbon providing improved microwave coupling. The compacted article is then heated by microwave radiation to a temperature and for a period of time sufficient to sinter the compacted article.

Kimrey, Jr., Harold D. (Knoxville, TN); Holcombe, Jr., Cressie E. (Farragut, TN); Dykes, Norman L. (Oak Ridge, TN)

1994-01-01T23:59:59.000Z

234

Multi-wall carbon nanotubes in microwaves  

Science Conference Proceedings (OSTI)

The electromagnetic (EM) response of multi-wall carbon nanotubes (MWCNT) prepared by chemical vapor decomposition (CVD) method has been analyzed in the microwave frequency range. EM absorption properties of MWCNT depend on their medium diameter related ... Keywords: carbon nanotube, coating, electromagnetic absorption, microwave

S. Moseenkov; V. Kuznetsov; A. Usoltseva; I. Mazov; A. Ischenko; T. Buryakov; O. Anikeeva; A. Romanenko; P. Kuzhir; D. Bychenok; K. Batrakov; S. Maksimenko

2009-02-01T23:59:59.000Z

235

Microwave-triggered laser switch  

DOE Patents (OSTI)

A high-repetition rate switch is described for delivering short duration, high-powered electrical pulses from a pulsed-charged dc power supply. The present invention utilizes a microwave-generating device such as a magnetron that is capable of producing high-power pulses at high-pulse repetition rates and fast-pulse risetimes for long periods with high reliability. The rail-gap electrodes provide a large surface area that reduces induction effects and minimizes electrode erosion. Additionally, breakdown is initiated in a continuous geometric fashion that also increases operating lifetime of the device.

Piltch, M.S.

1982-05-19T23:59:59.000Z

236

Microwave-enhanced chemical processes  

DOE Patents (OSTI)

A process is disclosed for the disposal of toxic wastes including chlorinated hydrocarbons, comprising, establishing a bed of non-metallic particulates having a high dielectric loss factor. Intimate contact of the particulates and the toxic wastes at a temperature in excess of about 400 C in the presence of microwave radiation for a time sufficient breaks the hydrocarbon chlorine bonds. Detoxification values in excess of 80 are provided and further detoxification of the bed is followed by additional disposal of toxic wastes. 1 figure.

Varma, R.

1990-06-19T23:59:59.000Z

237

Microwave-enhanced chemical processes  

DOE Patents (OSTI)

This invention pertains to a process for disposal of toxic wastes including chlorinated hydrocarbons, comprising, establishing a bed of non-metallic particulates having a high dielectric loss factor. Effecting intimate contact of the particulates and the toxic wastes at a temperature in excess of about 400{degree}C. In the presence of microwave radiation for a time sufficient to break the hydrocarbon chlorine bonds and provide detoxification values in excess of 80 and further detoxifying the bed followed by additional disposal of toxic wastes.

Varma, R.

1988-09-15T23:59:59.000Z

238

Microwave-triggered laser switch  

DOE Patents (OSTI)

A high-repetition rate switch for delivering short duration, high-power electrical pulses from a pulsed-charged dc power supply. The present invention utilizes a microwave-generating device such as a magnetron that is capable of producing high-power pulses at high-pulse repetition rates and fast-pulse risetimes for long periods with high reliability. The rail-gap electrodes provide a large surface area that reduces induction effects and minimizes electrode erosion. Additionally, breakdown is initiated in a continuous geometric fashion that also increases operating lifetime of the device.

Piltch, Martin S. (Los Alamos, NM)

1984-01-01T23:59:59.000Z

239

Tandem microwave waste remediation and decontamination system  

DOE Patents (OSTI)

The invention discloses a tandem microwave system consisting of a primary chamber in which microwave energy is used for the controlled combustion of materials. A second chamber is used to further treat the off-gases from the primary chamber by passage through a susceptor matrix subjected to additional microwave energy. The direct microwave radiation and elevated temperatures provide for significant reductions in the qualitative and quantitative emissions of the treated off gases. The tandem microwave system can be utilized for disinfecting wastes, sterilizing materials, and/or modifying the form of wastes to solidify organic or inorganic materials. The simple design allows on-site treatment of waste by small volume waste generators.

Wicks, George G. (North Aiken, SC); Clark, David E. (Gainesville, FL); Schulz, Rebecca L. (Gainesville, FL)

1999-01-01T23:59:59.000Z

240

Microwave generated plasma light source apparatus  

SciTech Connect

A microwave generated plasma light source including a microwave generator, a microwave cavity having a light reflecting member forming at least a portion of the cavity, and a member transparent to light and opaque to microwaves disposed across an opening of the cavity opposite the feeding opening through which the microwave generator is coupled. An electrodeless discharge bulb is disposed at a position in the cavity such that the cavity operates as a resonant cavity at least when the bulb is emitting light. In the bulb is encapsulated at least one discharge light emissive substance. The bulb has a shape and is sufficiently small that the bulb acts substantially as a point light source.

Yoshizawa, K.; Ito, H.; Kodama, H.; Komura, H.; Minowa, Y.

1985-02-05T23:59:59.000Z

Note: This page contains sample records for the topic "microwave background cmb" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

A Microwave Thruster for Spacecraft Propulsion  

DOE Green Energy (OSTI)

This presentation describes how a microwave thruster can be used for spacecraft propulsion. A microwave thruster is part of a larger class of electric propulsion devices that have higher specific impulse and lower thrust than conventional chemical rocket engines. Examples of electric propulsion devices are given in this presentation and it is shown how these devices have been used to accomplish two recent space missions. The microwave thruster is then described and it is explained how the thrust and specific impulse of the thruster can be measured. Calculations of the gas temperature and plasma properties in the microwave thruster are discussed. In addition a potential mission for the microwave thruster involving the orbit raising of a space station is explored.

Chiravalle, Vincent P [Los Alamos National Laboratory

2012-07-23T23:59:59.000Z

242

Motion detection in complex and dynamic backgrounds  

Science Conference Proceedings (OSTI)

For the detection of moving objects, background subtraction methods are widely used. In case the background changes, we need to update the background in real-time for the reliable detection of foreground objects. An adaptive Gaussian mixture model (GMM) ...

Daeyong Park; Junbeom Kim; Jaemin Kim; Seongwon Cho; Sun-Tae Chung

2006-12-01T23:59:59.000Z

243

Recombination Softening and Reheating of the Cosmic Plasma  

E-Print Network (OSTI)

The atomic recombination process leads to a softening of the matter equation of state as reflected by a reduced generalized adiabatic index, with accompanying heat release. We study the effects of this recombination softening and reheating of the cosmic plasma on the ionization history, visibility function, Cold Dark Matter (CDM) transfer function, and the Cosmic Microwave Background (CMB) spectra. The resulting modifications of the CMB spectra are not negligible and should be implemented when data with higher accuracy are analysed.

Leung, P K; Chu, M C; Leung, Po Kin; Chan, Chi-Wang; Chu, Ming-Chung

2004-01-01T23:59:59.000Z

244

Solar Background Document 5 | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

5 Solar Background Document 5 Graph illustrating Chinese Development Bank financing to Chinese solar companies. Solar Background Document 5.pdf More Documents & Publications Solar...

245

Solar Background Document 7 | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Solar Background Document 7 Solar Background Document 7 Chart comparing global solar market in 2009 with the market today, illustrating the changing market conditions that Solyndra...

246

POLARIZATION OF THE COSMIC BACKGROUND RADIATION  

E-Print Network (OSTI)

Galactic Synchrotron Radiation at 33 GHz NOIiWNPQaa s x s sthe Cosmic Background Radiation Philip Michael Lubin Spacethe Cosmic Background Radiation. The ground-based experiment

Lubin, Philip Lubin

2010-01-01T23:59:59.000Z

247

Solar Background Document 6 | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Background Document 6 Graph illustrating solar cell production in the United States and China from 2002 to 2010. Solar Background Document 6.pdf More Documents & Publications Solar...

248

Microwave combustion and sintering without isostatic pressure  

SciTech Connect

In recent years interest has grown rapidly in the application of microwave energy to the processing of ceramics, composites, polymers, and other materials. Advances in the understanding of microwave/materials interactions will facilitate the production of new ceramic materials with superior mechanical properties. One application of particular interest is the use of microwave energy for the mobilization of uranium for subsequent redeposition. Phase III (FY98) will focus on the microwave assisted chemical vapor infiltration tests for mobilization and redeposition of radioactive species in the mixed sludge waste. Uranium hexachloride and uranium (IV) borohydride are volatile compounds for which the chemical vapor infiltration procedure might be developed for the separation of uranium. Microwave heating characterized by an inverse temperature profile within a preformed ceramic matrix will be utilized for CVI using a carrier gas. Matrix deposition is expected to commence from the inside of the sample where the highest temperature is present. The preform matrix materials, which include aluminosilicate based ceramics and silicon carbide based ceramics, are all amenable to extreme volume reduction, densification, and vitrification. Important parameters of microwave sintering such as frequency, power requirement, soaking temperature, and holding time will be investigated to optimize process conditions for the volatilization of uranyl species using a reactive carrier gas in a microwave chamber.

Ebadian, M.A.

1998-01-01T23:59:59.000Z

249

Special Sensor Microwave/Imager (SSM/I) and Special Sensor Microwave Imager  

NLE Websites -- All DOE Office Websites (Extended Search)

Special Sensor Microwave/Imager (SSM/I) and Special Sensor Microwave Imager Special Sensor Microwave/Imager (SSM/I) and Special Sensor Microwave Imager Sounder (SSMIS) Global Gridded Products Agriculture Community Menu DATA APPS EVENTS DEVELOPER STATISTICS COLLABORATE ABOUT Agriculture You are here Data.gov » Communities » Agriculture » Data Special Sensor Microwave/Imager (SSM/I) and Special Sensor Microwave Imager Sounder (SSMIS) Global Gridded Products Dataset Summary Description The SSM/I products are useful for evaluating the mean climate state, it's interannual and seasonal variations, and the detection of anomalies associated with ENSO and regional climatic variations. The Hydrology Team has assembled a time series of the entire SSM/I archive, now entering it's 16th year, which includes data from July 1987 to the present. Monthly average products are produced for precipitation, cloud liquid water, total precipitable water, snow cover, sea-ice cover, and oceanic surface wind speed.

250

Large-Angular-Scale Anisotropy in the Cosmic Background Radiation  

DOE R&D Accomplishments (OSTI)

We report the results of an extended series of airborne measurements of large-angular-scale anisotropy in the 3 K cosmic background radiation. Observations were carried out with a dual-antenna microwave radiometer operating at 33 GHz (.089 cm wavelength) flown on board a U-2 aircraft to 20 km altitude. In eleven flights, between December 1976 and May 1978, the radiometer measured differential intensity between pairs of directions distributed over most of the northern hemisphere with an rms sensitivity of 47 mK Hz{sup 1?}. The measurements how clear evidence of anisotropy that is readily interpreted as due to the solar motion relative to the sources of the radiation. The anisotropy is well fit by a first order spherical harmonic of amplitude 360{+ or -}50km sec{sup -1} toward the direction 11.2{+ or -}0.5 hours of right ascension and 19 {+ or -}8 degrees declination. A simultaneous fit to a combined hypotheses of dipole and quadrupole angular distributions places a 1 mK limit on the amplitude of most components of quadrupole anisotropy with 90% confidence. Additional analysis places a 0.5 mK limit on uncorrelated fluctuations (sky-roughness) in the 3 K background on an angular scale of the antenna beam width, about 7 degrees.

Gorenstein, M. V.; Smoot, G. F.

1980-05-00T23:59:59.000Z

251

Planar slot coupled microwave hybrid  

DOE Patents (OSTI)

A symmetrical 180.degree. microwave hybrid is constructed by opening a slot line in a ground plane below a conducting strip disposed on a dielectric substrate, creating a slot coupled conductor. Difference signals propagating on the slot coupled conductor are isolated on the slot line leaving sum signals to propagate on the microstrip. The difference signal is coupled from the slot line onto a second microstrip line for transmission to a desired location. The microstrip branches in a symmetrical fashion to provide the input/output ports of the 180.degree. hybrid. The symmetry of the device provides for balance and isolation between sum and difference signals, and provides an advantageous balance between the power handling capabilities and the bandwidth of the device.

Petter, Jeffrey K. (Williston, VT)

1991-01-01T23:59:59.000Z

252

hepreqrev.pptx  

NLE Websites -- All DOE Office Websites (Extended Search)

Microwave Background Microwave Background Data Analysis Julian Borrill Computational Cosmology Center, LBNL Space Sciences Laboratory, UCB A History Of The Universe Planck CMB Science * Past: - Existence => evidence of Big Bang over Steady State - Temperature anisotropies => fundamental parameters of cosmology, complementary constraints (SN1a) * Present: - Temperature & E-mode polarization anisotropies => precision cosmology, complementary constraints (DE) * Future: - B-mode polarization anisotropies => measurement of lensing potential, evidence of & constraints on Inflation 2 Nobel Prizes awarded, 1 supported, 1 anticipated! The CMB Data Challenge * Extracting fainter signals (polarization, high resolution) from the data requires: - larger data volumes to provide higher signal-to-noise.

253

Determining foreground contamination in cosmic microwavebackground observations: Diffuse Galactic emission in the MAXIMA-Ifield  

Science Conference Proceedings (OSTI)

Observations of the cosmic microwave background (CMB) can be contaminated by diffuse foreground emission from sources such as Galactic dust and synchrotron radiation. In these cases, the morphology of the contaminating source is known from observations at different frequencies, but not its amplitude at the frequency of interest for the CMB. We develop a technique for accounting for the effects of such emission in this case, and for simultaneously estimating the foreground amplitude in the CMB observations. We apply the technique to CMB data from the MAXIMA-1 experiment, using maps of Galactic dust emission from combinations of IRAS and DIRBE observations, as well as compilations of Galactic synchrotron emission observations. The spectrum of the dust emission over the 150-450 GHz observed by MAXIMA is consistent with preferred models, but the effect on CMB power spectrum observations is negligible.

Jaffe, A.H.; Balbi, A.; Bond, J.R.; Borrill, J.; Ferreira, P.G.; Finkbeiner, D.; Hanany, S.; Lee, A.T.; Rabii, B.; Richards, P.L.; Smoot,G.F.; Stompor, R.; Winant, C.D.; Wu, J.H.P.

2003-01-05T23:59:59.000Z

254

Going to the End of the Earth to Learn About the Beginning of the Universe  

SciTech Connect

The cosmic microwave background (CMB) is revolutionizing our understanding of the Universe. The CMB is the most powerful piece of evidence that we live in a geometrically flat Universe, dominated by cold dark matter and dark energy. Even with this basic cosmological model established, there are still many outstanding questions: What is dark energy? What is the sum of the neutrino masses? Are there unknown particle species that we can detect cosmologically? Did Inflation happen? I will review the history of measurements of the CMB; what have they told us so far, and how the South Pole has developed into the premier site for observations of the CMB. Finally, I will discuss new measurements and cosmological results from the South Pole Telescope, a 10-meter diameter telescope that is making precision measurements of the temperature and polarization anisotropy of the CMB.

Benson, Bradford [University of Chicago

2013-02-06T23:59:59.000Z

255

Modulated microwave microscopy and probes used therewith  

Science Conference Proceedings (OSTI)

A microwave microscope including a probe tip electrode vertically positionable over a sample and projecting downwardly from the end of a cantilever. A transmission line connecting the tip electrode to the electronic control system extends along the cantilever and is separated from a ground plane at the bottom of the cantilever by a dielectric layer. The probe tip may be vertically tapped near or at the sample surface at a low frequency and the microwave signal reflected from the tip/sample interaction is demodulated at the low frequency. Alternatively, a low-frequency electrical signal is also a non-linear electrical element associated with the probe tip to non-linearly interact with the applied microwave signal and the reflected non-linear microwave signal is detected at the low frequency. The non-linear element may be semiconductor junction formed near the apex of the probe tip or be an FET formed at the base of a semiconducting tip.

Lai, Keji; Kelly, Michael; Shen, Zhi-Xun

2012-09-11T23:59:59.000Z

256

Beamfilling Errors in Passive Microwave Rainfall Retrievals  

Science Conference Proceedings (OSTI)

There are currently large numbers of rainfall retrieval algorithms based upon passive microwave radiances. Most of these algorithms are physically based in that they use explicit physical assumptions to derive relationships between brightness ...

Christian Kummerow

1998-04-01T23:59:59.000Z

257

Satellite Microwave Surface Observations in Tropical Cyclones  

Science Conference Proceedings (OSTI)

Sea surface estimates of local winds, waves, and rain-rate conditions are crucial to complement infrared/visible satellite images in estimating the strength of tropical cyclones (TCs). Satellite measurements at microwave frequencies are thus key ...

Yves Quilfen; Bertrand Chapron; Jean Tournadre

2010-02-01T23:59:59.000Z

258

Chemical vapor infiltration using microwave energy  

DOE Patents (OSTI)

This invention is comprised of a method for producing reinforced ceramic composite articles by means of chemical vapor infiltration and deposition in which an inverted temperature gradient is utilized. Microwave energy is the source of heat for the process.

Devlin, D.J.; Currier, R.P.; Laia, J.R.; Barbero, R.S.

1992-12-31T23:59:59.000Z

259

Detection of contraband using microwave radiation  

DOE Patents (OSTI)

The present invention relates to a method and system for using microwave radiation to detect contraband hidden inside of a non-metallic container, such as a pneumatic vehicle tire. The method relies on the attenuation, retardation, time delay, or phase shift of microwave radiation as it passes through the container plus the contraband. The method is non-invasive, non-destructive, low power, and does not require physical contact with the container.

Toth, Richard P. (Albuquerque, NM); Loubriel, Guillermo M. (Albuquerque, NM); Bacon, Larry D. (Albuquerque, NM); Watson, Robert D. (Tijeras, NM)

2002-01-01T23:59:59.000Z

260

Forecasts for CMB ?- and i-type spectral distortion constraints on the primordial power spectrum on scales 8 < k < 10^4 Mpc^-1 with the future Pixie-like experiments  

E-Print Network (OSTI)

Silk damping at redshifts 1.5 x 10^4 < z < 2 x 10^6 erases CMB anisotropies on scales corresponding to the comoving wavenumbers 8 < k < 10^4 Mpc^-1 (10^5 < \\ell < 10^8). This dissipated energy is gained by the CMB monopole, creating distortions from a blackbody in the CMB spectrum of the \\mu-type and the i-type. We study, using Fisher matrices, the constraints we can get from measurements of these spectral distortions on the primordial power spectrum from future experiments such as Pixie, and how these constraints change as we change the frequency resolution and the sensitivity of the experiment. We show that the additional information in the shape of the $i$-type distortions, in combination with the \\mu-type distortions, allows us to break the degeneracy between the amplitude and the spectral index of the power spectrum on these scales and leads to much tighter constraints. We quantify the information contained in both the \\mu-type distortions and the i-type distortions taking into account the partial degeneracy with the y-type distortions and the temperature of the blackbody part of the CMB. We also calculate the constraints possible on the primordial power spectrum when the spectral distortion information is combined with the CMB anisotropies measured by the WMAP, SPT, ACT and Planck experiments.

Rishi Khatri; Rashid A. Sunyaev

2013-03-28T23:59:59.000Z

Note: This page contains sample records for the topic "microwave background cmb" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Microwave emissions from police radar  

E-Print Network (OSTI)

The purpose of this study was to evaluate police officers exposures to microwaves emitted by traffic radar units at the ocular and testicular level. Additionally, comparisons were made of the radar manufacturers published maximum power density specifications and actual measured power densities taken at the antenna face of those units. Four different speed enforcement agencies and one transportation research institute provided fifty four different radar units for evaluation. Of those units, nine dash mounted. five rear mounted, and three hand held models were included. During this study, only four of the 986 measurements taken exceeded the American National Standards Institute(ANSI) limit of 5 MW/CM2 , and none exceeded the American Conference of Governmental Industrial Hygienists(ACGIH), Institute of Electrical and Electronic Engineers(IEEE), or Occupational Safety and Health Administration(OSHA) standard of 10 MW/CM2 . None of the 812 measurements taken at the officers seated ocular and testicular positions exceeded .04 MW/CM2. In fact, the highest reading observed in the drivers' position was .034 MW/CM2 taken at the 5th percentile testicular level, less than 1% of the lowest current safety standard. Because of the confusion that exists in the medical and scientific communities concerning non-ionizing radiation, the extent of health risks associated with long term exposure to police radar is not yet known. Until science has indisputably proven that long term, low power exposure is not harmful, it is recommended that police departments take steps to limit officer exposure. There are several ways that police departments can limit exposure cheaply and with minimal effort. The purchasing department should first consider radar units with the lowest published maximum power densities. New hand held radar units should not be purchased because they leave open the opportunity for operators to place their bodies in the radar beam path. Purchasing units whose antennae mount outside the patrol vehicle will also lower exposure to microwaves. Finally, training that stresses the importance of using the radar units' stand-by mode when not actually monitoring traffic will further limit exposure.

Fink, John Michael

1994-01-01T23:59:59.000Z

262

An Improved Microwave Radiative Transfer Model for Tropical Oceanic Precipitation  

Science Conference Proceedings (OSTI)

In preparation for the launch of TRMM, new algorithms must be created that take advantage of the combined data from radar and microwave radiometers that will be on board the satellite. A microwave radiative transfer algorithm with a one-...

Jeffrey R. Tesmer; Thomas T. Wilheit

1998-05-01T23:59:59.000Z

263

A Statistical Modeling Approach to Passive Microwave Rainfall Retrieval  

Science Conference Proceedings (OSTI)

A new empirical algorithm for retrieving rainfall rates from passive microwave (particularly Special Sensor Microwave/Imager) data is presented. Errors caused by spatial and temporal variation of surface temperature, emissivity, and atmospheric ...

Douglas M. Smith; Dominic R. Kniveton; Eric C. Barrett

1998-02-01T23:59:59.000Z

264

A Method for Combining Passive Microwave and Infrared Rainfall Observations  

Science Conference Proceedings (OSTI)

Passive microwave observations of rainfall offer the ability to obtain very accurate instantaneous estimates of rainfall. Because passive microwave instruments are confined to polar-orbiting satellites, however, such estimates must interpolate ...

Christian Kummerow; Louis Giglio

1995-02-01T23:59:59.000Z

265

Ice Water Path Estimation and Characterization Using Passive Microwave Radiometry  

Science Conference Proceedings (OSTI)

Microwave emission emerging from a precipitating cloud top and lying in a radiometer's field of view represents the culmination of a complex interaction between emitted microwave radiation and its ongoing extinction through overlapping regions of ...

J. Vivekanandan; J. Turk; V. N. Bringi

1991-10-01T23:59:59.000Z

266

A Passive Microwave Algorithm for Tropical Oceanic Rainfall  

Science Conference Proceedings (OSTI)

This study discusses a rainfall algorithm utilizing six channels of microwave radiance data from the Nimbus-7 Scanning Multifrequency Microwave Radiometer. The algorithm is intended for short-term climate studies over the ocean at low latitudes. ...

Barry B. Hinton; William S. Olson; David W. Martin; Brian Auvine

1992-12-01T23:59:59.000Z

267

Some Comments on Passive Microwave Measurement of Rain  

Science Conference Proceedings (OSTI)

It is argued that because microwave radiation interacts much more strongly with hydrometeors than with cloud particles, microwave measurements from space offer a significant chance of making global precipitation estimates. Over oceans, passive ...

Thomas T. Wilheit

1986-10-01T23:59:59.000Z

268

Passive-Microwave-Enhanced Statistical Hurricane Intensity Prediction Scheme  

Science Conference Proceedings (OSTI)

The formulation and testing of an enhanced Statistical Hurricane Intensity Prediction Scheme (SHIPS) using new predictors derived from passive microwave imagery is presented. Passive microwave imagery is acquired for tropical cyclones in the ...

Thomas A. Jones; Daniel Cecil; Mark DeMaria

2006-08-01T23:59:59.000Z

269

An Observationally Generated A Priori Database for Microwave Rainfall Retrievals  

Science Conference Proceedings (OSTI)

The combination of active and passive microwave sensors on board the Tropical Rainfall Measuring Mission (TRMM) satellite have been used to construct observationally constrained databases of precipitation profiles for use in passive microwave ...

Christian D. Kummerow; Sarah Ringerud; Jody Crook; David Randel; Wesley Berg

2011-02-01T23:59:59.000Z

270

Microwave Heating, Energy and Environment - Programmaster.org  

Science Conference Proceedings (OSTI)

Mar 7, 2013 ... Microwave Reflection Loss of Ferric Oxide: Zhiwei Peng1; ... heat rapidly by microwave (MW) irradiation generating plasma during oxidation of surfaces. .... Co-Gasification Behavior of Metallurgical Coke with High and Low ...

271

Parametric Rainfall Retrieval Algorithms for Passive Microwave Radiometers  

Science Conference Proceedings (OSTI)

A methodology is described to construct fully parametric rainfall retrieval algorithms for a variety of passive microwave sensors that exist today and are planned for the future. The Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (...

Dong-Bin Shin; Christian Kummerow

2003-10-01T23:59:59.000Z

272

Microwave quantum logic spectroscopy and control of molecular ions  

E-Print Network (OSTI)

A general method for rotational microwave spectroscopy and control of polar molecular ions via direct microwave addressing is considered. Our method makes use of spatially varying ac Stark shifts, induced by far off-resonant, ...

Drewsen, M

273

Satellite Rainfall Estimation Using Combined Passive Microwave and Infrared Algorithms  

Science Conference Proceedings (OSTI)

The development of a combined infrared and passive microwave satellite rainfall estimation technique is outlined. Infrared data from geostationary satellites are combined with polar-orbiting passive microwave estimates to provide 30-min rainfall ...

Chris Kidd; Dominic R. Kniveton; Martin C. Todd; Tim J. Bellerby

2003-12-01T23:59:59.000Z

274

Global estimation of precipitation using opaque microwave bands  

E-Print Network (OSTI)

This thesis describes the use of opaque microwave bands for global estimation of precipitation rate. An algorithm was developed for estimating instantaneous precipitation rate for the Advanced Microwave Sounding Unit (AMSU) ...

Chen, Frederick Wey-Min, 1975-

2004-01-01T23:59:59.000Z

275

Processing and Performance of Materials using Microwaves, Electric ...  

Science Conference Proceedings (OSTI)

Symposium, Rustum Roy Memorial Symposium: Processing and Performance of Materials using Microwaves, Electric and Magnetic Fields, Ultrasound, Lasers, ...

276

Microwave Effect on Densification Kinetics during the Sintering of ...  

Science Conference Proceedings (OSTI)

Symposium, Rustum Roy Memorial Symposium: Processing and Performance of Materials using Microwaves, Electric and Magnetic Fields, Ultrasound, Lasers, ...

277

A Novel Microwave Assisted Phosphate Coating Process for ...  

Science Conference Proceedings (OSTI)

Microstructural Characteristics of Nano Calcium Phosphates Doped with Fluoride and Titanium Ions · Microwave Assisted Synthesis of Nano Hydroxyapatite ...

278

Microwave Brazing of Gas Turbine Components - Programmaster.org  

Science Conference Proceedings (OSTI)

Presentation Title, Microwave Brazing of Gas Turbine Components ... A Breakthrough Application of Electricity at High Temperature for Steel Production: Molten ...

279

An Explanation of Microwave Effects by Expansion of Transit State ...  

Science Conference Proceedings (OSTI)

... State Theories with Disturbed Velocity Distributions by Microwave. Author(s), Motoyasu Sato, Jun Fukushima, kyouichiro Kashimura, Sadatugu Takayama.

280

Mechanism of Microwave Heating of Dielectric and Magnetic  

Science Conference Proceedings (OSTI)

New Saccharification Process of Cellulosic Biomass by Microwave Irradiation · Novel Lamination Method for Large Armor Panels · Raman Spectroscopy for ...

Note: This page contains sample records for the topic "microwave background cmb" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Reduction Behavior of TiO 2 during Microwave Heating  

Science Conference Proceedings (OSTI)

New Saccharification Process of Cellulosic Biomass by Microwave Irradiation · Novel Lamination Method for Large Armor Panels · Raman Spectroscopy for ...

282

Microwave Heating Of Copper Powders in a Single Mode Cavity  

Science Conference Proceedings (OSTI)

New Saccharification Process of Cellulosic Biomass by Microwave Irradiation · Novel Lamination Method for Large Armor Panels · Raman Spectroscopy for ...

283

The Effect of Temperature on Dielectric Permitivity and Microwave ...  

Science Conference Proceedings (OSTI)

Dielectric property and microwave absorption property of anthracite were measured ... Effect of Continuous Cooling Rate on Microstructural Transformation of ...

284

Microwave off-gas treatment apparatus and process  

DOE Patents (OSTI)

The invention discloses a microwave off-gas system in which microwave energy is used to treat gaseous waste. A treatment chamber is used to remediate off-gases from an emission source by passing the off-gases through a susceptor matrix, the matrix being exposed to microwave radiation. The microwave radiation and elevated temperatures within the combustion chamber provide for significant reductions in the qualitative and quantitative emissions of the gas waste stream.

Schulz, Rebecca L. (Aiken, SC); Clark, David E. (Gainesville, FL); Wicks, George G. (North Aiken, SC)

2003-01-01T23:59:59.000Z

285

Microwave accelerator E-beam pumped laser  

DOE Patents (OSTI)

A device and method for pumping gaseous lasers by means of a microwave accelerator. The microwave accelerator produces a relativistic electron beam which is applied along the longitudinal axis of the laser through an electron beam window. The incident points of the electron beam on the electron beam window are varied by deflection coils to enhance the cooling characteristics of the foil. A thyratron is used to reliably modulate the microwave accelerator to produce electron beam pulses which excite the laser medium to produce laser pulse repetition frequencies not previously obtainable. An aerodynamic window is also disclosed which eliminates foil heating problems, as well as a magnetic bottle for reducing laser cavity length and pressures while maintaining efficient energy deposition.

Brau, Charles A. (Los Alamos, NM); Stein, William E. (Los Alamos, NM); Rockwood, Stephen D. (Los Alamos, NM)

1980-01-01T23:59:59.000Z

286

Open Ended Microwave Oven for Packaging  

E-Print Network (OSTI)

A novel open waveguide cavity resonator is presented for the combined variable frequency microwave curing of bumps, underfills and encapsulants, as well as the alignment of devices for fast flip-chip assembly, direct chip attach (DCA) or wafer-scale level packaging (WSLP). This technology achieves radio frequency (RF) curing of adhesives used in microelectronics, optoelectronics and medical devices with potential simultaneous micron-scale alignment accuracy and bonding of devices. In principle, the open oven cavity can be fitted directly onto a flip-chip or wafer scale bonder and, as such, will allow for the bonding of devices through localised heating thus reducing the risk to thermally sensitive devices. Variable frequency microwave (VFM) heating and curing of an idealised polymer load is numerically simulated using a multi-physics approach. Electro-magnetic fields within a novel open ended microwave oven developed for use in micro-electronics manufacturing applications are solved using a de icated Yee sche...

Sinclair, K I; Desmulliez, M Y P; Goussetis, G; Bailey, C; Parrott, K; Sangster, A J

2008-01-01T23:59:59.000Z

287

Apparatus for microwave heat treatment of manufactured components  

DOE Patents (OSTI)

An apparatus for heat treating manufactured components using microwave energy and microwave susceptor material. Heat treating medium such as eutectic salts may be employed. A fluidized bed introduces process gases which may include carburizing or nitriding gases. The process may be operated in a batch mode or continuous process mode. A microwave heating probe may be used to restart a frozen eutectic salt bath.

Babcock & Wilcox Technical Services Y-12, LLC (Oak Ridge, TN)

2008-04-15T23:59:59.000Z

288

Methods for microwave heat treatment of manufactured components  

DOE Patents (OSTI)

An apparatus for heat treating manufactured components using microwave energy and microwave susceptor material. Heat treating medium such as eutectic salts may be employed. A fluidized bed introduces process gases which may include carburizing or nitriding gases. The process may be operated in a batch mode or continuous process mode. A microwave heating probe may be used to restart a frozen eutectic salt bath.

Ripley, Edward B. (Knoxville, TN)

2010-08-03T23:59:59.000Z

289

TEC Working Group Background | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Background Background TEC Working Group Background Through the TEC/WG, DOE interacted with representatives of organizations at the state, tribal, and local levels to obtain input for program needs assessment, development and management, and to enhance their capability to carry out transportation emergency preparedness and safety activities specifically related to radioactive materials shipments. TEC membership included representatives from national, state, tribal and local government organizations, labor, industry and professional groups. Members meet semiannually to participate in plenary sessions, breakout work sessions, and in more specialized Topic Groups. To learn more about the history and background of TEC, please see the following documents: TEC Charter TEC Work Plan

290

TEC Working Group Background | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

TEC Working Group Background TEC Working Group Background TEC Working Group Background Through the TEC/WG, DOE interacted with representatives of organizations at the state, tribal, and local levels to obtain input for program needs assessment, development and management, and to enhance their capability to carry out transportation emergency preparedness and safety activities specifically related to radioactive materials shipments. TEC membership included representatives from national, state, tribal and local government organizations, labor, industry and professional groups. Members meet semiannually to participate in plenary sessions, breakout work sessions, and in more specialized Topic Groups. To learn more about the history and background of TEC, please see the following documents:

291

Background Links | National Nuclear Security Administration  

National Nuclear Security Administration (NNSA)

Background Links Home > About Us > Our Programs > Defense Programs > Future Science & Technology Programs > Office of Advanced Simulation and Computing Institutional Research...

292

4.6.1.1. Background & Data  

Science Conference Proceedings (OSTI)

4. Process Modeling 4.6. Case Studies in Process Modeling 4.6.1. Load Cell Calibration 4.6.1.1. Background & Data. Description ...

2013-10-30T23:59:59.000Z

293

Second National Climate Assessment: Background and Process  

NLE Websites -- All DOE Office Websites (Extended Search)

information on the background and process materials that were used to produce the report: An Agenda for Climate Science Impacts Primary Sources of Information Data Sets References...

294

‹ Countries Russia Background - Energy Information Administration  

U.S. Energy Information Administration (EIA)

‹ Countries Russia Last Updated: September 18, 2012 full report Background Russia holds the world's largest natural gas reserves, the second-largest coal reserves, and

295

Ground-Based Microwave Radiometer Measurements  

NLE Websites -- All DOE Office Websites (Extended Search)

Ground-Based Microwave Radiometer Measurements Ground-Based Microwave Radiometer Measurements and Radiosonde Comparisons During the WVIOP2000 Field Experiment D. Cimini University of L'Aquila L'Aquil, Italy E. R. Westwater Cooperative Institute for Research in the Environmental Sciences University of Colorado National Oceanic and Atmospheric Administration Environmental Technology Laboratory Boulder, Colorado Y. Han Science System Applications National Aeronautics Space Administration Goddard Space Flight Center Greenbelt, Maryland S. Keihm Jet Propulsion Laboratory California Institute of Technology Pasadena, California Introduction During September to October 2000, a water vapor intensive operational period (WVIOP) was conducted at the Atmospheric Radiation Measurement (ARM) Program's Southern Great Plains (SGP) Cloud and

296

Numerical and experimental modelling of microwave applicators  

E-Print Network (OSTI)

area of use is for the processing of food, the tempering of fruit, meat, fish and dairy produce, for the heating and cooking of meals and for sterilisation and pasteurisation. The domestic microwave oven is now a common household appliance throughout... the world and many food producers are turning to microwave heating as a means of achieving the high quality products demanded by todays consumers. The sizes of these systems can range from a few hundred watts for a domestic oven to over 250 kilowatts for a...

Dibben, David

1995-10-24T23:59:59.000Z

297

Synthesis of ultrafine powders by microwave heating  

DOE Patents (OSTI)

A method of synthesizing ultrafine powders using microwaves is described. A water soluble material is dissolved in water and the resulting aqueous solution is exposed to microwaves until the water has dissolved. The resulting material is an ultrafine powder. This method can be used to make Al/sub 2/O/sub 3/, NiO /plus/ Al/sub 2/O/sub 3/ and NiO as well as a number of other materials including GaBa/sub 2/Cu/sub 3/O/sub x/. 1 tab.

Meek, T.T.; Sheinberg, H.; Blake, R.D.

1987-04-24T23:59:59.000Z

298

Hanford Site background: Part 1, Soil background for nonradioactive analytes. Revision 1, Volume 2  

Science Conference Proceedings (OSTI)

Volume two contains the following appendices: Description of soil sampling sites; sampling narrative; raw data soil background; background data analysis; sitewide background soil sampling plan; and use of soil background data for the detection of contamination at waste management unit on the Hanford Site.

Not Available

1993-04-01T23:59:59.000Z

299

Recent experience with backgrounds at the SLC  

SciTech Connect

During the 1990 SLC/Mark II runs, machine backgrounds visible in the new vertex detectors were studied. These detectors had active elements at radii from 3 to 17 cm and were subjected to backgrounds unique to linear colliders. We describe recent progress in identifying sources and developing control techniques. 4 refs., 3 figs.

Jacobsen, R.; Band, H.; Barklow, T.; Bazarko, A.; Brown, K.; Burke, D.; Coupal, D.; DeStaebler, H.; Fujino, D.; Hearty, C.; Hertzbach, S.; Jaros, J.; Maruyama, T.; Tauchi, T.; Toge, N.; Turk, J.; Wagner, S.; Zeitlin, C.

1991-05-01T23:59:59.000Z

300

Optimized ECR plasma apparatus with varied microwave window thickness  

DOE Patents (OSTI)

The present invention describes a technique to control the radial profile of microwave power in an ECR plasma discharge. In order to provide for a uniform plasma density to a specimen, uniform energy absorption by the plasma is desired. By controlling the radial profile of the microwave power transmitted through the microwave window of a reactor, the profile of the transmitted energy to the plasma can be controlled in order to have uniform energy absorption by the plasma. An advantage of controlling the profile using the window transmission characteristics is that variations to the radial profile of microwave power can be made without changing the microwave coupler or reactor design. 9 figs.

Berry, L.A.

1995-11-14T23:59:59.000Z

Note: This page contains sample records for the topic "microwave background cmb" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Optimized ECR plasma apparatus with varied microwave window thickness  

DOE Patents (OSTI)

The present invention describes a technique to control the radial profile of microwave power in an ECR plasma discharge. In order to provide for a uniform plasma density to a specimen, uniform energy absorption by the plasma is desired. By controlling the radial profile of the microwave power transmitted through the microwave window of a reactor, the profile of the transmitted energy to the plasma can be controlled in order to have uniform energy absorption by the plasma. An advantage of controlling the profile using the window transmission characteristics is that variations to the radial profile of microwave power can be made without changing the microwave coupler or reactor design.

Berry, Lee A. (Oak Ridge, TN)

1995-01-01T23:59:59.000Z

302

History of the Pulsed Power, Beams, and Microwaves Laboratory The Directed Energy Microwave Laboratory is a 4100 square foot facility located in  

E-Print Network (OSTI)

History of the Pulsed Power, Beams, and Microwaves Laboratory The Directed Energy Microwave of the Directed Energy Microwave Laboratory is to: · educate MS and PhD scientists and engineers

Sen, Pradeep

303

Microwave instabilities in Booster and AGS  

SciTech Connect

Microwave instabilities is evaluated for the Booster and AGS for the preparation of the relativistic heavy ion collider. We found that the Booster may require feedback system for the transverse instability at the high intensity proton operation. The coherent instability is not important for the nominal RhIC operational intensity.

Lee, S.Y.; Zhao, X.F.

1987-03-13T23:59:59.000Z

304

Environmental assessment: South microwave communication facilities  

SciTech Connect

Western Area Power Administration (Western) is proposing to construct, operate, and maintain eight microwave repeater stations in southwestern Colorado, southeastern Utah, and northern Arizona, in order to meet the minimum fade criteria established by the Western Systems Coordinating Council (WSCC) for the operation and protection of electric power systems. The proposed microwave facilities would increase the reliability of communication. This environmental assessment (EA) describes the existing environmental conditions and the impacts from construction of the eight microwave communication facilities. The EA was prepared in compliance with the National Environmental Policy Act of 1969, the Council on Environmental Quality Regulations (40 CFR 1500-1508), and the Department of Energy Guidelines (52 FR 47662, December 15, 1987). The proposed project would consist of constructing eight microwave facilities, each of which would include a self-supported lattice tower, an equipment building, a propane tank, distribution lines to provide electric power to the sites, and access roads to the sites. The facilities would be constructed in San Miguel and Montezuma Counties in Colorado, San Juan County, Utah, and Navajo, Apache, Coconino, and Yavapai Counties in Arizona. 20 refs., 2 figs., 2 tabs.

Not Available

1989-06-01T23:59:59.000Z

305

Interaction of high power microwave with plasma  

Science Conference Proceedings (OSTI)

An experimental proposal to investigate the physics of interaction of extremely intense (eEem/m?c ? 1) microwave in an overdense plasma is discussed. The output from a VIRCATOR (2 -- 10 GHz, ? 1 -- 3 GW) based pulse (?30 ns) powered ...

V. P. Anitha; Amita Das; Y. C. Saxena; Anurag Shyam; P. K. Kaw

2011-02-01T23:59:59.000Z

306

Effects of Microwave Radiation on Oil Recovery  

Science Conference Proceedings (OSTI)

A variety of oil recovery methods have been developed and applied to mature and depleted reservoirs in order to improve the efficiency. Microwave radiation oil recovery method is a relatively new method and has been of great interest in the recent years. Crude oil is typically co?mingled with suspended solids and water. To increase oil recovery

2011-01-01T23:59:59.000Z

307

Profiling Atmospheric Water Vapor by Microwave Radiometry  

Science Conference Proceedings (OSTI)

High-altitude microwave radiometric observations at frequencies near 92 and 183.3 GHz were used to study the potential of retrieving atmospheric water vapor profiles over both land and water. An algorithm based on an extended Kaiman-Bucy filter ...

J. R. Wang; J. L. King; T. T. Wilheit; G. Szejwach; L. H. Gesell; R. A. Nieman; D. S. Niver; B. M. Krupp; J. A. Gagliano

1983-05-01T23:59:59.000Z

308

Planar controlled zone microwave plasma system  

DOE Patents (OSTI)

An apparatus and method for initiating a process gas plasma. A conductive plate having a plurality of conductive fingers is positioned in a microwave applicator. An arc forms between the conductive fingers to initiate the formation of a plasma. A transport mechanism may convey process materials through the plasma. A spray port may be provided to expel processed materials.

Ripley, Edward B. (Knoxville, TN); Seals, Roland D. (Oak Ridge, TN); Morrell, Jonathan S. (Knoxvlle, TN)

2011-10-04T23:59:59.000Z

309

A SEARCH FOR CONCENTRIC CIRCLES IN THE 7 YEAR WILKINSON MICROWAVE ANISOTROPY PROBE TEMPERATURE SKY MAPS  

SciTech Connect

In this Letter, we search for concentric circles with low variance in cosmic microwave background sky maps. The detection of such circles would hint at new physics beyond the current cosmological concordance model, which states that the universe is isotropic and homogeneous, and filled with Gaussian fluctuations. We first describe a set of methods designed to detect such circles, based on matched filters and {chi}{sup 2} statistics, and then apply these methods to the best current publicly available data, the 7 year Wilkinson Microwave Anisotropy Probe (WMAP) temperature sky maps. We compare the observations with an ensemble of 1000 Gaussian {Lambda}CDM simulations. Based on these tests, we conclude that the WMAP sky maps are fully compatible with the Gaussian and isotropic hypothesis as measured by low-variance ring statistics.

Wehus, I. K. [Department of Physics, University of Oslo, P.O. Box 1048 Blindern, N-0316 Oslo (Norway); Eriksen, H. K., E-mail: i.k.wehus@fys.uio.no [Institute of Theoretical Astrophysics, University of Oslo, P.O. Box 1029 Blindern, N-0315 Oslo (Norway)

2011-06-01T23:59:59.000Z

310

Gauss-Bonnet Quintessence: Background Evolution, Large Scale Structure and Cosmological Constraints  

E-Print Network (OSTI)

We investigate a string-inspired dark energy scenario featuring a scalar field with a coupling to the Gauss-Bonnet invariant. Such coupling can trigger the onset of late dark energy domination after a scaling matter era. The universe may then cross the phantom divide and perhaps also exit from the acceleration. We discuss extensively the cosmological and astrophysical implications of the coupled scalar field. Data from the Solar system, supernovae Ia, cosmic microwave background radiation, large scale structure and big bang nucleosynthesis is used to constrain the parameters of the model. A good Newtonian limit may require to fix the coupling. With all the data combined, there appears to be some tension with the nucleosynthesis bound, and the baryon oscillation scale seems to strongly disfavor the model. These possible problems might be overcome in more elaborate models. In addition, the validity of these constraints in the present context is not strictly established. Evolution of fluctuations in the scalar field and their impact to clustering of matter is studied in detail and more model-independently. Small scale limit is derived for the perturbations and their stability is addressed. A divergence is found and discussed. The general equations for scalar perturbations are also presented and solved numerically, confirming that the Gauss-Bonnet coupling can be compatible with the observed spectrum of cosmic microwave background radiation as well as the matter power spectrum inferred from large scale surveys.

Tomi Koivisto; David F. Mota

2006-09-22T23:59:59.000Z

311

MADCAP The Microwave Anisotropy Dataset Computational Analysis Package  

E-Print Network (OSTI)

Realizing the extraordinary scientific potential of the CMB requires precise measurements of its tiny anisotropies over a significant fraction of the sky at very high resolution. The analysis of the resulting datasets is a serious computational challenge. Existing algorithms require terabytes of memory and hundreds of years of CPU time. We must therefore both maximize our resources by moving to supercomputers and minimize our requirements by algorithmic development. Here we will outline the nature of the challenge, present our current optimal algorithm, and discuss its implementation as the MADCAP software package and application to data from the North American test flight of the joint Italian-U.S. BOOMERanG experiment on the Cray T3E at NERSC and CINECA. A documented beta-release of MADCAP is publicly available at http://cfpa.berkeley.edu/~borrill/cmb/madcap.html

Borrill, J

1999-01-01T23:59:59.000Z

312

MADCAP - The Microwave Anisotropy Dataset Computational Analysis Package  

E-Print Network (OSTI)

Realizing the extraordinary scientific potential of the CMB requires precise measurements of its tiny anisotropies over a significant fraction of the sky at very high resolution. The analysis of the resulting datasets is a serious computational challenge. Existing algorithms require terabytes of memory and hundreds of years of CPU time. We must therefore both maximize our resources by moving to supercomputers and minimize our requirements by algorithmic development. Here we will outline the nature of the challenge, present our current optimal algorithm, and discuss its implementation as the MADCAP software package and application to data from the North American test flight of the joint Italian-U.S. BOOMERanG experiment on the Cray T3E at NERSC and CINECA. A documented beta-release of MADCAP is publicly available at http://cfpa.berkeley.edu/~borrill/cmb/madcap.html

Julian Borrill

1999-11-19T23:59:59.000Z

313

Charged Hadron Properties in Background Electric Fields  

E-Print Network (OSTI)

We report on a lattice calculation demonstrating a novel new method to extract the electric polarizability of charged pseudo-scalar mesons by analyzing two point correlation functions computed in classical background electric fields.

William Detmold; Brian C. Tiburzi; Andre Walker-Loud

2009-10-27T23:59:59.000Z

314

First National Climate Assessment: Background and Process  

NLE Websites -- All DOE Office Websites (Extended Search)

Background and Process Print E-mail Workshops of the First National Climate Assessment In February 1997, the U.S. Global Change Research Program and the Office of Science and...

315

Charged Hadron Properties in Background Electric Fields  

SciTech Connect

We report on a lattice calculation demonstrating a novel new method to extract the electric polarizability of charged pseudo-scalar mesons by analyzing two point correlation functions computed in classical background electric fields.

William Detmold, Brian C. Tiburzi, Andre Walker-Loud

2010-02-01T23:59:59.000Z

316

Microsoft Word - Appendix A_Background.doc  

Office of Legacy Management (LM)

Background Information, Remedial Action Histories, Background Information, Remedial Action Histories, Present Site Conditions U.S. Department of Energy Weldon Spring Site LTS&M Plan July 2005 Doc. No. S0079000 Page A-iii Contents A1.1 Location and Property Ownership ................................................................................1 A1.2 Physiography and Topography.....................................................................................4 A1.3 Hydrogeology ...............................................................................................................5 A1.3.1 Regional ...........................................................................................................5 A1.3.2 Chemical Plant .................................................................................................5

317

Literature Review of Background Polycyclic Aromatic Hydrocarbons  

Science Conference Proceedings (OSTI)

Polycyclic aromatic hydrocarbons (PAHs) continuously move through the environment, often via atmospheric transport. The subsequent deposition of particulates containing PAHs along with other sources of PAHs, such as natural vegetative decay, result in "background" PAHs in surficial soils. Even in pristine areas, surface and near surface soils can contain detectable levels of PAHs. This study provides data on the concentrations and distributions of background PAHs observed in environmental media. Such inf...

2000-03-20T23:59:59.000Z

318

COBE Observations of the Cosmic Infrared Background  

E-Print Network (OSTI)

The Diffuse InfraRed Background Experiment on COBE measured the total infrared signal seen from space at a distance of 1 astronomical unit from the Sun. Using time variations as the Earth orbits the Sun, it is possible to remove most of the foreground signal produced by the interplanetary dust cloud [zodiacal light]. By correlating the DIRBE signal with the column density of atomic hydrogen measured using the 21 cm line, it is possible to remove most of the foreground signal produced by interstellar dust, although one must still be concerned by dust associated with H_2 (molecular gas) and H II (the warm ionized medium). DIRBE was not able to determine the CIRB in the 5-60 micron wavelength range, but did detect both a far infrared background and a near infrared background. The far infrared background has an integrated intensity of about 34 nW/m^2/sr, while the near infrared and optical extragalactic background has about 59 nW/m^2/sr. The Far InfraRed Absolute Spectrophotometer (FIRAS) on COBE has been used to constrain the long wavelength tail of the far infrared background but a wide range of intensities at 850 microns are compatible with the FIRAS data. Thus the fraction of the CIRB produced by SCUBA sources has large uncertainties in both the numerator and the denominator.

E. L. Wright

2003-06-03T23:59:59.000Z

319

Apparatus and method for microwave processing of materials  

DOE Patents (OSTI)

Disclosed is a variable frequency microwave heating apparatus designed to allow modulation of the frequency of the microwaves introduced into a furnace cavity for testing or other selected applications. The variable frequency heating apparatus is used in the method of the present invention to monitor the resonant processing frequency within the furnace cavity depending upon the material, including the state thereof, from which the workpiece is fabricated. The variable frequency microwave heating apparatus includes a microwave signal generator and a high-power microwave amplifier or a microwave voltage-controlled oscillator. A power supply is provided for operation of the high-power microwave oscillator or microwave amplifier. A directional coupler is provided for detecting the direction and amplitude of signals incident upon and reflected from the microwave cavity. A first power meter is provided for measuring the power delivered to the microwave furnace. A second power meter detects the magnitude of reflected power. Reflected power is dissipated in the reflected power load. 10 figs.

Johnson, A.C.; Lauf, R.J.; Bible, D.W.; Markunas, R.J.

1996-05-28T23:59:59.000Z

320

The South Pole Telescope bolometer array and the measurement of secondary Cosmic Microwave Background anisotropy at small angular scales  

E-Print Network (OSTI)

poorly coupled excess heat capacity; this extended modelbolometer. The TES, with heat capacity C TES is connectedlumped thermal element with heat capacity C 0 and electrical

Shirokoff, Erik D.

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "microwave background cmb" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

National Climate Assessment: Background and Process  

NLE Websites -- All DOE Office Websites (Extended Search)

Background and Process Print E-mail Background and Process Print E-mail Please view the links below to find out more about the background and process of the National Climate Assessment: National Climate Assessment Development & Advisory Committee Charter ( PDF) National Climate Assessment Proposed 2013 Report Outline [updated on 12/08/2011] (PDF) Strategy On May 20th, 2011 the National Climate Assessment released the following two strategy documents: National Climate Assessment Strategy Summary National Climate Assessment Engagement Strategy Federal Register Notices November 18, 2013 National Climate Assessment and Development Advisory Committee (NCADAC) Notice of Open Meeting pdf | html A Notice by the National Oceanic and Atmospheric Administration on 10/29/2013 This notice sets forth the schedule of a forthcoming meeting of the DoC NOAA National Climate Assessment and Development Advisory Committee (NCADAC).

322

Monitored Retrievable Storage Background | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Monitored Retrievable Storage Background Monitored Retrievable Storage Background Monitored Retrievable Storage Background `The U.S. Government is seeking a site for a monitored retrievable storage facility (MRS). Employing proven technologies used in this country and abroad, the MRS will be an Integral part of the Federal system for safe and permanent disposal of the nation's high-level radioactive wastes. The MRS will accept shipments of spent fuel from commercial nuclear power plants, temporarily store the spent fuel above ground, and stage shipments of it to a geologic repository for permanent disposal. The law authorizing the MRS provides an opportunity for a State or an Indian Tribe to volunteer to host the MRS. The law establishes the Office of the Nuclear Waste Negotiator, who Is 10 seek a State or an Indian Tribe

323

DOE Hydrogen and Fuel Cells Program: Background  

NLE Websites -- All DOE Office Websites (Extended Search)

Mission and Goals Mission and Goals Organization Chart and Contacts Background U.S. DRIVE Partnership Budget Timeline Program Activities Advisory Panels External Coordination U.S. Department of Energy Search help Home > About > Background Printable Version Background In the early 1970s, concern over our growing dependence on imported petroleum, coupled with concerns about our deteriorating air quality due to emissions from combustion of fossil fuels, spurred the Federal government to act. The timeline below provides policy and programmatic highlights for federally supported hydrogen and fuel cell R&D over the last three decades. Federal Support for Hydrogen and Fuel Cell R&D Some of the following documents are available as Adobe Acrobat PDFs. Download Adobe Reader.

324

Background compensation for a radiation level monitor  

DOE Patents (OSTI)

Background compensation in a device such as a hand and foot monitor is provided by digital means using a scaler. With no radiation level test initiated, a scaler is down-counted from zero according to the background measured. With a radiation level test initiated, the scaler is up-counted from the previous down-count position according to the radiation emitted from the monitored object and an alarm is generated if, with the scaler having crossed zero in the positive going direction, a particular number is exceeded in a specific time period after initiation of the test. If the test is initiated while the scale is down-counting, the background count from the previous down- count stored in a memory is used as the initial starting point for the up-count.

Keefe, D.J.

1975-12-01T23:59:59.000Z

325

Ground-based Microwave Cloud Tomography  

NLE Websites -- All DOE Office Websites (Extended Search)

Microwave Cloud Tomography Microwave Cloud Tomography Experiment, SGP, May 15-June 15, 2009 Lead Scientist Dong Huang, BNL Co-Investigators Al Gasiewski, UC Boulder Maria Cadeddu, ANL Warren Wiscombe, BNL Radiation Processes Working Group March 30, 2009 multiple radiometers All good cloud radiation modelers should close their airplane window shades so as not to be corrupted by the spectacle of real 3D clouds. - Roger Davies In case you forget to do this, you see 3/30/2009 ARM RPWG 2 Effects of cloud structure on radiation 3/30/2009 ARM RPWG 3 Typical climate model - Cloud fraction & mean water content - Horizontally uniform clouds, no side radiation - Assumption on overlap Courtesy of Bernhard Mayer Cloud structure important to radiation - Cumulus (Benner & Evans 2001, Pincus et al. 2005), deep convection (DiGiuseppe &

326

Strange Metallic Behavior in Anisotropic Background  

E-Print Network (OSTI)

We continue our analysis on conductivity in the anisotropic background by employing the D-brane probe technique, where the D-branes play the role of charge carriers. The DC and AC conductivity for massless charge carriers are obtained analytically, while interesting curves for the AC conductivity are also plotted. For massive charge carriers, we calculate the DC and AC conductivities in the dilute limit and we fix the parameters in the Einstein-Maxwell-dilaton theory so that the background exhibits the same scaling behaviors as those for real-world strange metals. The DC conductivity at finite density is also computed.

Lee, Bum-Hoon; Park, Chanyong

2010-01-01T23:59:59.000Z

327

Strange Metallic Behavior in Anisotropic Background  

E-Print Network (OSTI)

We continue our analysis on conductivity in the anisotropic background by employing the D-brane probe technique, where the D-branes play the role of charge carriers. The DC and AC conductivity for massless charge carriers are obtained analytically, while interesting curves for the AC conductivity are also plotted. For massive charge carriers, we calculate the DC and AC conductivities in the dilute limit and we fix the parameters in the Einstein-Maxwell-dilaton theory so that the background exhibits the same scaling behaviors as those for real-world strange metals. The DC conductivity at finite density is also computed.

Bum-Hoon Lee; Da-Wei Pang; Chanyong Park

2010-06-09T23:59:59.000Z

328

LRL background measurements program for ICBM discrimination  

SciTech Connect

Several proposals have been made for discriminating between Intercontinental Ballistic Missiles (ICBM) and decoys. Primary fundamental particles or high energy electromagnetic radiation can be scattered from or can activate the targets. The secondary radiation is observed by directional detectors that are positioned close-by and the information is transmitted to control centers on the ground. Lawrence Livermore Laboratory proposes a program for measurements of the natural space radiations. Eventually, the space backgrounds must be measured before a satisfactory discrimination system can be perfected. Past and scheduled background measurements are described and a measurement program is proposed.

1960-03-09T23:59:59.000Z

329

A container for heat treating materials in microwave ovens  

DOE Patents (OSTI)

The efficiency of a microwave oven of a conventional two-source configuration and energy level is increased by providing the oven with a container for housing a refractory material to be treated. The container is formed to top and bottom walls transparent to microwaves while the sidewalls, in a circular configuration, are formed of a nonmetallic material opaque to microwave radiation for reflecting the radiation penetrating the top and bottom walls radially inwardly into the center of the container wherein a casket of heat-insulating material is provided for housing the material to be heat treated. The reflection of the microwave radiation from the sidewalls increases the concentration of the microwaves upon the material being heat treated while the concentration of the microwaves upon the material being heat treated while the casket retains the heat to permit the heating of the material to a substantially higher temperature than achievable in the oven without the container.

Holcombe, C.E.; Dykes, N.L.; Kimrey, H.D. Jr.; Mills, J.E.

1988-01-26T23:59:59.000Z

330

Applications for Microwave Generators in the Process Industries  

E-Print Network (OSTI)

Microwaves find widespread use in radar applications, in telephonic communications, and in the generation of thermal energy for heating. It is this last use that is of interest here. The use of microwave generators to dry heat-sensitive materials and regenerate beds of solid adsorbents is currently being investigated at The University of Texas. This paper summarizes the first phase of this program, which involves microwave drying of various types of polymers. Future research goals and programs are also presented.

Humphrey, J. L.; Vasilakos, N. P.

1983-01-01T23:59:59.000Z

331

Survey Background and Technical Information on CBECS  

U.S. Energy Information Administration (EIA) Indexed Site

Survey Background and Technical Information Survey Background and Technical Information Survey Background and Technical Information Survey Background The commercial sector encompasses a vast range of building types- service businesses, such as retail and wholesale stores, hotels and motels, restaurants, and hospitals, as well as certain buildings that would not be considered "commercial" in a traditional economic sense, such as public and private schools, correctional institutions, and religious and fraternal organizations. Excluded from the sector are the goods-producing industries: manufacturing, agriculture, mining, forestry and fisheries, and construction. Nearly all energy use in the commercial sector takes place in, or is associated with, the buildings that house these commercial activities. Analysis of the structures, activities, and equipment associated with different types of buildings is the clearest way to evaluate commercial sector energy use. The Commercial Buildings Energy Consumption Survey (CBECS) is a national-level sample survey of commercial buildings and their energy suppliers conducted quadrennially (previously triennially) by the Energy Information Administration (EIA). The 2003 CBECS was the eighth survey in the series begun in 1979. From 1979 to 1986, the survey was known as the Nonresidential Buildings Energy Consumption Survey, or NBECS.

332

Yale ME Turbine Test cell instructions Background  

E-Print Network (OSTI)

Yale ME Turbine Test cell instructions Background: The Turbine Technologies Turbojet engine combustion gas backflow into the lab space. Test Cell preparation: 1. Turn on Circuit breakers # 16 of the turbine and check a few items: o Open keyed access door on rear of Turbine enclosure o Check Jet A fuel

Haller, Gary L.

333

Variational Assimilation of Global Microwave Rainfall Retrievals: Physical and Dynamical Impact on GEOS Analyses  

Science Conference Proceedings (OSTI)

Global microwave rainfall retrievals from a five-satellite constellation, including the Tropical Rainfall Measuring Mission Microwave Imager, Special Sensor Microwave Imager from the Defense Meteorological Satellite Program F13, F14, and F15, and ...

Xin Lin; Sara Q. Zhang; Arthur Y. Hou

2007-08-01T23:59:59.000Z

334

Spatial Variability of Summer Florida Precipitation and Its Impact on Microwave Radiometer Rainfall-Measurement Systems  

Science Conference Proceedings (OSTI)

Three-dimensional radar data for three summer Florida storm are used as input to a microwave radiative transfer model. The model simulates microwave brightness observations by a 19-GHz, nadir-pointing, satellite-borne microwave radiometer.

B. J. Turner; G. L. Austin

1993-02-01T23:59:59.000Z

335

Rainfall Estimation over Oceans from SMMR and SSM/I Microwave Data  

Science Conference Proceedings (OSTI)

Passive microwave measurements made by the Scanning Multichannel Microwave Radiometer (SMMR) and the Special Sensor Microwave/Imager (SSM/I) reveal information about rain and precipitation-sized ice in the field of view (FOV) of the instruments. ...

C. Prabhakara; G. Dalu; G. L. Liberti; J. J. Nucciarone; R. Suhasini

1992-06-01T23:59:59.000Z

336

A prototype system for measuring microwave frequency reflections from the breast  

Science Conference Proceedings (OSTI)

Microwave imaging of the breast is of interest for monitoring breast health, and approaches to active microwave imaging include tomography and radar-based methods. While the literature contains a growing body of work related to microwave breast imaging, ...

J. Bourqui; J. M. Sill; E. C. Fear

2012-01-01T23:59:59.000Z

337

Product Standards for Microwaves (Japan) | Open Energy Information  

Open Energy Info (EERE)

Product Standards for Microwaves (Japan) Product Standards for Microwaves (Japan) Jump to: navigation, search Tool Summary LAUNCH TOOL Name: Product Standards for Microwaves (Japan) Focus Area: Appliances & Equipment Topics: Policy Impacts Website: www.eccj.or.jp/top_runner/pdf/tr_microwaveoven.pdf Equivalent URI: cleanenergysolutions.org/content/product-standards-microwaves-japan Language: English Policies: "Deployment Programs,Regulations" is not in the list of possible values (Deployment Programs, Financial Incentives, Regulations) for this property. DeploymentPrograms: Industry Codes & Standards Regulations: Appliance & Equipment Standards and Required Labeling This Energy Conservation Center Japan (ECCJ) document was created as a guide in response to its newly established set of standards and labelling

338

Microwave Sintering of CaO Stabilized Nature Baddeleyite  

Science Conference Proceedings (OSTI)

Microwave sintering could fast heating and sintering. ... Characterization of Burrows from Mining District of Pachuca - Real Del Monte, in Hidalgo State and ...

339

Low Cost Processing: Plasma, Microwave, Laser, Melting and Casting  

Science Conference Proceedings (OSTI)

Mar 5, 2013 ... Cost Affordable Titanium IV: Low Cost Processing: Plasma, ... obtained by using microwave energy as the consolidation method of Mg-Ti alloys.

340

Microwave Assisted Synthesis of Nano Hydroxyapatite from Avian ...  

Science Conference Proceedings (OSTI)

Presentation Title, Microwave Assisted Synthesis of Nano Hydroxyapatite from Avian Eggshell Biowaste for Tissue Engineering. Author(s), Kajal K Mallick.

Note: This page contains sample records for the topic "microwave background cmb" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Micro Microwave Does Pinpoint Cooking for Miniaturized Labs  

Science Conference Proceedings (OSTI)

... Researchers at the National Institute of Standards and Technology (NIST) and ... Based on classical theory of how microwave energy is absorbed ...

2012-04-16T23:59:59.000Z

342

206 Preparation of Porous Mullite Composite by Microwave Sintering  

Science Conference Proceedings (OSTI)

During the microwave sintering, an insulation structure based on hybrid heating mode was well designed with the wall of mullite and the aided heaters of SiC ...

343

WIRELESS MICROWAVE ACOUSTIC SENSOR SYSTEM FOR CONDITION MONITORING...  

NLE Websites -- All DOE Office Websites (Extended Search)

WIRELESS MICROWAVE ACOUSTIC SENSOR SYSTEM FOR CONDITION MONITORING IN POWER PLANT ENVIRONMENTS Project DE-FE0007379TDD NETL, Morgantown, WV, March 14, 2012. DOE NETL Program:...

344

System to Continuously Produce Carbon Fiber via Microwave-Assisted ...  

ORNL 2011-G00246/jcn UT-B ID 200501518 09.2011 System to Continuously Produce Carbon Fiber via Microwave-Assisted Plasma Processing Technology Summary

345

Microwave Brazing, An Energy Efficient Method for Joining ...  

Science Conference Proceedings (OSTI)

However, microwave brazing methods for joining ceramics to metals, with the ... Air Brazing of Nicrofer-6025HT to BSCF for Oxygen Separation Membranes.

346

Simple microwave field imaging technique using hot atomic vapor cells  

E-Print Network (OSTI)

We demonstrate a simple technique for microwave field imaging using alkali atoms in a vapor cell. The microwave field to be measured drives Rabi oscillations on atomic hyperfine transitions, which are detected in a spatially resolved way using a laser beam and a CCD camera. Our vapor cell geometry enables single-shot recording of two-dimensional microwave field images with 350 {\\mu}m spatial resolution. Using microfabricated vapor cell arrays, a resolution of a few micrometers seems feasible. All vector components of the microwave magnetic field can be imaged. Our apparatus is simple and compact and does not require cryogenics or ultra-high vacuum.

Böhi, Pascal

2012-01-01T23:59:59.000Z

347

Simple microwave field imaging technique using hot atomic vapor cells  

E-Print Network (OSTI)

We demonstrate a simple technique for microwave field imaging using alkali atoms in a vapor cell. The microwave field to be measured drives Rabi oscillations on atomic hyperfine transitions, which are detected in a spatially resolved way using a laser beam and a camera. Our vapor cell geometry enables single-shot recording of two-dimensional microwave field images with 350 {\\mu}m spatial resolution. Using microfabricated vapor cell arrays, a resolution of a few micrometers seems feasible. All vector components of the microwave magnetic field can be imaged. Our apparatus is simple and compact and does not require cryogenics or ultra-high vacuum.

Pascal Böhi; Philipp Treutlein

2012-07-20T23:59:59.000Z

348

NIST Prototype 'Optics Table on a Chip' Places Microwave ...  

Science Conference Proceedings (OSTI)

... E. Zakka-Bajjani, F. Nguyen, M. Lee, LR Vale, RW Simmonds and J. Aumentado. Quantum superposition of a single microwave ...

2011-10-14T23:59:59.000Z

349

Understanding Non-thermal Microwave Effects in Materials Processing  

Science Conference Proceedings (OSTI)

Difference between Life and Death of Bacterium against Microwave Power under ... Sintering and Plastic Deformation of Ceramics under Pulsed Electric Current.

350

Exchange of Cs Ion in Clay Minerals by Microwave Application  

Science Conference Proceedings (OSTI)

Difference between Life and Death of Bacterium against Microwave Power under ... Sintering and Plastic Deformation of Ceramics under Pulsed Electric Current.

351

Dramatic Structuring of Water using Polarized Microwave and ...  

Science Conference Proceedings (OSTI)

Raman spectroscopy reveals that liquid water treated with 2.45 GHz polarized microwave and 13.56 MHz radiofrequency radiation undergoes dramatic ...

352

Determining Cloud Ice Water Path from High-Frequency Microwave...  

NLE Websites -- All DOE Office Websites (Extended Search)

Determining Cloud Ice Water Path from High-Frequency Microwave Measurements G. Liu Department of Meteorology Florida State University Tallahassee, Florida Introduction A better...

353

A Continuous Flow Microwave Reactor for Organic Synthesis.  

E-Print Network (OSTI)

??Microwave reactors are important tools in chemical synthesis, as they can lead to unprecedented reductions in reaction times and improved reaction yields. In order to… (more)

Sauks, Jennifer

2013-01-01T23:59:59.000Z

354

Session Papers Preliminary Analysis of Ground-Based Microwave...  

NLE Websites -- All DOE Office Websites (Extended Search)

Analysis of Ground-Based Microwave and Infrared Radiance Observations During the Pilot Radiation OBservation Experiment E. R. Westwater, Y. Han, J. H. Churnside, and J. B....

355

Posters Preliminary Analysis of Ground-Based Microwave and Infrared...  

NLE Websites -- All DOE Office Websites (Extended Search)

Analysis of Ground-Based Microwave and Infrared Radiance Observations During the Pilot Radiation OBservation Experiment E. R. Westwater, Y. Han, J. H. Churnside, and J. B....

356

Influence of Microwave Radiation on Phosphorus-removal Process ...  

Science Conference Proceedings (OSTI)

Microwave radiation on the ore fines was carried out using MW-HS ... A Pilot- plant Scale Test on DRI Preparation from High-alumina Limonite Ore by ...

357

MICROWAVE HEATING SIMULATION OF METALS AND DIELECTRIC CERAMICS.  

E-Print Network (OSTI)

??The research objectives proposed to study metal processing using a modular industrial microwave oven. The intent of the oven was to perform casting for metal… (more)

Warren, Brian C.

2013-01-01T23:59:59.000Z

358

System to continuously produce carbon fiber via microwave ...  

A system to continuously produce fully carbonized or graphitized carbon fibers using microwave-assisted plasma (MAP) processing comprises an elongated chamber in ...

359

Using Microwave Radiation for Removing Heavy Metal Ions and ...  

Science Conference Proceedings (OSTI)

Presentation Title, Using Microwave Radiation for Removing Heavy Metal Ions and Producing Biofuels. Author(s), Aharon Gedanken. On-Site Speaker (Planned ) ...

360

Synthesis of Divalent Sn Compounds under Microwave Non ...  

Science Conference Proceedings (OSTI)

Author(s), Hirotsugu Takizawa, Nozomi Sato, Jun Fukushima, Yamato Hayashi. On-Site Speaker (Planned), Hirotsugu Takizawa. Abstract Scope, Microwave ...

Note: This page contains sample records for the topic "microwave background cmb" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Microwave-assisted solvent extraction and gas chromatography ion ...  

Science Conference Proceedings (OSTI)

May 17, 2006 ... sistent organochlorine pesticides (POPs) in marine sedi- ment was ... variables microwave power, extraction time and tempera- ture, amount of ...

362

Investigation on a Microwave High-Temperature Air Heat Exchanger  

Science Conference Proceedings (OSTI)

In present paper, an energy efficient air heat exchanger, based on accumulation of the heat generated by microwave absorbing materials is presented according  ...

363

2300 °C Ultra-high Temperature Microwave Assist Technology ...  

Science Conference Proceedings (OSTI)

The design is based on a traditional graphite furnace with graphite insulation and heating elements. A microwave transition was specially designed to deliver the ...

364

Microwave heating for adsorbents regeneration and oil sands coke activation.  

E-Print Network (OSTI)

??Microwave heating has unique advantages compared to convection-radiation heating methods including fast heating rate and selective heating of objects. This thesis studied two applications of… (more)

Chen, Heng

2010-01-01T23:59:59.000Z

365

Continuous flow microwave heating : evaluation of system efficiency and enzyme inactivation kinetics.  

E-Print Network (OSTI)

??A continuous flow microwave heating system was set up by using one domestic microwave oven (1000W nominal output at 2450MHz). Water was run through the… (more)

Lin, Man Guang, 1966-

2004-01-01T23:59:59.000Z

366

First National Climate Assessment: Background and Process  

NLE Websites -- All DOE Office Websites (Extended Search)

Background and Process Print E-mail Background and Process Print E-mail Workshops of the First National Climate Assessment In February 1997, the U.S. Global Change Research Program and the Office of Science and Technology Policy initiated a series of Regional Climate Change Workshops with the goal of starting the process of examining the vulnerabilities of regions of the United States to climate variability and climate change. What was initially intended to be three or four workshops developed into a series of twenty, covering every state and territory of the United States. The workshops span from May 1997 to September 1998 and represented the first step in conducting a regional assessment. Each workshop was sponsored by one or more government agencies,and was carried out by coordinators from local institutions. For details on each workshop, including its geographic coverage, see:

367

Radioactive Background Evaluation by Atom Counting  

SciTech Connect

We propose a new method of measuring 85Kr background levels by direct counting of impurity atoms. The beta-decay of 85Kr is a significant radioactive background for experiments that use liquified noble gases to search for dark matter and measure the low-energy solar neutrino flux. While there are several proposed methods for reducing Kr levels in these experiments, an independent technique is needed for measuring very low Kr levels. By selectively exciting Kr atoms to a metastable state, capturing them in a magneto-optical trap (MOT), and detecting fluorescence from the trapped atoms, individual Kr atoms can be counted with a high signal-to-noise ratio. This approach offers both higher sensitivity and shorter measurement times than more conventional techniques, with an estimated sensitivity of 3 x 10-14 in only 3 hours of integration.

Orzel, Chad [Department of Physics and Astronomy, Union College, Schenectady, NY 12308 (United States); McKinsey, Daniel [Yale University, New Haven, CT 06511 (United States)

2005-09-08T23:59:59.000Z

368

Foreign Energy Company Competitiveness: Background information  

SciTech Connect

This report provides background information to the report Energy Company Competitiveness: Little to Do With Subsidies (DOE 1994). The main body of this publication consists of data uncovered during the course of research on this DOE report. This data pertains to major government energy policies in each country studied. This report also provides a summary of the DOE report. In October 1993, the Office of Energy Intelligence, US Department of Energy (formerly the Office of Foreign Intelligence), requested that Pacific Northwest Laboratory prepare a report addressing policies and actions used by foreign governments to enhance the competitiveness of their energy firms. Pacific Northwest Laboratory prepared the report Energy Company Competitiveness Little to Do With Subsidies (DOE 1994), which provided the analysis requested by DOE. An appendix was also prepared, which provided extensive background documentation to the analysis. Because of the length of the appendix, Pacific Northwest Laboratory decided to publish this information separately, as contained in this report.

Weimar, M.R.; Freund, K.A.; Roop, J.M.

1994-10-01T23:59:59.000Z

369

A background free double beta decay experiment  

E-Print Network (OSTI)

We present a new detection scheme for rejecting backgrounds in neutrino less double beta decay experiments. It relies on the detection of Cherenkov light emitted by electrons in the MeV region. The momentum threshold is tuned to reach a good discrimination between background and good events. We consider many detector concepts and a range of target materials. The most promising is a high-pressure 136Xe emitter for which the required energy threshold is easily adjusted. Combination of this concept and a high pressure Time Projection Chamber could provide an optimal solution. A simple and low cost effective solution is to use the Spherical Proportional Counter that provides two delayed signals from ionization and Cherenkov light. In solid-state double beta decay emitters, because of their higher density, the considered process is out of energy range. An alternative solution could be the development of double decay emitters with lower density by using for instance the aerogel technique. It is surprising that a technology used for particle identification in high-energy physics becomes a powerful tool for rejecting backgrounds in such low-energy experiments.

Ioannis Giomataris

2010-12-20T23:59:59.000Z

370

Observation of the submillimeter cosmic background spectrum  

SciTech Connect

An experimental measurement of the spectrum of the submillimeter cosmic background radiation is described. The experiment consists of measuring the night sky emission at an altitude of 39 km, correcting for the atmospheric molecular line emission, and placing limits on the contamination from sources of continuum radiation such as the apparatus itself and the earth. The observations were made on 24 July 1974 using a fully calibrated liquid-helium-cooled balloon- borne spectrophotometer. Important features of the apparatus include a cooled antenna, a polarizing interferometer, and a germanium bolometric detector. The characterization of the spectrophotometer includes the large angle response and emission of the antenna. The calibration of the instrument and corrections to the observed sky spectrum are based on measurements made during the flight. A simple model of the molecular line emission is used to determine the atmospheric contribution. The resulting spectrum covers the frequency range from 4 to 17 cm$sup -1$ and establishes that the cosmic background radiation follows the high frequency quantum cutoff for a 3K blackbody. A blackbody temperature of 2.99/sub -.$sub 14$/$sup +$.$sup 07$/K is deduced from our data. The present status of the cosmic background observations, which span more than three decades in frequency, is analyzed and it is concluded that they are all consistent with a blackbody temperature of 2.90 +- .04K (+- 1 SIGMA). This firmly supports the Big Bang cosmological model of the universe. (auth)

Woody, D.P.

1975-11-13T23:59:59.000Z

371

Microwave-Assisted Heterogeneous Catalytic Transesterification of Soybean Oil  

Science Conference Proceedings (OSTI)

Biodiesel, as a renewable bioenergy, recently has been researched in regard to biodiesel products. In this study, soybean oil was converted to biodiesel with methanol using several heterogeneous catalysts, furthermore, the process by means of microwave ... Keywords: Biodiesel, Transesterification, Microwave, Heterogeneous

Ming-Chien Hsiao; Pei-Hung Liao; Hsiu-Ling Hsu

2012-06-01T23:59:59.000Z

372

GIMS-based method for vegetation microwave monitoring  

Science Conference Proceedings (OSTI)

The objective of this paper is threefold: (1) To present a working methodology for the combined use of modeling technology and microwave remote-sensing measurements in the assessment of attenuation of electromagnetic waves by the vegetation cover; (2) ... Keywords: GIMS, Microwave, Remote sensing, Vegetative cover

Vladimir F. Krapivin; Anatolij M. Shutko; Alexander A. Chukhlantsev; Sergei P. Golovachev; Gary W. Phillips

2006-03-01T23:59:59.000Z

373

Microwave measurement of water content in flowing crude oil  

Science Conference Proceedings (OSTI)

A microwave method and a microwave device for measurement of water content in flowing crude oil are proposed. The method is based on measuring power of electromagnetic waves propagated through a transmission line and reflected from the load that is a ...

Yu. V. Makeev; A. P. Lifanov; A. S. Sovlukov

2013-01-01T23:59:59.000Z

374

Preliminary Design of an Industrial/Commercial Microwave Clothes Dryer  

Science Conference Proceedings (OSTI)

Drying fabrics with microwave energy can reduce both the drying time and the drying temperature. This process provides a new level of fabric care to make all fabrics last longer and look better. The purpose of designing a 125-pound commercial/industrial microwave dryer was to perform cost exercises and calculate payback periods.

1997-09-09T23:59:59.000Z

375

Microwave sintering of sol-gel derived abrasive grain  

DOE Patents (OSTI)

A method is provided for making microwave-sintered, free flowing alpha alumina-based ceramic abrasive grain, under conditions effective to couple microwaves with calcined alpha alumina-based abrasive gain precursor and sinter it at a temperature of at least about 1150.degree. C.

Plovnick, Ross (St. Louis Park, MN); Celikkaya, Ahmet (Woodbury, MN); Blake, Rodger D. (Tuscon, AZ)

1997-01-01T23:59:59.000Z

376

Microwave sintering of single plate-shaped articles  

DOE Patents (OSTI)

Apparatus and method for high temperature sintering of plate-shaped articles of alumina, magnesia, silica, yttria, zirconia, and mixtures thereof using microwave radiation. An article is placed within a sintering structure located within a sintering container which is placed in a microwave cavity for heating. The rates at which heating and cooling take place is controlled.

Katz, Joel D. (Los Alamos, NM); Blake, Rodger D. (Tucson, AZ)

1995-01-01T23:59:59.000Z

377

INEXPENSIVE, OFF THE SHELF HYBRID MICROWAVE SYSTEM  

Science Conference Proceedings (OSTI)

A hybrid-heating microwave oven provides the energy to heat small 10-gram samples of spent metal tritide storage bed material to release tenaciously held decay product {sup 3}He. Complete mass balance procedures require direct measurement of added or produced gases on a tritide bed, and over 1100 C is necessary to release deep trapped {sup 3}He. The decomposition of non-radioactive CaCO{sub 3} and the quantitative measurement of CO{sub 2} within 3% of stoichiometry demonstrate the capabilities of the apparatus to capture generated (released) gases.

Walters, T; Paul Burket, P; John Scogin, J

2007-06-21T23:59:59.000Z

378

DOE Vendor Communication Plan I. Background  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Vendor Communication Plan Vendor Communication Plan I. Background On February 2, 2011, the Office of Federal Procurement Policy (OFPP) issued a memorandum entitled "Myth-Busting: Addressing Misconceptions to Improve Communication with Industry during the Acquisition Process." In addition to identifying and refuting common misconceptions about vendor engagement, the memorandum directed agencies to develop high-level vendor communication plans to discuss how each agency will reduce unnecessary barriers, publicize communication opportunities, and prioritize engagement opportunities for high-risk, complex programs or those that fail to attract new vendors during re-competitions.

379

Cosmic string collision in cosmological backgrounds  

SciTech Connect

The collisions of cosmic string loops and the dynamics of junction formations in expanding backgrounds are studied. The key parameter controlling the dynamics of junction formation, the cosmic strings zipping and unzipping, is the relative size of the loops compared to the Hubble radius at the time of collision. We study analytically and numerically these processes for large superhorizon size loops, for small subhorizon size loops as well as for loops with the radii comparable to the Hubble radius at the time of collision.

Firouzjahi, Hassan [School of Physics, Institute for Research in Fundamental Sciences (IPM), P.O. Box 19395-5531, Tehran (Iran, Islamic Republic of); Khoeini-Moghaddam, Salomeh [School of Physics, Institute for Research in Fundamental Sciences (IPM), P.O. Box 19395-5531, Tehran (Iran, Islamic Republic of); Department of Physics, Faculty of Science, Tarbiat Mo'allem University, Tehran (Iran, Islamic Republic of); Khosravi, Shahram [Department of Physics, Faculty of Science, Tarbiat Mo'allem University, Tehran (Iran, Islamic Republic of); School of Astronomy, Institute for Research in Fundamental Sciences (IPM), P.O. Box 19395-5531, Tehran (Iran, Islamic Republic of)

2010-06-15T23:59:59.000Z

380

Decoherence in the cosmic background radiation  

E-Print Network (OSTI)

In this paper we analyze the possibility of detecting nontrivial quantum phenomena in observations of the temperature anisotropy of the cosmic background radiation (CBR), for example, if the Universe could be found in a coherent superposition of two states corresponding to different CBR temperatures. Such observations are sensitive to scalar primordial fluctuations but insensitive to tensor fluctuations, which are therefore converted into an environment for the former. Even for a free inflaton field minimally coupled to gravity, scalar-tensor interactions induce enough decoherence among histories of the scalar fluctuations as to render them classical under any realistic probe of their amplitudes.

Mariano Franco; Esteban Calzetta

2011-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "microwave background cmb" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Superconducting Hair on Charged Black String Background  

E-Print Network (OSTI)

Behaviour of Dirac fermions in the background of a charged black string penetrated by an Abelian Higgs vortex is elaborated. One finds the evidence that the system under consideration can support fermion fields acting like a superconducting cosmic string in the sence that a nontrivial Dirac fermion field can be carried by the system in question. The case of nonextremal and extremal black string vortex systems were considered. The influence of electric and Higgs charge, the winding number and the fermion mass on the fermion localization near the black string event horizon was studied. It turned out that the extreme charged black string expelled fermion fields more violently comparing to the nonextremal one.

Lukasz Nakonieczny; Marek Rogatko

2012-01-25T23:59:59.000Z

382

Emergence of oscillons in an expanding background  

Science Conference Proceedings (OSTI)

We consider a (1+1) dimensional scalar field theory that supports oscillons, which are localized, oscillatory, stable solutions to nonlinear equations of motion. We study this theory in an expanding background and show that oscillons now lose energy, but at a rate that is exponentially small when the expansion rate is slow. We also show numerically that a universe that starts with (almost) thermal initial conditions will cool to a final state where a significant fraction of the energy of the universe--on the order of 50%--is stored in oscillons. If this phenomenon persists in realistic models, oscillons may have cosmological consequences.

Farhi, E.; Guth, A. H.; Iqbal, N. [Center for Theoretical Physics, Laboratory for Nuclear Science, and Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Graham, N. [Center for Theoretical Physics, Laboratory for Nuclear Science, and Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Department of Physics, Middlebury College, Middlebury, Vermont 05753 (United States); Rosales, R. R. [Department of Mathematics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Stamatopoulos, N. [Department of Physics, Middlebury College, Middlebury, Vermont 05753 (United States)

2008-04-15T23:59:59.000Z

383

Microwave Plasma Monitoring System For Real-Time Elemental Analysis  

NLE Websites -- All DOE Office Websites (Extended Search)

Microwave Plasma Monitoring System For Real-Time Elemental Analysis Microwave Plasma Monitoring System For Real-Time Elemental Analysis Microwave Plasma Monitoring System For Real-Time Elemental Analysis The invention apparatus can also be used to monitor for the presence of halogens, sulfur and silicon. Available for thumbnail of Feynman Center (505) 665-9090 Email Microwave Plasma Monitoring System For Real-Time Elemental Analysis There has been invented a process for analyzing ambient air in a microwave induced plasma without use of an additional carrier gas. There has also been invented an apparatus for analyzing ambient air, other sample gas, or nebulized and desolvated liquids wherein a novel arrangement of plasma gas and sample gas conduits is used to enhance dependability of the plasma. This apparatus embodiment of the invention has a concentric arrangement of

384

Mobile system for microwave removal of concrete surfaces  

DOE Patents (OSTI)

A method and apparatus are disclosed for the microwave removal of contaminated concrete surfaces. The apparatus comprises a housing adapted to pass over a support surface. The housing includes a waveguide for directing microwave energy to the surface at an angle maximizing absorption of microwave energy by the surface. The apparatus is further provided with a source of microwave energy operably associated with the waveguide, wherein the microwave energy has a frequency of between about 10.6 GHz and about 24 GHz and acts to remove the uppermost layer from the surface. The apparatus further includes a debris containment assembly comprising a vacuum assembly operably associated with the housing. The vacuum assembly is adapted to remove debris from the area adjacent the surface. 7 figs.

White, T.L.; Bigelow, T.S.; Schaich, C.R.; Foster, D. Jr.

1997-06-03T23:59:59.000Z

385

Mobile system for microwave removal of concrete surfaces  

DOE Patents (OSTI)

A method and apparatus for the microwave removal of contaminated concrete surfaces. The apparatus comprises a housing adapted to pass over a support surface. The housing includes a waveguide for directing microwave energy to the surface at an angle maximizing absorption of microwave energy by the surface. The apparatus is further provided with a source of microwave energy operably associated with the waveguide, wherein the microwave energy has a frequency of between about 10.6 GHz and about 24 GHz and acts to remove the uppermost layer from the surface. The apparatus further includes a debris containment assembly comprising a vacuum assembly operably associated with the housing. The vacuum assembly is adapted to remove debris from the area adjacent the surface.

White, Terry L. (Oak Ridge, TN); Bigelow, Timothy S. (Knoxville, TN); Schaich, Charles R. (Lenoir City, TN); Foster, Jr., Don (Knoxville, TN)

1997-01-01T23:59:59.000Z

386

Coupled Electromagnetic and Thermal Modeling of Microwave Tissue Processing  

E-Print Network (OSTI)

This study deals with 3D finite element modeling of microwave tissue processing using Comsol software 4.0. Maxwell’s equations are coupled with heat conduction equation to determine electromagnetic field distribution and temperature profile within tissue sample in a reagent inside a domestic microwave oven. The microwave power generation term is calculated. Also, temperature distribution obtained is compared with experimental point measurements recorded in the centre of the tissue using a shielded K type thermocouple. Good agreement is found between numerical and experimental data. The effect of size of both reagent and tissue as well as tissue type on microwave heating patterns within tissue sample is investigated. Studies shows that the reagent volume has greater effect than other factors. The results of the study is considered as a basic foundation for development of coupled electromagnetic thermal models of microwave heating of tissue specimens. The model assists in choosing appropriate process parameters for achieving uniform temperature distribution within tissue specimen.

Osama A Hassan; Ahmed H K; Il Ences; Ahmed M El Bialy

2013-01-01T23:59:59.000Z

387

Container for heat treating materials in microwave ovens  

DOE Patents (OSTI)

The efficiency of a microwave oven of a conventional two-source configuration and energy level is increased by providing the oven with a container for housing a refractory material to be treated. The container is formed of top and bottom walls transparent to microwaves while the sidewalls, in a circular configuration, are formed of a nonmetallic material opaque to microwave radiation reflecting the radiation penetrating the top and bottom walls radially inwardly into the center of the container wherein a casket of heat-insulating material is provided for housing the material to be heat treated. The reflection of the microwave radiation from the sidewalls increases the concentration of the microwaves upon the material being heat treated while the casket retains the heat to permit the heating of the material to a substantially higher temperature than achieveable in the oven without the container.

Holcombe, Cressie E. (Farragut, TN); Dykes, Norman L. (Oak Ridge, TN); Kimrey, Jr., Harold D. (Knoxville, TN); Mills, James E. (Knoxville, TN)

1989-01-01T23:59:59.000Z

388

Electromagnetic polarizabilities: Lattice QCD in background fields  

Science Conference Proceedings (OSTI)

Chiral perturbation theory makes definitive predictions for the extrinsic behavior of hadrons in external electric and magnetic fields. Near the chiral limit, the electric and magnetic polarizabilities of pions, kaons, and nucleons are determined in terms of a few well-known parameters. In this limit, hadrons become quantum mechanically diffuse as polarizabilities scale with the inverse square-root of the quark mass. In some cases, however, such predictions from chiral perturbation theory have not compared well with experimental data. Ultimately we must turn to first principles numerical simulations of QCD to determine properties of hadrons, and confront the predictions of chiral perturbation theory. To address the electromagnetic polarizabilities, we utilize the background field technique. Restricting our attention to calculations in background electric fields, we demonstrate new techniques to determine electric polarizabilities and baryon magnetic moments for both charged and neutral states. As we can study the quark mass dependence of observables with lattice QCD, the lattice will provide a crucial test of our understanding of low-energy QCD, which will be timely in light of ongoing experiments, such as at COMPASS and HI gamma S.

W. Detmold, B.C. Tiburzi, A. Walker-Loud

2012-04-01T23:59:59.000Z

389

How soliton- anti soliton di quark pairs signify an Einstein constant dominated cosmology and facilitate reconstruction of initial dark matter contributions to CMB  

E-Print Network (OSTI)

We review the results of a model of how nucleation of a new universe occurs, assuming a di quark identification for soliton-anti soliton constituent parts of a scalar field. The intial potential system employed is semi classical in nature, becoming non-classical at the end of chaotic inflation at the same time cosmological expansion is dominated by the Einstein cosmological constant. We use Scherrer's derivation of a sound speed being zero during initial inflationary cosmology, and cange it afterwards as the slope of the scalar field moves away from a thin wall approximation. All this is to aid in a data reconstruction problem of how to account for the initial origins of CMB due to dark matter since effective field theories as presently constructed require a cut off value for applicability of their potential structure. This is often at the cost of, especially in early universe theoretical models, of clearly defined baryogenesis, and of a well defined mechanism of phase transitions. The material below is now a proposal, in part accepted as a point of discussion as a white paper (appropriately) submitted to the Dark Energy Task Force, in its mission to advise (through its parent committees) the NSF, NASA and DOE. This was for helping to select both ground-based and space-based techniques for analyzing data as well as recommending the science requirements for a space-based dark energy mission.

A. W. Beckwith

2005-10-04T23:59:59.000Z

390

Notices Background The National Wildlife Refuge System  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

89 Federal Register 89 Federal Register / Vol. 74, No. 223 / Friday, November 20, 2009 / Notices Background The National Wildlife Refuge System Administration Act of 1966 (16 U.S.C. 668dd-668ee) (Administration Act), as amended by the National Wildlife Refuge System Improvement Act of 1997, requires us to develop a CCP for each national wildlife refuge. The purpose for developing a CCP is to provide refuge managers with a 15-year plan for achieving refuge purposes and contributing toward the mission of the National Wildlife Refuge System, consistent with sound principles of fish and wildlife management, conservation, legal mandates, and our policies. In addition to outlining broad management direction on conserving wildlife and their habitats, CCPs identify wildlife-

391

ARM: Microwave Radiometer data (MWR Profiles - QME), water vapor, temp, cloud liquid water, precip water retrievals  

DOE Data Explorer (OSTI)

Microwave Radiometer data (MWR Profiles - QME), water vapor, temp, cloud liquid water, precip water retrievals

Maria Cadeddu

392

Modeling of Microwave Ovens with Perforated Metal Walls Erin M. Kiley and Vadim V. Yakovlev  

E-Print Network (OSTI)

engineers developing new microwaveable products. This can be explained by the particularly complex nature, modeling. I. INTRODUCTION While historically, technological progress in microwave power engineering has microwave ovens - the most widespread microwave heating devices - have not yet been notably adopted by food

Yakovlev, Vadim

393

Microwave processing improvements for methane conversion to ethylene  

DOE Green Energy (OSTI)

This is the final report of a one-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The project`s objective was to investigate microwave enhanced catalysis. Published work by others had demonstrated improved selectivity in microwave-driven catalytic conversion of 2-methylpentane to its isomers. We reproduced their experiment, discovering that there is no improvement in selectivity using microwaves. The selectivity at a given conversion was the same for both microwave heated and conventionally heated catalyst beds. Meetings with the authors of the previously published work led to the conjecture that their catalyst was not being prepared properly, leading to anomalously low selectivity for their conventional heating runs. An optical temperature diagnostic suitable for use on a microwave applicator was developed and characterized in this project. This pyrometer can measure the temperature of small scale features on the catalyst bed, and it has a fast response that can follow the rapid heating often encountered in a microwave processing system. The behavior of the microwave applicator system was studied, and theoretical models were developed to yield insight about the stability and control of the system.

Stringfield, R.; Ott, K.; Nelson, E.; Anderson, G.; Chen, Dye-Zone; Dyer, T. [Los Alamos National Lab., NM (United States); Thomas, J. [Virginia Polytechnic Inst. and State Univ., Blacksburg, VA (United States)

1997-08-01T23:59:59.000Z

394

Electron beam collector for a microwave power tube  

DOE Patents (OSTI)

This invention relates to a cylindrical, electron beam collector that efficiently couples the microwave energy out of a high power microwave source while stopping the attendant electron beam. The interior end walls of the collector are a pair of facing parabolic mirrors and the microwave energy from an input horn is radiated between the two mirrors and reassembled at the entrance to the output waveguide where the transmitted mode is reconstructed. The mode transmission through the collector of the present invention has an efficiency of at least 94%.

Dandl, Raphael A. (Oak Ridge, TN)

1980-01-01T23:59:59.000Z

395

Compact microwave ion source for industrial applications  

SciTech Connect

A 2.45 GHz microwave ion source for ion implanters has many good properties for industrial application, such as easy maintenance and long lifetime, and it should be compact for budget and space. But, it has a dc current supply for the solenoid and a rf generator for plasma generation. Usually, they are located on high voltage platform because they are electrically connected with beam extraction power supply. Using permanent magnet solenoid and multi-layer dc break, high voltage deck and high voltage isolation transformer can be eliminated, and the dose rate on targets can be controlled by pulse duty control with semiconductor high voltage switch. Because the beam optics does not change, beam transfer components, such as focusing elements and beam shutter, can be eliminated. It has shown the good performances in budget and space for industrial applications of ion beams.

Cho, Yong-Sub; Kim, Dae-Il; Kim, Han-Sung; Seol, Kyung-Tae; Kwon, Hyeok-Jung; Hong, In-Seok [Proton Engineering Frontier Project, Korea Atomic Energy Research Institute, Daejeon 305-353 (Korea, Republic of)

2012-02-15T23:59:59.000Z

396

Self-consistent microwave plasma heating rates  

SciTech Connect

Under conditions within a hot overdense plasma corona where the field frequency is much less than the electron plasma frequency and the field period is much less than the hydrodynamic expansion time it is shown that electron field reversal heating can exceed the combined classical heating rates due to inverse bremsstrahlung (skin effect) and field pressure (PdV) by a factor approximately v/ sub e//2v/sub i/ (half the ratio of electron and ion thermal velocities). In particular this rate can exceed the inertial expansion cooling rate at a collisionless corona density of approximately 1 percent solid core density and could be realized experimentally at core temperatures approximately 3--5 keV and microwave field intensities approximately 1 MG. (auth)

Ensley, D.L.; White, R.H.

1975-10-01T23:59:59.000Z

397

Microwave-Regenerated Diesel Exhaust Particulate Filter  

Science Conference Proceedings (OSTI)

Development of a microwave-regenerated particulate filter system has evolved from bench scale work to actual diesel engine experimentation. The filter system was initially evaluated on a stationary mounted 1.2-L diesel engine and was able to remove a significant amount of carbon particles from the exhaust. The ability of the microwave energy to regenerate or clean the filter was also demonstrated on this engine under idle conditions. Based on the 1.2-L experiments, improvements to the filter design and materials were implemented and the system was re-evaluated on a vehicle equipped with a 7.3-L diesel engine. The 7.3-L engine was selected to achieve heavy filter loading in a relatively short period of time. The purpose of these experiments was to evaluate filter-loading capacity, power requirements for regeneration, and filter regeneration efficiency. A more detailed evaluation of the filter was performed on a stationary mounted 1.9-L diesel engine. The effect of exhaust flow rate, loading, transients, and regeneration on filter efficiency was evaluated with this setup. In addition, gaseous exhaust emissions were investigated with and without an oxidation catalyst on the filter cartridge during loading and regeneration. (SAE Paper SAE-2001-01-0903 © 2001 SAE International. This paper is published on this website with permission from SAE International. As a user of this website, you are permitted to view this paper on-line, download this pdf file and print one copy of this paper at no cost for your use only. The downloaded pdf file and printout of this SAE paper may not be copied, distributed or forwarded to others or for the use of others.)

Nixdorf, Richard D. (Industrial Ceramic Solution, LLC); Green, Johney Boyd; Story, John M.; Wagner, Robert M. (Oak Ridge National Laboratory)

2001-03-05T23:59:59.000Z

398

../fusion/templates/mapguide/maroon/css/maroon_fusion.css background-image: url(../images/background.gif);  

E-Print Network (OSTI)

../fusion/templates/mapguide/maroon/css/maroon_fusion.css body { background-image: url(../images/background.gif); ../fusion/templates/mapguide/maroon/css/ maroon_fusion.css body { background-color: #3e5c5f; ../fusion/templates/mapguide/maroon/css/ maroon_fusion.css #ToolbarVertical { background: #500000; maroon_fusion.css #Toolbar { background

Ahmad, Sajjad

399

L4, Ultrafast Microwave-Stimulated Sculpting and Thermoelectric ...  

Science Conference Proceedings (OSTI)

... of sulfur doped, Bi2Te3, Bi2Se3, and Sb2Te3 by microwave-stimulation. ... which acts as both a shape-mediating agent as well as for dopant delivery.

400

Analytical scanning evanescent microwave microscope and control stage  

DOE Patents (OSTI)

A scanning evanescent microwave microscope (SEMM) that uses near-field evanescent electromagnetic waves to probe sample properties is disclosed. The SEMM is capable of high resolution imaging and quantitative measurements of the electrical properties of the sample. The SEMM has the ability to map dielectric constant, loss tangent, conductivity, electrical impedance, and other electrical parameters of materials. Such properties are then used to provide distance control over a wide range, from to microns to nanometers, over dielectric and conductive samples for a scanned evanescent microwave probe, which enable quantitative non-contact and submicron spatial resolution topographic and electrical impedance profiling of dielectric, nonlinear dielectric and conductive materials. The invention also allows quantitative estimation of microwave impedance using signals obtained by the scanned evanescent microwave probe and quasistatic approximation modeling. The SEMM can be used to measure electrical properties of both dielectric and electrically conducting materials.

Xiang, Xiao-Dong; Gao, Chen; Duewer, Fred; Yang, Hai Tao; Lu, Yalin

2013-01-22T23:59:59.000Z

Note: This page contains sample records for the topic "microwave background cmb" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Microwave plasma chemical vapor deposition of nano-composite...  

NLE Websites -- All DOE Office Websites (Extended Search)

plasma chemical vapor deposition of nano-composite CPt thin-films Title Microwave plasma chemical vapor deposition of nano-composite CPt thin-films Publication Type Journal...

402

Microwave Plasma Chemical Vapor Depositon of Nano-Structured...  

NLE Websites -- All DOE Office Websites (Extended Search)

Plasma Chemical Vapor Depositon of Nano-Structured SnC Composite Thin-Film anodes for Li-ion Battteries Title Microwave Plasma Chemical Vapor Depositon of Nano-Structured SnC...

403

Heterogeneous breast phantom development for microwave imaging using regression models  

Science Conference Proceedings (OSTI)

As new algorithms for microwave imaging emerge, it is important to have standard accurate benchmarking tests. Currently, most researchers use homogeneous phantoms for testing new algorithms. These simple structures lack the heterogeneity of the dielectric ...

Camerin Hahn; Sima Noghanian

2012-01-01T23:59:59.000Z

404

High-precision optical and microwave signal synthesis and distribution  

E-Print Network (OSTI)

In this thesis, techniques for high-precision synthesis of optical and microwave signals and their distribution to remote locations are presented. The first topic is ultrafast optical pulse synthesis by coherent superposition ...

Kim, Jung-Won, 1976-

2007-01-01T23:59:59.000Z

405

Field Performance of a Spinning-Reflector Microwave Radiometer  

Science Conference Proceedings (OSTI)

In the winter of 1986, two microwave radiometers were operated side by side at a high-altitude weather observation site in the central Sierra Nevada for the purpose of comparing measurements in a variety of ambient weather conditions. The ...

Belay B. Demoz; Arlen W. Huggins; Joseph A. Warburton; Richard L. Smith

1993-06-01T23:59:59.000Z

406

Frontal Rainfall Observation by a Commercial Microwave Communication Network  

Science Conference Proceedings (OSTI)

A novel approach for reconstruction of rainfall spatial–temporal dynamics from a wireless microwave network is presented. It employs a stochastic space–time model based on a rainfall advection model, assimilated using a Kalman filter. The ...

Artem Zinevich; Hagit Messer; Pinhas Alpert

2009-07-01T23:59:59.000Z

407

Evaluation of Passive Microwave Precipitation Algorithms in Wintertime Midlatitude Situations  

Science Conference Proceedings (OSTI)

The second intercomparison project of the Global Precipitation Climatology Project examined the estimation of midlatitude, cool-season precipitation. As part of that effort, the authors report here on the results of two microwave techniques the ...

Andrew J. Negri; Eric J. Nelkin; Robert F. Adler; George J. Huffman; Christian Kummerow

1995-02-01T23:59:59.000Z

408

Correcting Microwave Precipitation Retrievals for near-Surface Evaporation  

E-Print Network (OSTI)

This paper compares two methods for correcting passive or active microwave surface precipitation estimates based on hydrometeors sensed aloft that may evaporate before landing. These corrections were derived using two years ...

Surussavadee, Chinnawat

409

Temperature Profiling with Neural Network Inversion of Microwave Radiometer Data  

Science Conference Proceedings (OSTI)

A neural network is used to obtain vertical profiles of temperature from microwave radiometer data. The overall rms error in the retrieved profiles of a test dataset was only about 8% worse than the overall error using an optimized statistical ...

James H. Churnside; Thomas A. Stermitz; Judith A. Schroeder

1994-02-01T23:59:59.000Z

410

A Screening Methodology for Passive Microwave Precipitation Retrieval Algorithms  

Science Conference Proceedings (OSTI)

The success of any passive microwave precipitation retrieval algorithm relies on the proper identification of rain areas and the elimination of surface areas that produce a signature similar to that of precipitation. A discussion on the impact of ...

Ralph R. Ferraro; Eric A. Smith; Wesley Berg; George J. Huffman

1998-05-01T23:59:59.000Z

411

Passive Microwave Brightness Temperatures as Proxies for Hailstorms  

Science Conference Proceedings (OSTI)

The Tropical Rainfall Measuring Mission (TRMM) satellite has been used to infer distributions of intense thunderstorms. Besides the lightning measurements from TRMM, the radar reflectivities and passive microwave brightness temperatures have been ...

Daniel J. Cecil

2009-06-01T23:59:59.000Z

412

Quantifying Global Uncertainties in a Simple Microwave Rainfall Algorithm  

Science Conference Proceedings (OSTI)

While a large number of methods exist in the literature for retrieving rainfall from passive microwave brightness temperatures, little has been written about the quantitative assessment of the expected uncertainties in these rainfall products at ...

Christian Kummerow; Wesley Berg; Jody Thomas-Stahle; Hirohiko Masunaga

2006-01-01T23:59:59.000Z

413

Neural network microwave precipitation retrievals and modeling results  

E-Print Network (OSTI)

We describe a simulation methodology used to develop and validate precipitation retrieval algorithms for current and future passive microwave sounders with emphasis on the NPOESS (National Polar-orbiting Operational ...

Leslie, R. Vincent

414

Analytical scanning evanescent microwave microscope and control stage  

DOE Patents (OSTI)

A scanning evanescent microwave microscope (SEMM) that uses near-field evanescent electromagnetic waves to probe sample properties is disclosed. The SEMM is capable of high resolution imaging and quantitative measurements of the electrical properties of the sample. The SEMM has the ability to map dielectric constant, loss tangent, conductivity, electrical impedance, and other electrical parameters of materials. Such properties are then used to provide distance control over a wide range, from to microns to nanometers, over dielectric and conductive samples for a scanned evanescent microwave probe, which enable quantitative non-contact and submicron spatial resolution topographic and electrical impedance profiling of dielectric, nonlinear dielectric and conductive materials. The invention also allows quantitative estimation of microwave impedance using signals obtained by the scanned evanescent microwave probe and quasistatic approximation modeling. The SEMM can be used to measure electrical properties of both dielectric and electrically conducting materials.

Xiang, Xiao-Dong (Danville, CA); Gao, Chen (Anhui, CN); Duewer, Fred (Albany, CA); Yang, Hai Tao (Albany, CA); Lu, Yalin (Chelmsford, MA)

2009-06-23T23:59:59.000Z

415

In situ noncombustive microwave processing of oil shale. Final report  

SciTech Connect

A unified analytical examination of the products of microwave oil shale has been completed. A sample of subituminous Colorado coal was also included. Analysis systems have been planned, constructed and placed into operation so as to provide a definitive profile of the composition of gases, oil, and water released by the microwave heated oil shale and coal samples. In a previous NSF study, it was reported that microwave retorted oil shale produced large quantities of high BTU content gas. In the data presented in this report, using a modular microcoulometric analysis system, a definitive profile of the composition of the gases, oil, and water, released by the microwave retorted oil shale and coal show that the previous results are confirmed.

Wall, E.T.

1979-08-31T23:59:59.000Z

416

Overland Precipitation Estimation from TRMM Passive Microwave Observations  

Science Conference Proceedings (OSTI)

Procedures for passive microwave precipitation estimation over land are investigated based on a large database of Tropical Rainfall Measuring Mission (TRMM) observations. The procedures include components for rain area delineation, convective/...

Mircea Grecu; Emmanouil N. Anagnostou

2001-08-01T23:59:59.000Z

417

Degradation of Radar Reflectivity by Cloud Attenuation at Microwave Frequency  

Science Conference Proceedings (OSTI)

The main object of this paper is to emphasize that clouds—the nonprecipitating component of condensed atmospheric water—can produce a strong attenuation at operational microwave frequencies, although they present a low reflectivity preventing ...

Olivier Pujol; Jean-François Georgis; Laurent Féral; Henri Sauvageot

2007-04-01T23:59:59.000Z

418

Microwave Dielectric Heating of Drops in Microfluidic Devices  

E-Print Network (OSTI)

We present a technique to locally and rapidly heat water drops in microfluidic devices with microwave dielectric heating. Water absorbs microwave power more efficiently than polymers, glass, and oils due to its permanent molecular dipole moment that has a large dielectric loss at GHz frequencies. The relevant heat capacity of the system is a single thermally isolated picoliter drop of water and this enables very fast thermal cycling. We demonstrate microwave dielectric heating in a microfluidic device that integrates a flow-focusing drop maker, drop splitters, and metal electrodes to locally deliver microwave power from an inexpensive, commercially available 3.0 GHz source and amplifier. The temperature of the drops is measured by observing the temperature dependent fluorescence intensity of cadmium selenide nanocrystals suspended in the water drops. We demonstrate characteristic heating times as short as 15 ms to steady-state temperatures as large as 30 degrees C above the base temperature of the microfluidi...

Issadore, David; Brown, Keith A; Sandberg, Lori; Weitz, David; Westervelt, Robert M

2009-01-01T23:59:59.000Z

419

A plasma source for system for microwave plasma experiments (SYMPLE)  

Science Conference Proceedings (OSTI)

A system "SYMPLE" is being developed at our laboratory to investigate the interaction of high power microwave and plasma. A brief account on the development of a plasma source that satisfies the prerequisites required for SYMPLE is discussed.

V. P. Anitha; Renu Bahl; Priyavandna J. Rathod; Jayesh Raval; Y. C. Saxena

2011-02-01T23:59:59.000Z

420

A Dual-Frequency Microwave Technique for Measuring Rainwater Content  

Science Conference Proceedings (OSTI)

While there are many microwave techniques for estimating the rainfall rate, there are presently few if any for accurately determining the rainwater content (W). This study shows that the dual-frequency (38, 25 GHZ) differential attenuation (A38?...

A. R. Jameson

1992-02-01T23:59:59.000Z

Note: This page contains sample records for the topic "microwave background cmb" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Integrating giant microwave absorption with magnetic refrigeration in one  

E-Print Network (OSTI)

Integrating giant microwave absorption with magnetic refrigeration in one multifunctional with magnetic refrigeration in one multifunctional material. This integration not only advances our EMI problem, it is becoming very urgent to design and fabricate the electromagnetic compatibility (EMC

Wang, Wei Hua

422

On the forward scattering of microwave breast imaging  

Science Conference Proceedings (OSTI)

Microwave imaging for breast cancer detection has been of significant interest for the last two decades. Recent studies focus on solving the imaging problem using an inverse scattering approach. Efforts have mainly been focused on the development of ...

Hoi-Shun Lui; Andreas Fhager; Mikael Persson

2012-01-01T23:59:59.000Z

423

Tomographic Reconstruction of Rainfall Fields through Microwave Attenuation Measurements  

Science Conference Proceedings (OSTI)

A new method is presented for estimating the space-time rainfall intensity distribution at ground level over a limited area. This is based on a tomographic technique that exploits the relationship between microwave attenuation and rainfall ...

D. Giuli; A. Toccafondi; G. Biffi Gentili; A. Freni

1991-09-01T23:59:59.000Z

424

Development of a Microwave Clothes Dryer: Interim Report I  

Science Conference Proceedings (OSTI)

The development of a microwave clothes dryer has the potential to bring significant consumer benefits to this appliance. Efficient, short drying cycles are possible for both normal and delicate fabrics. The first year of development is described here.

1993-07-24T23:59:59.000Z

425

Retrieval of Ice Cloud Parameters Using a Microwave Imaging Radiometer  

Science Conference Proceedings (OSTI)

Based on the radiative transfer theory, the microwave radiance emanating from ice clouds at arbitrary viewing angles is expressed as an analytic function of the cloud ice water path (IWP), the particle effective diameter (De), and the particle ...

Fuzhong Weng; Norman C. Grody

2000-04-01T23:59:59.000Z

426

A Bayesian Approach to Microwave Precipitation Profile Retrieval  

Science Conference Proceedings (OSTI)

A multichannel passive microwave precipitation retrieval algorithm is developed. Bayes theorem is used to combine statistical information from numerical cloud models with forward radiative transfer modeling. Amultivariate lognormal prior ...

K. Franklin Evans; Joseph Turk; Takmeng Wong; Graeme L. Stephens

1995-01-01T23:59:59.000Z

427

Synthesis of Titanium Dioxide by Microwave Solid State Method and ...  

Science Conference Proceedings (OSTI)

In this work, titanium dioxide was synthetized by microwave solid-state ... Properties of Low-Carbon High-strength and Low-yield Ratio Bainitic Steels ... New Methodology of Enhancing Etching Factor of Copper Pattern for Advanced Packages.

428

Hydrometeor Retrieval Accuracy Using Microwave Window and Sounding Channel Observations  

Science Conference Proceedings (OSTI)

The retrieval errors of cloud and precipitation hydrometeor contents from spaceborne observations are estimated at microwave frequencies in atmospheric windows between 18 and 150 GHz and in oxygen absorption complexes near 50–60 and 118 GHz. The ...

Peter Bauer; Emmanuel Moreau; Sabatino Di Michele

2005-07-01T23:59:59.000Z

429

Surface wave multipath signals in near-field microwave imaging  

Science Conference Proceedings (OSTI)

Microwave imaging techniques are prone to signal corruption from unwanted multipath signals. Near-field systems are especially vulnerable because signals can scatter and reflect from structural objects within or on the boundary of the imaging zone. These ...

Paul M. Meaney; Fridon Shubitidze; Margaret W. Fanning; Maciej Kmiec; Neil R. Epstein; Keith D. Paulsen

2012-01-01T23:59:59.000Z

430

Using the Special Sensor Microwave Imager to Monitor Surface Wetness  

Science Conference Proceedings (OSTI)

The frequencies flown on the Special Sensor Microwave Imager (SSM/I) are sensitive to liquid water near the earth's surface. These frequencies are primarily atmospheric window channels, which receive the majority of their radiation from the ...

Alan Basist; Claude Williams Jr.; Thomas F. Ross; Matthew J. Menne; Norman Grody; Ralph Ferraro; Samuel Shen; Alfred T. C. Chang

2001-06-01T23:59:59.000Z

431

Constraining Microwave Brightness Temperatures by Radar Brightband Observations  

Science Conference Proceedings (OSTI)

Multichannel microwave sensors make it possible to construct physically based rainfall retrieval algorithms. In these schemes, errors arising from the inaccuracy of the physical modeling of the cloud system under observation have to be accounted ...

A. Battaglia; C. Kummerow; Dong-Bin Shin; C. Williams

2003-06-01T23:59:59.000Z

432

Estimating the Uncertainty in Passive-Microwave Rain Retrievals  

Science Conference Proceedings (OSTI)

Current passive-microwave rain-retrieval methods are largely based on databases built offline using cloud models. Since the vertical distribution of hydrometeors within the cloud has a large impact on upwelling brightness temperatures, a forward ...

Dorothée Coppens; Ziad S. Haddad; Eastwood Im

2000-12-01T23:59:59.000Z

433

Ground-Based Passive Microwave Profiling during Dynamic Weather Conditions  

Science Conference Proceedings (OSTI)

Short-period (1–5 min) temperature and humidity soundings up to 10-km height are retrieved from ground-based 12-channel microwave radiometer profiler (MWRP) observations. In contrast to radiosondes, the radiometric retrievals provide very high ...

K. R. Knupp; T. Coleman; D. Phillips; R. Ware; D. Cimini; F. Vandenberghe; J. Vivekanandan; E. Westwater

2009-06-01T23:59:59.000Z

434

The atom completed and a new particle  

E-Print Network (OSTI)

that the observed CMB will exhibit a blackbody radiation spectrum. The Cos- mic Background Explorer (COBE

Murayama, Hitoshi

435

Cosmological science enabled by Planck  

E-Print Network (OSTI)

Planck will be the first mission to map the entire cosmic microwave background (CMB) sky with mJy sensitivity and resolution better than 10'. The science enabled by such a mission spans many areas of astrophysics and cosmology. In particular it will lead to a revolution in our understanding of primary and secondary CMB anisotropies, the constraints on many key cosmological parameters will be improved by almost an order of magnitude (to sub-percent levels) and the shape and amplitude of the mass power spectrum at high redshift will be tightly constrained.

Martin White

2006-06-27T23:59:59.000Z

436

Characterization of background reflectivity for MEDUSA  

Science Conference Proceedings (OSTI)

The DARPA MEDUSA program goal is to detect, locate, and identify electro-optical threats in the vicinity of a moving platform. Laser sensing will be employed to find these threats by looking for anomalous reflections from threat sensors. However, the reflectivity variability (clutter) in both natural and manmade backgrounds will inherently limit target detection levels. In parallel with advanced component development by several aerospace contractors, a study of this clutter limitation was initiated in the long-wave (LW) and midwave (MW) infrared spectral regions to properly drive system design parameters. The analysis of clutter and associated limits on detection has been a major component of LANL efforts in laser remote sensing for non-proliferation. LANL is now analyzing existing data and conducting additional selected measurements in both the LWIR (9 and 10.6 pm) and MWIR (4.6 pm) in support of the DARPA program to increase our understanding of these clutter limitations and, thereby aid in the design and development of the MEDUSA system. The status of the LANL effort will be discussed. A variety of different natural and manmade target types have been investigated. Target scenes range from relatively low clutter sites typical of a southwestern desert to higher clutter downtown urban sites. Images are created by conducting raster scans across a scene interest. These images are then analyzed using data clustering techniques (e g K-means) to identify regions within the scene that contain similar reflectivity profiles. Data will be presented illustrating the reflectivity variability among different samples of the same target type, Le. within the same cluster, and among different data clusters. In general, it is found that the variability of reflectivities among similar targets is well represented by a log-normal distribution. Furthermore, manmade target tend to have higher reflectivities and more variability than natural targets. The implications of this observation for MEDUSA systems designed to locate and identify threat sensors will be discussed. The implications for chemical sensing applications will also be addressed.

Oldenborg, R. C. (Richard C.); Tiee, J. J. (Joe J.); Foy, B. R. (Bernard R.); Petrin, R. R. (Roger R.); Wilson, C. W. (Carl W.)

2003-01-01T23:59:59.000Z

437

SEARCH F O R LINEAR POLARIZATION O F THE COSMIC BACKGROUND RADIATION  

NLE Websites -- All DOE Office Websites (Extended Search)

SEARCH F SEARCH F O R LINEAR POLARIZATION O F THE COSMIC BACKGROUND RADIATION P h i l M. Lubin and George F. Smoot Space Sciences L a b o r a t o r y and Lawrence Berkeley L a b o r a t o r y U n i v e r s i t y of C a l i f o r n i a Berkeley, C a l i f o r n i a 94720 Received ABSTRACT W e p r e s e n t p r e l i m i n a r y measurements of t h e l i n e a r p o l a r i z a t i o n of t h e cosmic microwave background ( 3 ° K blackbody) r a d i a t i o n . These ground-based measurements a r e made a t 9 mm wavelength. W e f i n d no e v i d e n c e f o r l i n e a r p o l a r i z a t i o n , and s e t a n upper l i m i t f o r a p o l a r i z e d component of 0.8 m°K with a 95% confidence l e v e l . T h i s i m p l i e s t h a t t h e p r e s e n t rate of e x p a n s i o n of t h e Universe i s i s o t r o p i c t o one p a r t i n 1 0 , assuming no r e - i o n i z a t i o n of t h e p r i m o r d i a l plasma a f t e r recombination. 6 The observed cosmic microwave background r

438

Fuel gas production by microwave plasma in liquid  

Science Conference Proceedings (OSTI)

We propose to apply plasma in liquid to replace gas-phase plasma because we expect much higher reaction rates for the chemical deposition of plasma in liquid than for chemical vapor deposition. A reactor for producing microwave plasma in a liquid could produce plasma in hydrocarbon liquids and waste oils. Generated gases consist of up to 81% hydrogen by volume. We confirmed that fuel gases such as methane and ethylene can be produced by microwave plasma in liquid.

Nomura, Shinfuku; Toyota, Hiromichi; Tawara, Michinaga; Yamashita, Hiroshi; Matsumoto, Kenya [Graduate School of Science and Engineering, Ehime University, 3 Bunkyo-cho, Matsuyama, Ehime 790-8577 (Japan); Shikoku Industry and Technology Promotion Center, 2-5 Marunouchi, Takamatsu, Kagawa 760-0033 (Japan)

2006-06-05T23:59:59.000Z

439

Effects of localized microwave exposure on the dog thyroid  

SciTech Connect

The effects of localized microwave (2.45 GHz, CW) exposure of the dog thyroid gland were investigated. A dielectrically loaded waveguide applicator was designed and fabricated which efficiencly couples microwave energy to a small (2.54 cm x 5.08 cm) area of biological tissue. The function of the thyroid gland was assessed by the measurement of total plasma thyroxine (T4) using a radioimmunoassay.

Magin, R.L.

1976-01-01T23:59:59.000Z

440

Uniform bulk Material Processing using Multimode Microwave Radiation  

DOE Patents (OSTI)

An apparatus for generating uniform heating in material contained in a cylindrical vessel is described. TE{sub 10}-mode microwave radiation is coupled into a cylindrical microwave transition such that microwave radiation having TE{sub 11}-, TE{sub 01}- and TM{sub 01}-cylindrical modes is excited therein. By adjusting the intensities of these modes, substantially uniform heating of materials contained in a cylindrical drum which is coupled to the microwave transition through a rotatable choke can be achieved. The use of a poor microwave absorbing insulating cylindrical insert, such as aluminum oxide, for separating the material in the container from the container walls and for providing a volume through which air is circulated is expected to maintain the container walls at room temperature. The use of layer of highly microwave absorbing material, such as SiC, inside of the insulating insert and facing the material to be heated is calculated to improve the heating pattern of the present apparatus.

Varma, Ravi; Vaughan, Worth E.

1999-06-18T23:59:59.000Z

Note: This page contains sample records for the topic "microwave background cmb" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Development of A Microwave Assisted Particulate Filter Regeneration System  

DOE Green Energy (OSTI)

The need for active regeneration of diesel particulate filters and the advantages of microwave assisted regeneration are discussed. The current study has multiple objectives, which include developing a microwave assisted particulate filter regeneration system for future generation light-duty diesel applications, including PNGV type applications. A variable power 2.0 kW microwave system and a tuned waveguide were employed. Cavity geometry is being optimized with the aid of computational modeling and temperature measurements during microwave heating. A wall-flow ceramic-fiber filter with superior thermal shock resistance, high filtration efficiency, and high soot capacity was used. The microwave assisted particulate filter regeneration system has operated for more than 100 hours in an engine test-cell with a 5.9-liter diesel engine with automated split exhaust flow and by-pass flow capabilities. Filter regeneration was demonstrated using soot loads up to 10 g/liter and engine exhaust at idling flow rates as the oxygen source. A parametric study to determine the optimal combination of soot loading, oxidant flow rate, microwave power and heating time is underway. Preliminary experimental results are reported.

Popuri, Sriram

2001-08-05T23:59:59.000Z

442

Uniform bulk material processing using multimode microwave radiation  

DOE Patents (OSTI)

An apparatus for generating uniform heating in material contained in a cylindrical vessel is described. TE.sub.10 -mode microwave radiation is coupled into a cylindrical microwave transition such that microwave radiation having TE.sub.11 -, TE.sub.01 - and TM.sub.01 -cylindrical modes is excited therein. By adjusting the intensities of these modes, substantially uniform heating of materials contained in a cylindrical drum which is coupled to the microwave transition through a rotatable choke can be achieved. The use of a poor microwave absorbing insulating cylindrical insert, such as aluminum oxide, for separating the material in the container from the container walls and for providing a volume through which air is circulated is expected to maintain the container walls at room temperature. The use of layer of highly microwave absorbing material, such as SiC, inside of the insulating insert and facing the material to be heated is calculated to improve the heating pattern of the present apparatus.

Varma, Ravi (Los Alamos, NM); Vaughn, Worth E. (Madison, WI)

2000-01-01T23:59:59.000Z

443

Method and device for microwave sintering large ceramic articles  

DOE Patents (OSTI)

A microwave sintering system and method are provided for extremely uniform sintering of large and/or irregular shaped ceramic articles at microwave frequencies of at least 28 GHz in the hundreds of kilowatts power range in an untuned cavity. A 28 GHz, 200 kw gyrotron with variable power output is used as the microwave source connected to an untuned microwave cavity formed of an electrically conductive housing through an overmoded waveguide arrangement which acts in conjunction with a mode promoter within the cavity to achieve unexpected field uniformity. The part to be sintered is placed in the cavity and supported on a removable high temperature table in a central location within the cavity. The part is surrounded by a microwave transparent bulk insulating material to reduce thermal heat loss at the part surfaces and maintain more uniform temperature. The cavity may be operated at a high vacuum to aid in preventing arcing. The system allows controlled increased heating rates of greater than 200.degree. C./min to provide rapid heating of a ceramic part to a selected sintering temperature where it is maintained by regulating the microwave power applied to the part. As a result of rapid heating, the extent of non-isothermal processes such as segregation of impurities to the grain boundaries are minimized and exaggerated grain growth is reduced, thereby strengthening the mechanical properties of the ceramic part being sintered.

Kimrey, Jr., Harold D. (Knoxville, TN)

1990-01-01T23:59:59.000Z

444

A device for microwave sintering large ceramic articles  

DOE Patents (OSTI)

A microwave sintering system is provided for uniform sintering of large and/or irregular shapes ceramic articles at microwave frequencies of at least 28 GHz in the hundreds of kilowatts power range in an untuned cavity. A 28 GHz, 200 kw gyrotron with variable power output is used as the microwave source connected to an untuned microwave cavity formed of an electrically conductive housing. The part to be sintered is placed in the cavity and supported on a removable high temperature table in a central location within the cavity. The part is surrounded by a microwave transparent bulk insulating material to reduce thermal heat loss at the part surfaces and maintain more uniform temperature. The cavity may be operated at a high vacuum to aid in preventing arcing. The system allows controlled increased heating rates of greater than 200/degree/C/min to provide rapid heating of a ceramic part to a selected sintering temperature where it is maintained by regulating the microwave power applied to the part. As a result of rapid heating, the extent on non-isothermal processes such as segregation of impurities to the grain boundaries are minimized and exaggerated grain growth is reduced, thereby strengthening the mechanical properties of the ceramic part being sintered. 1 fig.

Kimrey, H.D. Jr.

1987-07-24T23:59:59.000Z

445

Temporal Variations of Land Surface Microwave Emissivities over the Atmospheric Radiation Measurement Program Southern Great Plains Site  

Science Conference Proceedings (OSTI)

Land surface microwave emissivities are important geophysical parameters for atmospheric, hydrological, and biospheric studies. This study estimates land surface microwave emissivity using an atmospheric microwave radiative transfer model and a ...

Bing Lin; Patrick Minnis

2000-07-01T23:59:59.000Z

446

The Impact of Spatial Resolution Enhancement of SSM/I Microwave Brightness Temperatures on Rainfall Retrieval Algorithms  

Science Conference Proceedings (OSTI)

The impact of spatial resolution enhancement on estimates of tropical typhoon rainfall based on SSM/1 (Special Sensor Microwave/Imager) measurements is evaluated with six different microwave precipitation retrieval algorithms. Passive microwave ...

Michael R. Farrar; Eric A. Smith; Xuwu Xiang

1994-03-01T23:59:59.000Z

447

Generating Single Microwave Photons in a Circuit  

E-Print Network (OSTI)

Electromagnetic signals in circuits consist of discrete photons, though conventional voltage sources can only generate classical fields with a coherent superposition of many different photon numbers. While these classical signals can control and measure bits in a quantum computer (qubits), single photons can carry quantum information, enabling non-local quantum interactions, an important resource for scalable quantum computing. Here, we demonstrate an on-chip single photon source in a circuit quantum electrodynamics (QED) architecture, with a microwave transmission line cavity that collects the spontaneous emission of a single superconducting qubit with high efficiency. The photon source is triggered by a qubit rotation, as a photon is generated only when the qubit is excited. Tomography of both qubit and fluorescence photon shows that arbitrary qubit states can be mapped onto the photon state, demonstrating an ability to convert a stationary qubit into a flying qubit. Both the average power and voltage of the photon source are characterized to verify performance of the system. This single photon source is an important addition to a rapidly growing toolbox for quantum optics on a chip.

A. A. Houck; D. I. Schuster; J. M. Gambetta; J. A. Schreier; B. R. Johnson; J. M. Chow; J. Majer; L. Frunzio; M. H. Devoret; S. M. Girvin; R. J. Schoelkopf

2007-02-27T23:59:59.000Z

448

Building Technologies Office: Home Energy Score Research and Background  

NLE Websites -- All DOE Office Websites (Extended Search)

Research and Background to someone by E-mail Research and Background to someone by E-mail Share Building Technologies Office: Home Energy Score Research and Background on Facebook Tweet about Building Technologies Office: Home Energy Score Research and Background on Twitter Bookmark Building Technologies Office: Home Energy Score Research and Background on Google Bookmark Building Technologies Office: Home Energy Score Research and Background on Delicious Rank Building Technologies Office: Home Energy Score Research and Background on Digg Find More places to share Building Technologies Office: Home Energy Score Research and Background on AddThis.com... About Take Action to Save Energy Partner With DOE Activities Solar Decathlon Building America Home Energy Score Get Involved Partners Research & Background

449

A Tutorial on Basic Principles of Microwave Reflectometry Applied to Fluctuation Measurements in Fusion Plasmas  

SciTech Connect

Microwave reflectometry is now routinely used for probing the structure of magnetohydrodynamic and turbulent fluctuations in fusion plasmas. Conditions specific to the core of tokamak plasmas, such as small amplitude of density irregularities and the uniformity of the background plasma, have enabled progress in the quantitative interpretation of reflectometer signals. In particular, the extent of applicability of the 1-D [one-dimensional] geometric optics description of the reflected field is investigated by direct comparison to 1-D full wave analysis. Significant advances in laboratory experiments are discussed which are paving the way towards a thorough understanding of this important measurement technique. Data is presented from the Tokamak Fusion Test Reactor [R. Hawryluk, Plasma Physics and Controlled Fusion 33 (1991) 1509] identifying the validity of the geometric optics description of the scattered field and demonstrating the feasibility of imaging turbulent fluctuations in fusion scale devices.

Nazikian, R.; Kramer, G.J.; Valeo, E.

2001-02-16T23:59:59.000Z

450

Reversible and efficient conversion between microwave and optical light  

E-Print Network (OSTI)

Converting low-frequency electrical signals into much higher frequency optical signals has enabled modern communications networks to leverage both the strengths of microfabricated electrical circuits and optical fiber transmission, allowing information networks to grow in size and complexity. A microwave-to-optical converter in a quantum information network could provide similar gains by linking quantum processors via low-loss optical fibers and enabling a large-scale quantum network. However, no current technology can convert low-frequency microwave signals into high-frequency optical signals while preserving their fragile quantum state. For this demanding application, a converter must provide a near-unitary transformation between different frequencies; that is, the ideal transformation is reversible, coherent, and lossless. Here we demonstrate a converter that reversibly, coherently, and efficiently links the microwave and optical portions of the electromagnetic spectrum. We use our converter to transfer classical signals between microwave and optical light with conversion efficiencies of ~10%, and achieve performance sufficient to transfer quantum states if the device were further precooled from its current 4 kelvin operating temperature to below 40 millikelvin. The converter uses a mechanically compliant membrane to interface optical light with superconducting microwave circuitry, and this unique combination of technologies may provide a way to link distant nodes of a quantum information network.

R. W. Andrews; R. W. Peterson; T. P. Purdy; K. Cicak; R. W. Simmonds; C. A. Regal; K. W. Lehnert

2013-10-19T23:59:59.000Z

451

Microwave Power Beaming Infrastructure for Manned Lightcraft Operations: Part 2  

SciTech Connect

In the past {approx}7 years, microwave gyrotron technology has rapidly evolved to a critical threshold wherein ultra-energetic space launch missions based on beamed energy propulsion (BEP) now appear eminently feasible. Over the next 20 years, hundred megawatt-class microwave power-beaming stations could be prototyped on high deserts and 3- to 4 km mountain peaks before migrating into low Earth orbit, along with their passive microwave relay satellites. Described herein is a 20 GW rechargeable nuclear power satellite and microwave power-beaming infrastructure designed for manned space launch operations in the year 2025. The technological readiness of 2500 GJ superconducting magnetic energy storage 'batteries', 433-m ultralight space structures, 100 MW liquid droplet radiators, 1-6+ MW gyrotron sources, and mega-scale arrays (e.g., 3000 phase-locked units) is addressed. Microwave BEP is 'breakthrough' technology with the very real potential to radically reduce space access costs by factors of 100 to 1000 in the forseeable future.

Myrabo, Leik N. [Lightcraft Technologies, Inc., Bennington, VT (United States)

2008-04-28T23:59:59.000Z

452

Advanced Rain/No-Rain Classification Methods for Microwave Radiometer Observations over Land  

Science Conference Proceedings (OSTI)

Seto et al. developed rain/no-rain classification (RNC) methods over land for the Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI). In this study, the methods are modified for application to other microwave radiometers. The ...

Shinta Seto; Takuji Kubota; Nobuhiro Takahashi; Toshio Iguchi; Taikan Oki

2008-11-01T23:59:59.000Z

453

Quantitative Measurements of Path-Integrated Rain Rate by an Airborne Microwave Radiometer over the Ocean  

Science Conference Proceedings (OSTI)

Data on the airborne microwave radiometer, which is one of the sensors of the airborne microwave rain-scatterometer/radiometer (AMRS) system, are analyzed to infer path-integrated rain rate measured from topside. The equation of radiative ...

Masaharu Fujita; Ken'ichi Okamoto; Harunobu Masuko; Takeyuki Ojima; Nobuyoshi Fugono

1985-09-01T23:59:59.000Z

454

Simulation of Microwave Brightness Temperatures of an Evolving Hailstorm at SSM/I Frequencies  

Science Conference Proceedings (OSTI)

A simulation of the appearance of an intense hailstorm in the passive microwave spectrum is conducted in order to characterize the vertical sources of radiation that contribute to the top-of-atmosphere microwave brightness temperatures (TB) which ...

Alberto Mugnai; Harry J. Cooper; Eric A. Smith; Gregory J. Tripoli

1990-01-01T23:59:59.000Z

455

Observational Analyses of North Atlantic Tropical Cyclones from NOAA Polar-Orbiting Satellite Microwave Data  

Science Conference Proceedings (OSTI)

Passive microwave observations from the current NOAA series of polar-orbiting satellites of a large sample of North Atlantic tropical cyclones are qualitatively and quantitatively analyzed. Microwave observations can penetrate the cloud cover ...

Christopher S. Velden

1989-01-01T23:59:59.000Z

456

False-Color Display of Special Sensor Microwave/Imager (SSM/I) Data  

Science Conference Proceedings (OSTI)

Displays of multi-frequency passive microwave data from the Special Sensor Microwave/Imager (SSM/I) flying on the Defense Meteorological Satellite Program (DMSP) spacecraft are presented. Observed brightness temperatures at 85.5 GHz (vertical and ...

Andrew J. Negri; Robert F. Adler; Christian D. Kummerow

1989-02-01T23:59:59.000Z

457

Passive Microwave Structure of Severe Tornadic Storms on 16 November 1987  

Science Conference Proceedings (OSTI)

Passive microwave observations using the Special Sensor Microwave/Imager are presented for severe tornadic storms in the lower midwestern United States on 16 November 1987. These measurements are compared with Geostationary Operational ...

Gerald M. Heymsfield; Richard Fulton

1994-11-01T23:59:59.000Z

458

A Method for Combined Passive?Active Microwave Retrievals of Cloud and Precipitation Profiles  

Science Conference Proceedings (OSTI)

Three-dimensional tropical squall-line simulations from the Goddard cumulus ensemble (GCE) model are used as input to radiative computations of upwelling microwave brightness temperatures and radar reflectivities at selected microwave sensor ...

William S. Olson; Christian D. Kummerow; Gerald M. Heymsfield; Louis Giglio

1996-10-01T23:59:59.000Z

459

Passive Microwave Observations of the Stratiform Regions of Two Tropical Oceanic Mesoscale Convective Systems  

Science Conference Proceedings (OSTI)

High-resolution passive microwave observations within the stratiform regions of two different tropical oceanic mesoscale convective systems are investigated in detail. The observations were obtained from the Advanced Microwave Precipitation ...

Gary McGaughey; Edward J. Zipser

1996-11-01T23:59:59.000Z

460

Combining Satellite Microwave Radiometer and Radar Observations to Estimate Atmospheric Heating Profiles  

Science Conference Proceedings (OSTI)

In this study, satellite passive microwave sensor observations from the Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI) are utilized to make estimates of latent + eddy sensible heating rates (Q1 ? QR) where Q1 is the apparent ...

Mircea Grecu; William S. Olson; Chung-Lin Shie; Tristan S. L’Ecuyer; Wei-Kuo Tao

2009-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "microwave background cmb" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

Improved Passive Microwave Retrievals of Rain Rate Over Land and Ocean. 2. Validation and Intercomparison  

Science Conference Proceedings (OSTI)

A new passive microwave rainfall retrieval algorithm for the Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI) has been developed that relies on a prior database derived from matchups between TMI brightness temperatures and ...

Grant W. Petty; Ke Li

462

On-orbit radiometric validation and field-of-view calibration of spaceborne microwave sounding instruments  

E-Print Network (OSTI)

Two calibration/validation efforts planned for current and future spaceborne microwave sounding instruments will be presented. First, the NPOESS Aircraft Sounder Testbed-Microwave (NAST-M) airborne sensor is used to directly ...

Blackwell, William J.

463

Aircraft Multifrequency Passive Microwave Observations of Light Precipitation over the Ocean  

Science Conference Proceedings (OSTI)

Aircraft passive microwave observations at 18, 37, 92, and 183 GHz of light oceanic precipitation are studied in conjunction with visible and infrared observations and ground-based radar data. Microwave signatures for clear, cloudy, and ...

Robert F. Adler; Ida M. Hakkarinen

1991-04-01T23:59:59.000Z

464

Relationships between Evaporative Fraction and Remotely Sensed Vegetation Index and Microwave Brightness Temperature for Semiarid Rangelands  

Science Conference Proceedings (OSTI)

Measurements of the microwave brightness temperature (TB) with the Pushbroom Microwave Radiometer (PBMR) over the Walnut Gulch Experimental Watershed were made on selected days during the MONSOON 90 field campaign. The PBMR is an L-band ...

W. P. Kustas; T. J. Schmugge; K. S. Humes; T. J. Jackson; R. Parry; M. A. Weltz; M. S. Moran

1993-12-01T23:59:59.000Z

465

Improved Passive Microwave Retrievals of Rain Rate over Land and Ocean. Part II: Validation and Intercomparison  

Science Conference Proceedings (OSTI)

A new passive microwave rainfall retrieval algorithm for the Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI) that relies on an a priori database derived from matchups between TMI brightness temperatures and precipitation radar (...

Grant W. Petty; Ke Li

2013-11-01T23:59:59.000Z

466

Microwave Radiative Transfer Studies Using Combined Multiparameter Radar and Radiometer Measurements during COHMEX  

Science Conference Proceedings (OSTI)

Theoretical calculations of the upwelling microwave radiances from clouds containing layers of rain, ice, and a melting region were performed at frequencies of 18, 37, and 92 GHz. These frequencies coincide with high-resolution microwave ...

J. Vivekanandan; J. Turk; G. L. Stephens; V. N. Bringi

1990-07-01T23:59:59.000Z

467

Correlations between Nimbus-7 Scanning Multichannel Microwave Radiometer Data and an Antecedent Precipitation Index  

Science Conference Proceedings (OSTI)

Passive microwave brightness temperatures from the Nimbus-7 Scanning Multichannel Microwave Radiometer (SMMR) can be used to infer the soil moisture content over agricultural areas such as the southern Great Plains of the United States. A linear ...

Gregory D. Wilke; Marshall J. McFarland

1986-02-01T23:59:59.000Z

468

A New Shipborne Microwave Refractometer for Estimating the Evaporation Flux at the Sea Surface  

Science Conference Proceedings (OSTI)

After a brief description of humidity measurement and a short presentation of methods of microwave refractometry for evaporation flux, a new X-band refractometer system is presented. Based on a new design and a new material for the microwave ...

J.-Y. Delahaye; C. Guerin; J. P. Vinson; H. Dupuis; A. Weill; H. Branger; L. Eymard; J. Lavergnat; G. Lachaud

2001-03-01T23:59:59.000Z

469

Intercalibrating Microwave Satellite Observations for Monitoring Long-Term Variations in Upper- and Midtropospheric Water Vapor  

Science Conference Proceedings (OSTI)

This paper analyzes the growing archive of 183-GHz water vapor absorption band measurements from the Advanced Microwave Sounding Unit B (AMSU-B) and Microwave Humidity Sounder (MHS) on board polar-orbiting satellites and document adjustments ...

Eui-Seok Chung; Brian J. Soden; Viju O. John

2013-10-01T23:59:59.000Z

470

Study of alpha background in a dark matter detector  

E-Print Network (OSTI)

Alpha background, specifically from radon and its progeny in the uranium and thorium chains, has been a major issue in dark matter detectors. This work focuses on alpha background presence in the DMTPC experiment by examining ...

Yegoryan, Hayk

2010-01-01T23:59:59.000Z

471

Passive background correction method for spatially resolved detection  

DOE Patents (OSTI)

A method for passive background correction during spatially or angularly resolved detection of emission that is based on the simultaneous acquisition of both the passive background spectrum and the spectrum of the target of interest.

Schmitt, Randal L. (Tijeras, NM); Hargis, Jr., Philip J. (Albuquerque, NM)

2011-05-10T23:59:59.000Z

472

Background division, a suitable technique for moving object detection  

Science Conference Proceedings (OSTI)

Nowadays, background model does not have any robust solution and constitutes one of the main problems in surveillance systems. Researchers are working in several approaches in order to get better background pixel models. This is a previous step to apply ...

Walter Izquierdo-Guerra; Edel García-Reyes

2010-11-01T23:59:59.000Z

473

Microwave Enhanced Rapid Solid State Synthesis of LiFePO4  

Science Conference Proceedings (OSTI)

New Saccharification Process of Cellulosic Biomass by Microwave Irradiation · Novel Lamination Method for Large Armor Panels · Raman Spectroscopy for ...

474

Microwave methods enable energy savings in restoration of highway pavements  

Science Conference Proceedings (OSTI)

Hot in place recycling of asphalt pavement by a method which utilizes microwave energy in combination with hot engine exhaust gases has been demonstrated to be technically and economically feasible. The process saves both energy and materials compared with conventional hot-mix recycling methods involving removal of old paving and reprocessing at hot-mix plants. Applications for microwave pavement heating include repair of cracks, joints between lanes and shoulders, wheel tracks, bridge decks, strip patching, and eventually in-place of full lanes of asphalt highways. The ability of microwave energy to heat pavements rapidly and fairly uniformly to depths of up to 6 inches make this new method uniquely suitable for repair and restoration of bridges, roads and highways, and also for the construction of new paved roads in places where hot-mix plants are not available.

Jeppson, M.R.; Smith, F.J.

1983-08-01T23:59:59.000Z

475

Microwave methods enable energy savings in restoration of highway pavements  

Science Conference Proceedings (OSTI)

Hot in-place recycling of asphalt pavement by a method which utilizes microwave energy in combination with hot-engine exhaust gases has been demonstrated to be technically and economically feasible. The process saves both energy and materials compared with conventional hot-mix recycling methods involving removal of old paving and reprocessing at hot-mix plants. Applications for microwave pavement heating include repair of cracks, joints between lanes and shoulders, wheel tracks, bridge decks, strip patching, and eventually in-place recycling of full lanes of asphalt highways. The ability of microwave energy to heat pavements rapidly and fairly uniformly to depths of up to 6 inches make this new method uniquely suitable for repair and restoration of bridges, roads and highways, and also for the construction of new paved roads in places where hot-mix plants are not available.

Jeppson, M.R.; Smith, F.J.

1983-01-01T23:59:59.000Z

476

One piece microwave container screens for electrodeless lamps  

DOE Patents (OSTI)

A microwave powered electrodeless lamp includes an improved screen unit having mesh and solid sections with an internal reflector to reflect light into a light-transmitting chamber defined in the lamp microwave cavity by the reflector and the mesh section. A discharge envelope of a bulb is disposed in the light-transmitting chamber. Light emitted from the envelope is prevented by the reflector from entering the cavity portion bounded by the solid section of the screen. Replacing mesh material by solid metal material as part of the screen unit significantly reduces leakage of microwave energy from the lamp. The solid section has multiple compliant fingers defined therein for engaging the periphery of a flange on the waveguide unit so that a hose clamp can easily secure the screen to the assembly. Screen units of this type having different mesh section configurations can be interchanged in the lamp assembly to produce different respective illumination patterns.

Turner, Brian (Myersville, MD); Ury, Michael (Bethesda, MD)

1998-01-01T23:59:59.000Z

477

Microwave-Induced Chemical Synthesis Initiative Strategic Research 1994-1997  

Science Conference Proceedings (OSTI)

The Microwave-Induced Chemical Synthesis Initiative focuses on the questions and opportunities associated with the effect of microwaves on chemical reactions, particularly catalytic reactions. This compendium of report and conclusions from the initiative contains a variety of new findings, including the results of seven research programs and two microwave conferences.

1998-06-29T23:59:59.000Z

478

Microwave tomography for breast cancer detection on Cell broadband engine processors  

Science Conference Proceedings (OSTI)

Microwave tomography (MT) is a safe screening modality that can be used for breast cancer detection. The technique uses the dielectric property contrasts between different breast tissues at microwave frequencies to determine the existence of abnormalities. ... Keywords: Breast cancer detection, Cell BE processor, Finite-difference time-domain (FDTD), Microwave tomography (MT)

Meilian Xu; Parimala Thulasiraman; Sima Noghanian

2012-09-01T23:59:59.000Z

479

Apparatus with moderating material for microwave heat treatment of manufactured components  

DOE Patents (OSTI)

An apparatus for heat treating manufactured components using microwave energy and microwave susceptor material. Heat treating medium such as eutectic salts may be employed. A fluidized bed introduces process gases which may include carburizing or nitriding gases The process may be operated in a batch mode or continuous process mode. A microwave heating probe may be used to restart a frozen eutectic salt bath.

Ripley, Edward B. (Knoxville, TN)

2011-05-10T23:59:59.000Z

480

Role of Background in the CERCLA Cleanup Program  

NLE Websites -- All DOE Office Websites (Extended Search)

Background in the CERCLA Cleanup Program Background in the CERCLA Cleanup Program U.S. Environmental Protection Agency Office of Solid Waste and Emergency Response Office of Emergency and Remedial Response April 26, 2002 OSWER 9285.6-07P OSWER 9285.6-07P page 2 of 13 Table of Contents Purpose . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 3 of 13 History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 4 of 13 Definitions of Terms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 5 of 13 Consideration of Background in Risk Assessment . . . . . . . . . . . . . . . . . . . . . . . . . . Page 6 of 13 Consideration of Background in Risk Management . . . . . . . . . . . . . . . . . . . . . . . . . Page 7 of 13 Consideration of Background in Risk Communication . . . . . . . . . . . . . . . . . . . . . . . Page 8 of 13 Hypothetical Case Examples .

Note: This page contains sample records for the topic "microwave background cmb" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


481

Microwave whispering gallery resonator for efficient optical up-conversion  

E-Print Network (OSTI)

Conversion of microwave radiation into the optical range has been predicted to reach unity quantum efficiency in whispering gallery resonators made from an optically nonlinear crystal and supporting microwave and optical modes simultaneously. In this work we theoretically explore and experimentally demonstrate a resonator geometry that can provide the required phase matching for such a conversion at any desired frequency in the sub-THz range. We show that such a ring-shaped resonator not only allows for the phase matching, but also maximizes the overlap of the interacting fields. As a result, unity-efficient conversion is expected in a resonator with feasible parameters.

D. V. Strekalov; H. G. L. Schwefel; A. A. Savchenkov; A. B. Matsko; L. J. Wang; N. Yu

2009-05-18T23:59:59.000Z

482

Ultra high vacuum broad band high power microwave window  

DOE Patents (OSTI)

An improved high vacuum microwave window has been developed that utilizes high density polyethylene coated on two sides with SiOx, SiNx, or a combination of the two. The resultant low dielectric and low loss tangent window creates a low outgassing, low permeation seal through which broad band, high power microwave energy may be passed. No matching device is necessary and the sealing technique is simple. The features of the window are broad band transmission, ultra-high vacuum compatibility with a simple sealing technique, low voltage standing wave ratio, high power transmission and low cost.

Nguyen-Tuong, Viet (Seaford, VA); Dylla, III, Henry Frederick (Yorktown, VA)

1997-01-01T23:59:59.000Z

483

Ultra high vacuum broad band high power microwave window  

DOE Patents (OSTI)

An improved high vacuum microwave window has been developed that utilizes high density polyethylene coated on two sides with SiOx, SiNx, or a combination of the two. The resultant low dielectric and low loss tangent window creates a low outgassing, low permeation seal through which broad band, high power microwave energy may be passed. No matching device is necessary and the sealing technique is simple. The features of the window are broad band transmission, ultra-high vacuum compatibility with a simple sealing technique, low voltage standing wave ratio, high power transmission and low cost. 5 figs.

Nguyen-Tuong, V.; Dylla, H.F. III

1997-11-04T23:59:59.000Z

484

Apparatus for mounting a diode in a microwave circuit  

DOE Patents (OSTI)

Apparatus for mounting a diode in a microwave circuit for making electrical contact between the circuit and ground and for dissipation of heat between the diode and a heat sink. The diode, supported on a thermally and electrically conductive member, is resiliently pressed in electrical contact with the microwave circuit. A tapered collar on the member is elastically deformably wedged into a tapered aperture formed in a heat sink. The wedged collar tightens firmly around the member establishing good thermal and electrical conduction from the diode to the heat sink and ground. Disassembly is facilitated because of the elastically deformed collar.

Liu, Shing-gong (Princeton, NJ)

1976-07-27T23:59:59.000Z

485

Microwave heating effect on the dog thyroid gland  

SciTech Connect

Dog thyroid glands were exposed in vivo to 2450 MHz, CW microwave fields for 2 h using a dielectrically loaded waveguide applicator. Specific absorption rates of 58, 131, and 190 W/kg in the center of the thyroid gland resulted in temperatures of 38 to 39/sup 0/C, 40 to 42/sup 0/C, and 44 to 46/sup 0/C, respectively. An increase in the heated gland's thyroid hormone, thyroxine (T4) and triiodothyronine (T3), release rate was observed. This result demonstrates that the dog thyroid gland can be directly stimulated by microwave heating.

Magin, R.L.; Lu, S.T.; Michaelson, S.M.

1977-11-01T23:59:59.000Z

486

A high spatial resolution analysis of the MAXIMA-1 cosmicmicrowave background anisotropy data  

SciTech Connect

We extend the analysis of the MAXIMA-1 cosmic microwave background data to smaller angular scales. MAXIMA, a bolometric balloon-borne experiment, mapped a 124 deg(2) region of the sky with 10 minutes resolution at frequencies of 150, 240, and 410 GHz during its first flight. The original analysis, which covered the multipole range 36 less than or equal to l less than or equal to 785 using a 100 deg(2) map, is extended to l = 1235 using a subset of the data from three 150 GHz photometers in the fully cross-linked central 60 deg(2) of the map. The main improvement over the original analysis is the use of 3 minutes square pixels in the calculation of the map. The new analysis is consistent with the original for l<785. For l>785, where inflationary models predict a third acoustic peak, the new analysis shows power with an amplitude of 56 +/- 7 muK at l similar or equal to 850 in excess to the average power of 42 +/- 3 muK in the range 441

Lee, A.T.; Ade, P.; Balbi, A.; Bock, J.; Borrill, J.; Boscaleri,A.; de Bernardis, P.; Ferreira P.G.; Hanany, S.; Hristov, V.V.; Jaffe,A.H.; Mauskopf, P.D.; Netterfield, C.B.; Pascale, E.; Rabii, B.; Richards, P.L.; Smoot, G.F.; Stompor, R.; Winant, C.D.; Wu, J.H.P.

2001-04-29T23:59:59.000Z

487

Biographical Sketch-CMB2013  

Science Conference Proceedings (OSTI)

... (3) Selective Adsorption of Ethylene over Ethane and Propylene over Propane in the Metal-Organic Frameworks M2(dobdc) (M = Mg, Mn, Fe, Co, Ni ...

2013-04-19T23:59:59.000Z

488

After the Big Bang  

NLE Websites -- All DOE Office Websites (Extended Search)

After the Big Bang After the Big Bang Golden Age of Cosmology Big Bang Timeline Big Bang? Standard Big Bang Cosmology Slide 6 Big Bang Nucleosynthesis Redshift and Doppler Shift Doppler Shift Cepheid variables and Nebulae Standard Candles Hubble Expansion Hubble Law Cosmic Microwave Background Cosmic Background Explorer (1989-1993) COBE data/DMR CMB Fluctuations What is inflation? Why believe in inflation? Horizon Problem No inflation With inflation Flatness Problem Slide 24 Wilkinson Microwave Anisotropy Probe (2001-present) Fluctuations and geometry Universe's Baby Pictures Compare to COBE CMB vs. Inflation WMAP angular power spectrum Dark Matter Galaxy Rotation Curves Hot gas in Galaxy Clusters Dark Matter Halo Old view: Density of the Universe determines its destiny Hubble Expansion revisited

489

Microwave Treatment as a Pesticide Alternative for Stored-Products  

SciTech Connect

This CRADA was a continuation of earlier work with Micro-Grain, Inc. to develop power, high frequency microwave treatment process to treat insect infested grain. ORNLs role was as a subcontractor to Micro-Grain's Phase II SBIR project funded by the US Department of Agriculture. The primary objective was to develop a commercial scale prototype unit capable of treating infested grain at flow rates approaching 1 kg/sec, which is required to be viable in the grain handling industry. A flow rate of {approx} 0.12 Kg/second was demonstrated at 20 kW microwave power level with 100% kill rate. The system is capable of 200 kW however waveguide arcing due to grain dust in the waveguide limited the power to 20 kW during the tests. Development tasks performed during the project included modification of an existing high-power microwave exposure facility to uniformly process large grain samples at high flow rates and improved instrumentation to detect grain flow and uniformity. Microwave processing tasks include a series of controlled exposure tests using infested grain samples provided and analyzed by the University of Oklahoma. Grain samples were infested with red flour beetles which proved the most difficult to kill in earlier tests. Most of the samples processed resulted in quite successful kill rates and a maximum grain temperature of 46 C. The facilities utilized at ORNL are located in the Fusion Energy building (9201-2 at Y-12) and include the 28 GHz 200 kW CW high power microwave facility and microwave test equipment associated with the FED Microwave Development Laboratory in 9201-2. An improved microwave exposure chamber and grain flow control and handling equipment were designed and build as a joint effort between Micro-Grain and ORNL. A number of insect infested grain tests were successfully performed although the higher power, higher flow rates were limited by arcing in the microwave waveguide and damage to the gyrotron output window. Test results and the overall performance of the applicator system are very favorable for continued development of the concept. Further tests were performed in a large high power 2.45 GHz microwave applicator in batches. These samples were also quite effectively treated which supports the concept that a lower cost, lower frequency microwave system might be more successful due to the improved economics and simpler operation and maintenance of the low frequency system. Follow-on work is still possible however the untimely death of Steve Halverson, founder of Micro-grain, has essentially brought the development work to a close for now. Micro-Grain is being run by relatives at a low level who are not actively pursuing further funding.

Bigelow, T.S.; Forrester, S.C.; Halverson, S.; Halverson, B.; Phillips, T.

2003-05-21T23:59:59.000Z

490

CORRELATIONS IN THE (SUB)MILLIMETER BACKGROUND FROM ACT Multiplication-Sign BLAST  

Science Conference Proceedings (OSTI)

We present measurements of the auto- and cross-frequency correlation power spectra of the cosmic (sub)millimeter background at 250, 350, and 500 {mu}m (1200, 860, and 600 GHz) from observations made with the Balloon-borne Large Aperture Submillimeter Telescope (BLAST); and at 1380 and 2030 {mu}m (218 and 148 GHz) from observations made with the Atacama Cosmology Telescope (ACT). The overlapping observations cover 8.6 deg{sup 2} in an area relatively free of Galactic dust near the south ecliptic pole. The ACT bands are sensitive to radiation from the cosmic microwave background, to the Sunyaev-Zel'dovich effect from galaxy clusters, and to emission by radio and dusty star-forming galaxies (DSFGs), while the dominant contribution to the BLAST bands is from DSFGs. We confirm and extend the BLAST analysis of clustering with an independent pipeline and also detect correlations between the ACT and BLAST maps at over 25{sigma} significance, which we interpret as a detection of the DSFGs in the ACT maps. In addition to a Poisson component in the cross-frequency power spectra, we detect a clustered signal at 4{sigma}, and using a model for the DSFG evolution and number counts, we successfully fit all of our spectra with a linear clustering model and a bias that depends only on redshift and not on scale. Finally, the data are compared to, and generally agree with, phenomenological models for the DSFG population. This study demonstrates the constraining power of the cross-frequency correlation technique to constrain models for the DSFGs. Similar analyses with more data will impose tight constraints on future models.

Hajian, Amir; Battaglia, Nick; Bond, J. Richard [Canadian Institute for Theoretical Astrophysics, University of Toronto, Toronto, ON M5S 3H8 (Canada); Viero, Marco P.; Bock, James J. [California Institute of Technology, Pasadena, CA 91125 (United States); Addison, Graeme [Department of Astrophysics, Oxford University, Oxford, OX1 3RH (United Kingdom); Aguirre, Paula [Departamento de Astronomia y Astrofisica, Facultad de Fisica, Pontificia Universidad Catolica, Casilla 306, Santiago 22 (Chile); Appel, John William; Duenner, Rolando; Essinger-Hileman, Thomas; Fowler, Joseph W.; Hincks, Adam D. [Joseph Henry Laboratories of Physics, Jadwin Hall, Princeton University, Princeton, NJ 08544 (United States); Das, Sudeep; Dunkley, Joanna [Department of Astrophysical Sciences, Peyton Hall, Princeton University, Princeton, NJ 08544 (United States); Devlin, Mark J.; Dicker, Simon R. [Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA 19104 (United States); Hughes, John P. [Department of Physics and Astronomy, Rutgers, State University of New Jersey, Piscataway, NJ 08854-8019 (United States); Halpern, Mark [Department of Physics and Astronomy, University of British Columbia, Vancouver, BC V6T 1Z4 (Canada); Hasselfield, Matthew [Laboratoire APC, Universite Paris Diderot, 75205 Paris (France); Hilton, Matt [Astrophysics and Cosmology Research Unit, School of Mathematical Sciences, University of KwaZulu-Natal, Durban 4041 (South Africa); and others

2012-01-01T23:59:59.000Z