Exploring Quantum Gravity with Very-High-Energy Gamma-Ray Instruments - Prospects and Limitations
Wagner, Robert
2009-04-08
Some models for quantum gravity (QG) violate Lorentz invariance and predict an energy dependence of the speed of light, leading to a dispersion of high-energy gamma-ray signals that travel over cosmological distances. Limits on the dispersion from short-duration substructures observed in gamma-rays emitted by gamma-ray bursts (GRBs) at cosmological distances have provided interesting bounds on Lorentz invariance violation (LIV). Recent observations of unprecedentedly fast flares in the very-high energy gamma-ray emission of the active galactic nuclei (AGNs) Mkn 501 in 2005 and PKS 2155-304 in 2006 resulted in the most constraining limits on LIV from light-travel observations, approaching the Planck mass scale, at which QG effects are assumed to become important. I review the current status of LIV searches using GRBs and AGN flare events, and discuss limitations of light-travel time analyses and prospects for future instruments in the gamma-ray domain.
Oji, L. N.
2015-10-01
August 2015, scale solids from the 16H Evaporator Gravity Drain Line (GDL) to the Tank 38H were delivered to SRNL for analysis. The desired analytical goal was to identify and confirm the crystalline structure of the scale material and determine if the form of the aluminosilicate mineral was consistent with previous analysis of the scale material from the GDL.
Is nonrelativistic gravity possible?
Kocharyan, A. A.
2009-07-15
We study nonrelativistic gravity using the Hamiltonian formalism. For the dynamics of general relativity (relativistic gravity) the formalism is well known and called the Arnowitt-Deser-Misner (ADM) formalism. We show that if the lapse function is constrained correctly, then nonrelativistic gravity is described by a consistent Hamiltonian system. Surprisingly, nonrelativistic gravity can have solutions identical to relativistic gravity ones. In particular, (anti-)de Sitter black holes of Einstein gravity and IR limit of Horava gravity are locally identical.
Alexandre, Jean; Pasipoularides, Pavlos
2011-10-15
In this note we examine whether spherically symmetric solutions in covariant Horava-Lifshitz gravity can reproduce Newton's Law in the IR limit {lambda}{yields}1. We adopt the position that the auxiliary field A is independent of the space-time metric [J. Alexandre and P. Pasipoularides, Phys. Rev. D 83, 084030 (2011).][J. Greenwald, V. H. Satheeshkumar, and A. Wang, J. Cosmol. Astropart. Phys. 12 (2010) 007.], and we assume, as in [A. M. da Silva, Classical Quantum Gravity 28, 055011 (2011).], that {lambda} is a running coupling constant. We show that under these assumptions, spherically symmetric solutions fail to restore the standard Newtonian physics in the IR limit {lambda}{yields}1, unless {lambda} does not run, and has the fixed value {lambda}=1. Finally, we comment on the Horava and Melby-Thompson approach [P. Horava and C. M. Melby-Thompson, Phys. Rev. D 82, 064027 (2010).] in which A is assumed as a part of the space-time metric in the IR.
Cohen, S.A.; Hosea, J.C.; Timberlake, J.R.
1984-10-19
A limiter with a specially contoured front face is provided. The front face of the limiter (the plasma-side face) is flat with a central indentation. In addition, the limiter shape is cylindrically symmetric so that the limiter can be rotated for greater heat distribution. This limiter shape accommodates the various power scrape-off distances lambda p, which depend on the parallel velocity, V/sub parallel/, of the impacting particles.
Cohen, Samuel A.; Hosea, Joel C.; Timberlake, John R.
1986-01-01
A limiter with a specially contoured front face accommodates the various power scrape-off distances .lambda..sub.p, which depend on the parallel velocity, V.sub..parallel., of the impacting particles. The front face of the limiter (the plasma-side face) is flat with a central indentation. In addition, the limiter shape is cylindrically symmetric so that the limiter can be rotated for greater heat distribution.
Oz, E.; Myers, C. E.; Yamada, M.; Ji, H.; Kulsrud, R. M.; Xie, J.
2011-07-19
The stability properties of partial toroidal flux ropes are studied in detail in the laboratory, motivated by ubiquitous arched magnetic structures found on the solar surface. The flux ropes studied here are magnetized arc discharges formed between two electrodes in the Magnetic Reconnection Experiment (MRX) [Yamada et al., Phys. Plasmas, 4, 1936 (1997)]. The three dimensional evolution of these flux ropes is monitored by a fast visible light framing camera, while their magnetic structure is measured by a variety of internal magnetic probes. The flux ropes are consistently observed to undergo large-scale oscillations as a result of an external kink instability. Using detailed scans of the plasma current, the guide field strength, and the length of the flux rope, we show that the threshold for kink stability is governed by the Kruskal-Shafranov limit for a flux rope that is held fixed at both ends (i.e., qa = 1).
Limits on Variations in Fundamental Constants from 21-cm and Ultraviolet Quasar Absorption Lines
Tzanavaris, P.; Webb, J.K.; Flambaum, V.V.; Curran, S.J.; Murphy, M.T.
2005-07-22
Quasar absorption spectra at 21-cm and UV rest wavelengths are used to estimate the time variation of x{identical_to}{alpha}{sup 2}g{sub p}{mu}, where {alpha} is the fine structure constant, g{sub p} the proton g factor, and m{sub e}/m{sub p}{identical_to}{mu} the electron/proton mass ratio. Over a redshift range 0.24 < or approx. z{sub abs} < or approx. 2.04, <{delta}x/x>{sub total}{sup weighted}=(1.17{+-}1.01)x10{sup -5}. A linear fit gives x/x=(-1.43{+-}1.27)x10{sup -15} yr{sup -1}. Two previous results on varying {alpha} yield the strong limits {delta}{mu}/{mu}=(2.31{+-}1.03)x10{sup -5} and {delta}{mu}/{mu}=(1.29{+-}1.01)x10{sup -5}. Our sample, 8x larger than any previous, provides the first direct estimate of the intrinsic 21-cm and UV velocity differences {approx}6 km s{sup -1}.
Lujan, Richard E.
2001-01-01
A mechanical gravity brake that prevents hoisted loads within a shaft from free-falling when a loss of hoisting force occurs. A loss of hoist lifting force may occur in a number of situations, for example if a hoist cable were to break, the brakes were to fail on a winch, or the hoist mechanism itself were to fail. Under normal hoisting conditions, the gravity brake of the invention is subject to an upward lifting force from the hoist and a downward pulling force from a suspended load. If the lifting force should suddenly cease, the loss of differential forces on the gravity brake in free-fall is translated to extend a set of brakes against the walls of the shaft to stop the free fall descent of the gravity brake and attached load.
Davis, Hyman R.; Long, R. H.; Simone, A. A.
1979-01-01
Solids are separated from a liquid in a gravity settler provided with inclined solid intercepting surfaces to intercept the solid settling path to coalesce the solids and increase the settling rate. The intercepting surfaces are inverted V-shaped plates, each formed from first and second downwardly inclined upwardly curved intersecting conical sections having their apices at the vessel wall.
Born-Infeld gravity in three dimensions
Alishahiha, Mohsen; Naseh, Ali; Soltanpanahi, Hesam
2010-07-15
In this paper we explore different aspects of three dimensional Born-Infeld as well as Born-Infeld-Chern-Simons gravity. We show that the models have anti-de Sitter and anti-de Sitter wave vacuum solutions. Moreover, we observe that although Born-Infeld-Chern-Simons gravity admits a logarithmic solution, Born-Infeld gravity does not, though it has a limiting logarithmic solution as we approach the critical point.
Energy Information Administration (EIA) (indexed site)
gravity of 22 degrees or below. Intermediate crudes fall in the range of 22 degrees to 38 degrees API gravity. ASTM: American Society for Testing and Materials. Aviation...
Gravity Data for west-central Colorado
Zehner, Richard
2012-04-06
Modeled Bouger Gravity data was extracted from the Pan American Center for Earth and Environmental Studies Gravity Database of the U.S. at http://irpsrvgis08.utep.edu/viewers/Flex/GravityMagnetic/GravityMagnetic_CyberShare/ on 2/29/2012. The downloaded text file was opened in an Excel spreadsheet. This spreadsheet data was then converted into an ESRI point shapefile in UTM Zone 13 NAD27 projection, showing location and gravity (in milligals). This data was then converted to grid and then contoured using ESRI Spatial Analyst. This dataset contains the original spreadsheet data, a point shapefile showing gravity station locations and Bouger gravity, and a line shapefile showing 1 milligal contours. Projection: UTM Zone 13 NAD27 Gravity Contour Shapefile Extent: West -108.366690 East -105.478730 North 40.932318 South 36.961606 Gravity Point Shapefile Extent: West -108.366692 East -105.478847 North 40.932361 South 36.961606 Data from From University of Texas: Pan American Center for Earth and Environmental Studies
Massive gravity on de Sitter and unique candidate for partially massless gravity
Rham, Claudia de; Renaux-Petel, Sébastien E-mail: srenaux@lpthe.jussieu.fr
2013-01-01
We derive the decoupling limit of Massive Gravity on de Sitter in an arbitrary number of space-time dimensions d. By embedding d-dimensional de Sitter into d+1-dimensional Minkowski, we extract the physical helicity-1 and helicity-0 polarizations of the graviton. The resulting decoupling theory is similar to that obtained around Minkowski. We take great care at exploring the partially massless limit and define the unique fully non-linear candidate theory that is free of the helicity-0 mode in the decoupling limit, and which therefore propagates only four degrees of freedom in four dimensions. In the latter situation, we show that a new Vainshtein mechanism is at work in the limit m{sup 2} ? 2H{sup 2} which decouples the helicity-0 mode when the parameters are different from that of partially massless gravity. As a result, there is no discontinuity between massive gravity and its partially massless limit, just in the same way as there is no discontinuity in the massless limit of massive gravity. The usual bounds on the graviton mass could therefore equivalently well be interpreted as bounds on m{sup 2}?2H{sup 2}. When dealing with the exact partially massless parameters, on the other hand, the symmetry at m{sup 2} = 2H{sup 2} imposes a specific constraint on matter. As a result the helicity-0 mode decouples without even the need of any Vainshtein mechanism.
Quantum gravity effects in the Kerr spacetime
Reuter, M.; Tuiran, E.
2011-02-15
We analyze the impact of the leading quantum gravity effects on the properties of black holes with nonzero angular momentum by performing a suitable renormalization group improvement of the classical Kerr metric within quantum Einstein gravity. In particular, we explore the structure of the horizons, the ergosphere, and the static limit surfaces as well as the phase space available for the Penrose process. The positivity properties of the effective vacuum energy-momentum tensor are also discussed and the 'dressing' of the black hole's mass and angular momentum are investigated by computing the corresponding Komar integrals. The pertinent Smarr formula turns out to retain its classical form. As for their thermodynamical properties, a modified first law of black-hole thermodynamics is found to be satisfied by the improved black holes (to second order in the angular momentum); the corresponding Bekenstein-Hawking temperature is not proportional to the surface gravity.
Polchinski, Joseph [Kavli Institute for Theoretical Physics
2010-09-01
Gauge theories, which describe the particle interactions, are well understood, while quantum gravity leads to many puzzles. Remarkably, in recent years we have learned that these are actually dual, the same system written in different variables. On the one hand, this provides our most precise description of quantum gravity, resolves some long-standing paradoxes, and points to new principles. On the other, it gives a new perspective on strong interactions, with surprising connections to other areas of physics. I describe these ideas, and discuss current and future directions.
Nicole Lautze
2015-12-15
Gravity model for the state of Hawaii. Data is from the following source: Flinders, A.F., Ito, G., Garcia, M.O., Sinton, J.M., Kauahikaua, J.P., and Taylor, B., 2013, Intrusive dike complexes, cumulate cores, and the extrusive growth of Hawaiian volcanoes: Geophysical Research Letters, v. 40, p. 3367â€“3373, doi:10.1002/grl.50633.
Kane, M.F.; Webring, M.W.; Bhattacharyya, B.K.
1981-12-31
Recent (1977 to 1978) gravity and aeromagnetic surveys of the Timber Mountain region, southern Nevada, have revealed new details of subsurface structure and lithology. The data strongly suggest that deformation caused by volcanic events has been accommodated along straight-line faults combining in such a fashion as to given a curvilinear appearance to regional structure. The magnetic data suggest that rock units in the central graben and along the southeast margin of Timber Mountain may have been altered, perhaps thermally, from their original state. The gravity data indicate that the south part of the Timber Mountain is underlain by relatively dense rock possibly intrusive rock, like that which crops out along its southeast side. The gravity data also suggest that the Silent Canyon caldera may extend considerably south of its presently indicated southern limit and may underlie much of the area of Timber Mountain. The moat areas appear to be more rectangular or triangular than annular in shape. The southern part of Timber Mountain caldera is separated from the Yucca Mountain area to the south by a triangular horst. The structural relations of the rock units making up the horst are complex. Several linear terrain features in the southern part of the caldera area are closely aligned with geophysical features, implying that the terrain features are fault-controlled.
Hainline, Kevin N.; Hickox, Ryan C.; Greene, Jenny E.; Myers, Adam D.; Zakamska, Nadia L.; Liu, Guilin; Liu, Xin
2014-05-20
We examine the spatial extent of the narrow-line regions (NLRs) of a sample of 30 luminous obscured quasars at 0.4 < z < 0.7 observed with spatially resolved Gemini-N GMOS long-slit spectroscopy. Using the [O III] ?5007 emission feature, we estimate the size of the NLR using a cosmology-independent measurement: the radius where the surface brightness falls to 10{sup –15} erg s{sup –1} cm{sup –2} arcsec{sup –2}. We then explore the effects of atmospheric seeing on NLR size measurements and conclude that direct measurements of the NLR size from observed profiles are too large by 0.1-0.2 dex on average, as compared to measurements made to best-fit Sérsic or Voigt profiles convolved with the seeing. These data, which span a full order of magnitude in IR luminosity (log (L {sub 8} {sub ?m}/erg s{sup –1}) = 44.4-45.4), also provide strong evidence that there is a flattening of the relationship between NLR size and active galactic nucleus luminosity at a seeing-corrected size of ?7 kpc. The objects in this sample have high luminosities which place them in a previously under-explored portion of the size-luminosity relationship. These results support the existence of a maximal size of the NLR around luminous quasars; beyond this size, there is either not enough gas or the gas is over-ionized and does not produce enough [O III] ?5007 emission.
Prost, Lionel Robert
2007-02-14
The High Current Experiment (HCX) at Lawrence Berkeley National Laboratory is part of the US program that explores heavy-ion beam as the driver option for fusion energy production in an Inertial Fusion Energy (IFE) plant. The HCX is a beam transport experiment at a scale representative of the low-energy end of an induction linear accelerator driver. The primary mission of this experiment is to investigate aperture fill factors acceptable for the transport of space-charge-dominated heavy-ion beams at high intensity (line charge density {approx}0.2 {micro}C/m) over long pulse durations (4 {micro}s) in alternating gradient focusing lattices of electrostatic or magnetic quadrupoles. This experiment is testing transport issues resulting from nonlinear space-charge effects and collective modes, beam centroid alignment and steering, envelope matching, image charges and focusing field nonlinearities, halo and, electron and gas cloud effects. We present the results for a coasting 1 MeV K{sup +} ion beam transported through ten electrostatic quadrupoles. The measurements cover two different fill factor studies (60% and 80% of the clear aperture radius) for which the transverse phase-space of the beam was characterized in detail, along with beam energy measurements and the first halo measurements. Electrostatic quadrupole transport at high beam fill factor ({approx}80%) is achieved with acceptable emittance growth and beam loss. We achieved good envelope control, and re-matching may only be needed every ten lattice periods (at 80% fill factor) in a longer lattice of similar design. We also show that understanding and controlling the time dependence of the envelope parameters is critical to achieving high fill factors, notably because of the injector and matching section dynamics.
Geometric scalar theory of gravity
Novello, M.; Bittencourt, E.; Goulart, E.; Salim, J.M.; Toniato, J.D.; Moschella, U. E-mail: eduhsb@cbpf.br E-mail: egoulart@cbpf.br E-mail: toniato@cbpf.br
2013-06-01
We present a geometric scalar theory of gravity. Our proposal will be described using the ''background field method'' introduced by Gupta, Feynman, Deser and others as a field theory formulation of general relativity. We analyze previous criticisms against scalar gravity and show how the present proposal avoids these difficulties. This concerns not only the theoretical complaints but also those related to observations. In particular, we show that the widespread belief of the conjecture that the source of scalar gravity must be the trace of the energy-momentum tensor — which is one of the main difficulties to couple gravity with electromagnetic phenomenon in previous models — does not apply to our geometric scalar theory. From the very beginning this is not a special relativistic scalar gravity. The adjective ''geometric'' pinpoints its similarity with general relativity: this is a metric theory of gravity. Some consequences of this new scalar theory are explored.
Cosmology in general massive gravity theories
Comelli, D.; Nesti, F.; Pilo, L. E-mail: fabrizio.nesti@aquila.infn.it
2014-05-01
We study the cosmological FRW flat solutions generated in general massive gravity theories. Such a model are obtained adding to the Einstein General Relativity action a peculiar non derivative potentials, function of the metric components, that induce the propagation of five gravitational degrees of freedom. This large class of theories includes both the case with a residual Lorentz invariance as well as the case with rotational invariance only. It turns out that the Lorentz-breaking case is selected as the only possibility. Moreover it turns out that that perturbations around strict Minkowski or dS space are strongly coupled. The upshot is that even though dark energy can be simply accounted by massive gravity modifications, its equation of state w{sub eff} has to deviate from -1. Indeed, there is an explicit relation between the strong coupling scale of perturbations and the deviation of w{sub eff} from -1. Taking into account current limits on w{sub eff} and submillimiter tests of the Newton's law as a limit on the possible strong coupling scale, we find that it is still possible to have a weakly coupled theory in a quasi dS background. Future experimental improvements on short distance tests of the Newton's law may be used to tighten the deviation of w{sub eff} form -1 in a weakly coupled massive gravity theory.
Gravity Techniques | Open Energy Information
OpenEI (Open Energy Information) [EERE & EIA]
in density, such as at fault contacts. 2 Gravity techniques are also applied towards reservoir monitoring for subsidence and mass gain or loss within a geothermal reservoir...
Gravity Methods | Open Energy Information
OpenEI (Open Energy Information) [EERE & EIA]
Methods Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Gravity Methods Details Activities (0) Areas (0) Regions (0) NEPA(3) Exploration...
NUT-charged black holes in Gauss-Bonnet gravity
Dehghani, M.H.; Mann, R.B.
2005-12-15
We investigate the existence of Taub-NUT (Newman-Unti-Tamburino) and Taub-bolt solutions in Gauss-Bonnet gravity and obtain the general form of these solutions in d dimensions. We find that for all nonextremal NUT solutions of Einstein gravity having no curvature singularity at r=N, there exist NUT solutions in Gauss-Bonnet gravity that contain these solutions in the limit that the Gauss-Bonnet parameter {alpha} goes to zero. Furthermore there are no NUT solutions in Gauss-Bonnet gravity that yield nonextremal NUT solutions to Einstein gravity having a curvature singularity at r=N in the limit {alpha}{yields}0. Indeed, we have nonextreme NUT solutions in 2+2k dimensions with nontrivial fibration only when the 2k-dimensional base space is chosen to be CP{sup 2k}. We also find that the Gauss-Bonnet gravity has extremal NUT solutions whenever the base space is a product of 2-torii with at most a two-dimensional factor space of positive curvature. Indeed, when the base space has at most one positively curved two-dimensional space as one of its factor spaces, then Gauss-Bonnet gravity admits extreme NUT solutions, even though there a curvature singularity exists at r=N. We also find that one can have bolt solutions in Gauss-Bonnet gravity with any base space with factor spaces of zero or positive constant curvature. The only case for which one does not have bolt solutions is in the absence of a cosmological term with zero curvature base space.
Perturbations of nested branes with induced gravity
Sbisŕ, Fulvio; Koyama, Kazuya E-mail: kazuya.koyama@port.ac.uk
2014-06-01
We study the behaviour of weak gravitational fields in models where a 4D brane is embedded inside a 5D brane equipped with induced gravity, which in turn is embedded in a 6D spacetime. We consider a specific regularization of the branes internal structures where the 5D brane can be considered thin with respect to the 4D one. We find exact solutions corresponding to pure tension source configurations on the thick 4D brane, and study perturbations at first order around these background solutions. To perform the perturbative analysis, we adopt a bulk-based approach and we express the equations in terms of gauge invariant and master variables using a 4D scalar-vector-tensor decomposition. We then propose an ansatz on the behaviour of the perturbation fields when the thickness of the 4D brane goes to zero, which corresponds to configurations where gravity remains finite everywhere in the thin limit of the 4D brane. We study the equations of motion using this ansatz, and show that they give rise to a consistent set of differential equations in the thin limit, from which the details of the internal structure of the 4D brane disappear. We conclude that the thin limit of the ''ribbon'' 4D brane inside the (already thin) 5D brane is well defined (at least when considering first order perturbations around pure tension configurations), and that the gravitational field on the 4D brane remains finite in the thin limit. We comment on the crucial role of the induced gravity term on the 5D brane.
Geologic interpretation of gravity anomalies
Andreyev, B.A.; Klushin, I.G.
1990-04-19
This Russian textbook provides a sufficiently complete and systematic illumination of physico-geologic and mathematical aspect of complex problem of interpretation of gravity anomalies. The rational methods of localization of anomalies are examined in detail. All methods of interpreting gravity anomalies are described which have found successful application in practice. Also given are ideas of some new methods of the interpretation of gravity anomalies, the prospects for further development and industrial testing. Numerous practical examples to interpretation are given. Partial Contents: Bases of gravitational field theory; Physico-geologic bases of gravitational prospecting; Principles of geologic interpretation of gravity anomalies; Conversions and calculations of anomalies; Interpretation of gravity anomalies for bodies of correct geometric form and for bodies of arbitrary form; Geologic interpretation of the results of regional gravitational photographing; Searches and prospecting of oil- and gas-bearing structures and of deposits of ore and nonmetalliferous useful minerals.
Drawdown behavior of gravity drainage wells
Aasen, J.A.; Ramey, H.J. Jr.
1993-10-01
An analytical solution for drawdown in gravity drainage wells is developed. The free-surface flow is viewed as incompressible, and anisotropy effects are included. The well is a line source well, and the reservoir is infinitely large. The model is valid for small drawdowns. The uniform wellbore potential inner boundary condition is modelled using the proper Green`s function. The discontinuity at the wellbore is solved by introducing a finite skin radius, and the formulation produces a seepage face. The calculated wellbore flux distribution and wellbore pressures are in fair agreement with results obtained using a numerical gravity drainage simulator. Three distinct flow periods are observed. The wellbore storage period is caused by the moving liquid level, and the duration is short. During the long intermediate flow period, the wellbore pressure is nearly constant. In this period the free surface moves downwards, and the liquid is produced mainly by vertical drainage. At long times the semilog straight line appears. The confined liquid solutions by Theis (1935) and van Everdingen and Hurst (1949) may be used during the pseudoradial flow period if the flowrate is low. New type curves are presented that yield both vertical and horizontal permeabilities.
Category:Gravity Techniques | Open Energy Information
OpenEI (Open Energy Information) [EERE & EIA]
the following 3 subcategories, out of 3 total. A Airborne Gravity Survey 1 pages G Ground Gravity Survey 1 pages M Microgravity-Hybrid Microgravity 1 pages...
Cosmological stability bound in massive gravity and bigravity
Fasiello, Matteo; Tolley, Andrew J. E-mail: andrew.j.tolley@case.edu
2013-12-01
We give a simple derivation of a cosmological bound on the graviton mass for spatially flat FRW solutions in massive gravity with an FRW reference metric and for bigravity theories. This bound comes from the requirement that the kinetic term of the helicity zero mode of the graviton is positive definite. The bound is dependent only on the parameters in the massive gravity potential and the Hubble expansion rate for the two metrics. We derive the decoupling limit of bigravity and FRW massive gravity, and use this to give an independent derivation of the cosmological bound. We recover our previous results that the tension between satisfying the Friedmann equation and the cosmological bound is sufficient to rule out all observationally relevant FRW solutions for massive gravity with an FRW reference metric. In contrast, in bigravity this tension is resolved due to different nature of the Vainshtein mechanism. We find that in bigravity theories there exists an FRW solution with late-time self-acceleration for which the kinetic terms for the helicity-2, helicity-1 and helicity-0 are generically nonzero and positive making this a compelling candidate for a model of cosmic acceleration. We confirm that the generalized bound is saturated for the candidate partially massless (bi)gravity theories but the existence of helicity-1/helicity-0 interactions implies the absence of the conjectured partially massless symmetry for both massive gravity and bigravity.
Bulalo field, Philippines: Reservoir modeling for prediction of limits to sustainable generation
Strobel, Calvin J.
1993-01-28
The Bulalo geothermal field, located in Laguna province, Philippines, supplies 12% of the electricity on the island of Luzon. The first 110 MWe power plant was on line May 1979; current 330 MWe (gross) installed capacity was reached in 1984. Since then, the field has operated at an average plant factor of 76%. The National Power Corporation plans to add 40 MWe base load and 40 MWe standby in 1995. A numerical simulation model for the Bulalo field has been created that matches historic pressure changes, enthalpy and steam flash trends and cumulative steam production. Gravity modeling provided independent verification of mass balances and time rate of change of liquid desaturation in the rock matrix. Gravity modeling, in conjunction with reservoir simulation provides a means of predicting matrix dry out and the time to limiting conditions for sustainable levelized steam deliverability and power generation.
A new quasidilaton theory of massive gravity
Mukohyama, Shinji
2014-12-01
We present a new quasidilaton theory of Poincare invariant massive gravity, based on the recently proposed framework of matter coupling that makes it possible for the kinetic energy of the quasidilaton scalar to couple to both physical and fiducial metrics simultaneously. We find a scaling-type exact solution that expresses a self-accelerating de Sitter universe, and then analyze linear perturbations around it. It is shown that in a range of parameters all physical degrees of freedom have non-vanishing quadratic kinetic terms and are stable in the subhorizon limit, while the effective Newton's constant for the background is kept positive.
A high frequency resonance gravity gradiometer
Bagaev, S. N.; Kvashnin, N. L.; Skvortsov, M. N.; Bezrukov, L. B.; Krysanov, V. A.; Oreshkin, S. I.; Motylev, A. M.; Popov, S. M.; Samoilenko, A. A.; Yudin, I. S.; Rudenko, V. N.
2014-06-15
A new setup OGRAN—the large scale opto-acoustical gravitational detector is described. As distinguished from known gravitational bar detectors it uses the optical interferometrical readout for registering weak variations of gravity gradient at the kilohetz frequency region. At room temperature, its sensitivity is limited only by the bar Brownian noise at the bandwidth close to 100 Hz. It is destined for a search for rare events—gravitational pulses coincident with signals of neutrino scintillator (BUST) in the deep underground of Baksan Neutrino Observatory of INR RAS.
DETECTING GRAVITY MODES IN THE SOLAR {sup 8} B NEUTRINO FLUX
Lopes, Ilídio; Turck-Chičze, Sylvaine E-mail: ilopes@uevora.pt
2014-09-10
The detection of gravity modes produced in the solar radiative zone has been a challenge in modern astrophysics for more than 30 yr and their amplitude in the core is not yet determined. In this Letter, we develop a new strategy to look for standing gravity modes through solar neutrino fluxes. We note that due to a resonance effect, the gravity modes of low degree and low order have the largest impact on the {sup 8} B neutrino flux. The strongest effect is expected to occur for the dipole mode with radial order 2, corresponding to periods of about 1.5 hr. These standing gravity waves produce temperature fluctuations that are amplified by a factor of 170 in the boron neutrino flux for the corresponding period, in consonance with the gravity modes. From current neutrino observations, we determine that the maximum temperature variation due to the gravity modes in the Sun's core is smaller than 5.8 × 10{sup –4}. This study clearly shows that due to their high sensitivity to the temperature, the {sup 8} B neutrino flux time series is an excellent tool to determine the properties of gravity modes in the solar core. Moreover, if gravity mode footprints are discovered in the {sup 8} B neutrino flux, this opens a new line of research to probe the physics of the solar core as non-standing gravity waves of higher periods cannot be directly detected by helioseismology but could leave their signature on boron neutrino or on other neutrino fluxes.
Quantum Field Theory & Gravity
U.S. Department of Energy (DOE) - all webpages (Extended Search)
Quantum Field Theory & Gravity Quantum Field Theory & Gravity Understanding discoveries at the Energy, Intensity, and Cosmic Frontiers Get Expertise Rajan Gupta (505) 667-7664 Email Bruce Carlsten (505) 667-5657 Email Quantum Field Theory and Gravity at Los Alamos The HEP effort at Los Alamos in this area is actively pursing a number of questions in this area. What is the final state of complete gravitational collapse? What happens at the event horizon? What is dark energy? How did the
Waste Isolation Pilot Plant (WIPP) site gravity survey and interpretation
Barrows, L.J.; Fett, J.D.
1983-04-01
A portion of the WIPP site has been extensively surveyed with high-precision gravity. The main survey (in T22S, R31E) covered a rectangular area 2 by 4-1/3 mi encompassing all of WIPP site Zone II and part of the disturbed zone to the north of the site. Stations were at 293-ft intervals along 13 north-south lines 880 ft apart. The data are considered accurate to within a few hundredths of a milligal. Long-wavelength gravity anomalies correlate well with seismic time structures on horizons below the Castile Formation. Both the gravity anomalies and the seismic time structures are interpreted as resulting from related density and velocity variations within the Ochoan Series. Shorter wavelength negative gravity anomalies are interpreted as resulting from bulk density alteration in the vicinity of karst conduits. The WIPP gravity survey was unable to resolve low-amplitude, long-wavelength anomalies that should result from the geologic structures within the disturbed zone. It did indicate the degree and character of karst development within the surveyed area.
Positive signs in massive gravity
Cheung, Clifford; Remmen, Grant N.
2016-04-01
Here, we derive new constraints on massive gravity from unitarity and analyticity of scattering amplitudes. Our results apply to a general effective theory defined by Einstein gravity plus the leading soft diffeomorphism-breaking corrections. We calculate scattering amplitudes for all combinations of tensor, vector, and scalar polarizations. Furthermore, the high-energy behavior of these amplitudes prescribes a specific choice of couplings that ameliorates the ultraviolet cutoff, in agreement with existing literature. We then derive consistency conditions from analytic dispersion relations, which dictate positivity of certain combinations of parameters appearing in the forward scattering amplitudes. These constraints exclude all but a small islandmoreÂ Â» in the parameter space of ghost-free massive gravity. And while the theory of the "Galileon" scalar mode alone is known to be inconsistent with positivity constraints, this is remedied in the full massive gravity theory.Â«Â less
Cosmological perturbations in unimodular gravity
Gao, Caixia; Brandenberger, Robert H.; Cai, Yifu; Chen, Pisin E-mail: rhb@hep.physics.mcgill.ca E-mail: chen@slac.stanford.edu
2014-09-01
We study cosmological perturbation theory within the framework of unimodular gravity. We show that the Lagrangian constraint on the determinant of the metric required by unimodular gravity leads to an extra constraint on the gauge freedom of the metric perturbations. Although the main equation of motion for the gravitational potential remains the same, the shift variable, which is gauge artifact in General Relativity, cannot be set to zero in unimodular gravity. This non-vanishing shift variable affects the propagation of photons throughout the cosmological evolution and therefore modifies the Sachs-Wolfe relation between the relativistic gravitational potential and the microwave temperature anisotropies. However, for adiabatic fluctuations the difference between the result in General Relativity and unimodular gravity is suppressed on large angular scales. Thus, no strong constraints on the theory can be derived.
Extended Horava gravity and Einstein-aether theory
Jacobson, Ted
2010-05-15
Einstein-aether theory is general relativity coupled to a dynamical, unit timelike vector. If this vector is restricted in the action to be hypersurface orthogonal, the theory is identical to the IR limit of the extension of Horava gravity proposed by Blas, Pujolas and Sibiryakov. Hypersurface orthogonal solutions of Einstein-aether theory are solutions to the IR limit of this theory, hence numerous results already obtained for Einstein-aether theory carry over.
WILSON-BAPPU EFFECT: EXTENDED TO SURFACE GRAVITY
Park, Sunkyung; Kang, Wonseok; Lee, Jeong-Eun; Lee, Sang-Gak E-mail: wskang@khu.ac.kr E-mail: sanggak@snu.ac.kr
2013-10-01
In 1957, Wilson and Bappu found a tight correlation between the stellar absolute visual magnitude (M{sub V} ) and the width of the Ca II K emission line for late-type stars. Here, we revisit the Wilson-Bappu relationship (WBR) to claim that the WBR can be an excellent indicator of stellar surface gravity of late-type stars as well as a distance indicator. We have measured the width (W) of the Ca II K emission line in high-resolution spectra of 125 late-type stars obtained with the Bohyunsan Optical Echelle Spectrograph and adopted from the Ultraviolet and Visual Echelle Spectrograph archive. Based on our measurement of the emission line width (W), we have obtained a WBR of M{sub V} = 33.76 - 18.08 log W. In order to extend the WBR to being a surface gravity indicator, stellar atmospheric parameters such as effective temperature (T{sub eff}), surface gravity (log g), metallicity ([Fe/H]), and micro-turbulence ({xi}{sub tur}) have been derived from self-consistent detailed analysis using the Kurucz stellar atmospheric model and the abundance analysis code, MOOG. Using these stellar parameters and log W, we found that log g = -5.85 log W+9.97 log T{sub eff} - 23.48 for late-type stars.
Further stable neutron star models from f(R) gravity
Astashenok, Artyom V.; Capozziello, Salvatore; Odintsov, Sergei D. E-mail: capozziello@na.infn.it
2013-12-01
Neutron star models in perturbative f(R) gravity are considered with realistic equations of state. In particular, we consider the FPS, SLy and other equations of state and a case of piecewise equation of state for stars with quark cores. The mass-radius relations for f(R) = R+R(e{sup ?R/R{sub 0}}?1) model and for R{sup 2} models with logarithmic and cubic corrections are obtained. In the case of R{sup 2} gravity with cubic corrections, we obtain that at high central densities (? > 10?{sub ns}, where ?{sub ns} = 2.7 × 10{sup 14} g/cm{sup 3} is the nuclear saturation density), stable star configurations exist. The minimal radius of such stars is close to 9 km with maximal mass ? 1.9M{sub ?} (SLy equation). A similar situation takes place for AP4 and BSK20 EoS. Such an effect can give rise to more compact stars than in General Relativity. If observationally identified, such objects could constitute a formidable signature for modified gravity at astrophysical level. Another interesting result can be achieved in modified gravity with only a cubic correction. For some EoS, the upper limit of neutron star mass increases and therefore these EoS can describe realistic star configurations (although, in General Relativity, these EoS are excluded by observational constraints)
How does gravity save or kill Q-balls?
Tamaki, Takashi; Sakai, Nobuyuki
2011-02-15
We explore stability of gravitating Q-balls with potential V{sub 4}({phi})=(m{sup 2}/2){phi}{sup 2}-{lambda}{phi}{sup 4}+({phi}{sup 6}/M{sup 2}) via catastrophe theory, as an extension of our previous work on Q-balls with potential V{sub 3}({phi})=(m{sup 2}/2){phi}{sup 2}-{mu}{phi}{sup 3}+{lambda}{phi}{sup 4}. In flat spacetime Q-balls with V{sub 4} in the thick-wall limit are unstable and there is a minimum charge Q{sub min}, where Q-balls with Qgravity into account, on the other hand, there exist stable Q-balls with arbitrarily small charge, no matter how weak gravity is. That is, gravity saves Q-balls with small charge. We also show how stability of Q-balls changes as gravity becomes strong.
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Grand Coulee Transmission Line Replacement Project Hooper Springs McNary-John Day Montana-to-Washington Transmission System Upgrade Project - M2W Olympia-Grand Coulee No. 1...
Unexpected Cancellations in Gravity Theories
Bern, Z.; Carrasco, J.J.; Forde, D.; Ita, H.; Johansson, H.; /UCLA
2007-07-13
Recent computations of scattering amplitudes show that N = 8 supergravity is surprisingly well behaved in the ultraviolet and may even be ultraviolet finite in perturbation theory. The novel cancellations necessary for ultraviolet finiteness first appear at one loop in the guise of the ''no-triangle hypothesis''. We study one-loop amplitudes in pure Einstein gravity and point out the existence of cancellations similar to those found previously in N = 8 supergravity. These cancellations go beyond those found in the one-loop effective action. Using unitarity, this suggests that generic theories of quantum gravity based on the Einstein-Hilbert action may be better behaved in the ultraviolet at higher loops than suggested by naive power counting, though without additional (supersymmetric) cancellations they diverge. We comment on future studies that should be performed to support this proposal.
Measurement analysis and quantum gravity
Albers, Mark; Kiefer, Claus; Reginatto, Marcel
2008-09-15
We consider the question of whether consistency arguments based on measurement theory show that the gravitational field must be quantized. Motivated by the argument of Eppley and Hannah, we apply a DeWitt-type measurement analysis to a coupled system that consists of a gravitational wave interacting with a mass cube. We also review the arguments of Eppley and Hannah and of DeWitt, and investigate a second model in which a gravitational wave interacts with a quantized scalar field. We argue that one cannot conclude from the existing gedanken experiments that gravity has to be quantized. Despite the many physical arguments which speak in favor of a quantum theory of gravity, it appears that the justification for such a theory must be based on empirical tests and does not follow from logical arguments alone.
Emergent Horava gravity in graphene
Volovik, G.E.; L. D. Landau Institute for Theoretical Physics, Kosygina 2, 119334 Moscow ; Zubkov, M.A.
2014-01-15
First of all, we reconsider the tight-binding model of monolayer graphene, in which the variations of the hopping parameters are allowed. We demonstrate that the emergent 2D Weitzenbock geometry as well as the emergent U(1) gauge field appear. The emergent gauge field is equal to the linear combination of the components of the zweibein. Therefore, we actually deal with the gauge fixed version of the emergent 2+1 D teleparallel gravity. In particular, we work out the case, when the variations of the hopping parameters are due to the elastic deformations, and relate the elastic deformations with the emergent zweibein. Next, we investigate the tight-binding model with the varying intralayer hopping parameters for the multilayer graphene with the ABC stacking. In this case the emergent 2D Weitzenbock geometry and the emergent U(1) gauge field appear as well, and the emergent low energy effective field theory has the anisotropic scaling. -- Highlights: •The tight-binding model for graphene with varying hopping parameters is considered. •The emergent gravity and emergent gauge fields are derived. •For the case of the multilayer graphene we obtain the analogue of Horava gravity with anisotropic scaling.
Gravity monitoring of CO2 movement during sequestration: Model studies
Gasperikova, E.; Hoversten, G.M.
2008-07-15
We examine the relative merits of gravity measurements as a monitoring tool for geological CO{sub 2} sequestration in three different modeling scenarios. The first is a combined CO{sub 2} enhanced oil recovery (EOR) and sequestration in a producing oil field, the second is sequestration in a brine formation, and the third is for a coalbed methane formation. EOR/sequestration petroleum reservoirs have relatively thin injection intervals with multiple fluid components (oil, hydrocarbon gas, brine, and CO{sub 2}), whereas brine formations usually have much thicker injection intervals and only two components (brine and CO{sub 2}). Coal formations undergoing methane extraction tend to be thin (3-10 m), but shallow compared to either EOR or brine formations. The injection of CO{sub 2} into the oil reservoir produced a bulk density decrease in the reservoir. The spatial pattern of the change in the vertical component of gravity (G{sub z}) is directly correlated with the net change in reservoir density. Furthermore, time-lapse changes in the borehole G{sub z} clearly identified the vertical section of the reservoir where fluid saturations are changing. The CO{sub 2}-brine front, on the order of 1 km within a 20 m thick brine formation at 1900 m depth, with 30% CO{sub 2} and 70% brine saturations, respectively, produced a -10 Gal surface gravity anomaly. Such anomaly would be detectable in the field. The amount of CO{sub 2} in a coalbed methane test scenario did not produce a large enough surface gravity response; however, we would expect that for an industrial size injection, the surface gravity response would be measurable. Gravity inversions in all three scenarios illustrated that the general position of density changes caused by CO{sub 2} can be recovered, but not the absolute value of the change. Analysis of the spatial resolution and detectability limits shows that gravity measurements could, under certain circumstances, be used as a lower-cost alternative to seismic
Ground Gravity Survey | Open Energy Information
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Et Al., 2000) Dixie Valley Geothermal Area 1999 2000 Precise Gravimetry and Geothermal Reservoir Management Ground Gravity Survey At Dixie Valley Geothermal Area (Blackwell, Et...
Growth histories in bimetric massive gravity
Berg, Marcus; Buchberger, Igor; Enander, Jonas; Mörtsell, Edvard; Sjörs, Stefan E-mail: igor.buchberger@kau.se E-mail: edvard@fysik.su.se
2012-12-01
We perform cosmological perturbation theory in Hassan-Rosen bimetric gravity for general homogeneous and isotropic backgrounds. In the de Sitter approximation, we obtain decoupled sets of massless and massive scalar gravitational fluctuations. Matter perturbations then evolve like in Einstein gravity. We perturb the future de Sitter regime by the ratio of matter to dark energy, producing quasi-de Sitter space. In this more general setting the massive and massless fluctuations mix. We argue that in the quasi-de Sitter regime, the growth of structure in bimetric gravity differs from that of Einstein gravity.
Airborne Gravity Survey | Open Energy Information
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Gravity Techniques Information Provided by Technique Lithology: Distribution of density in the subsurface enables inference of rock type. StratigraphicStructural:...
Simultaneous measurement of gravity acceleration and gravity gradient with an atom interferometer
Sorrentino, F.; Lien, Y.-H.; Rosi, G.; Tino, G. M.; Bertoldi, A.; Bodart, Q.; Cacciapuoti, L.; Angelis, M. de; Prevedelli, M.
2012-09-10
We demonstrate a method to measure the gravitational acceleration with a dual cloud atom interferometer; the use of simultaneous atom interferometers reduces the effect of seismic noise on the gravity measurement. At the same time, the apparatus is capable of accurate measurements of the vertical gravity gradient. The ability to determine the gravity acceleration and gravity gradient simultaneously and with the same instrument opens interesting perspectives in geophysical applications.
Negative mass solitons in gravity
Cebeci, Hakan; Sarioglu, Oezguer; Tekin, Bayram
2006-03-15
We first reconstruct the conserved (Abbott-Deser) charges in the spin-connection formalism of gravity for asymptotically (Anti)-de Sitter spaces, and then compute the masses of the AdS soliton and the recently found Eguchi-Hanson solitons in generic odd dimensions, unlike the previous result obtained for only five dimensions. These solutions have negative masses compared to the global AdS or AdS/Z{sub p} spacetimes. As a separate note, we also compute the masses of the recent even dimensional Taub-NUT-Reissner-Nordstroem metrics.
Office of Energy Efficiency and Renewable Energy (EERE)
Dose Limits ERAD (Question Posted to ERAD in May 2012) Who do you define as a member of the public for the onsite MEI? This question implies that there may be more than one maximally exposed individual (MEI), one on-site and one off-site, when demonstrating compliance with the Public Dose Limit of DOE Order 458.1. Although all potential MEIs should be considered and documented, as well as the calculated doses and pathways considered, the intent of DOE Order 458.1 is in fact to ultimately identify only one MEI, a theoretical individual who could be either on-site or off-site.
Naked singularities and quantum gravity
Harada, Tomohiro; Iguchi, Hideo; Nakao, Ken-ichi; Singh, T. P.; Tanaka, Takahiro; Vaz, Cenalo
2001-08-15
There are known models of spherical gravitational collapse in which the collapse ends in a naked shell-focusing singularity for some initial data. If a massless scalar field is quantized on the classical background provided by such a star, it is found that the outgoing quantum flux of the scalar field diverges in the approach to the Cauchy horizon. We argue that the semiclassical approximation (i.e., quantum field theory on a classical curved background) used in these analyses ceases to be valid about one Planck time before the epoch of naked singularity formation, because by then the curvature in the central region of the star reaches the Planck scale. It is shown that during the epoch in which the semiclassical approximation is valid, the total emitted energy is about one Planck unit, and is not divergent. We also argue that back reaction in this model does not become important so long as gravity can be treated classically. It follows that the further evolution of the star will be determined by quantum gravitational effects, and without invoking quantum gravity it is not possible to say whether the star radiates away on a short time scale or settles down into a black hole state.
A cosmological study in massive gravity theory
Pan, Supriya Chakraborty, Subenoy
2015-09-15
A detailed study of the various cosmological aspects in massive gravity theory has been presented in the present work. For the homogeneous and isotropic FLRW model, the deceleration parameter has been evaluated, and, it has been examined whether there is any transition from deceleration to acceleration in recent past, or not. With the proper choice of the free parameters, it has been shown that the massive gravity theory is equivalent to Einstein gravity with a modified Newtonian gravitational constant together with a negative cosmological constant. Also, in this context, it has been examined whether the emergent scenario is possible, or not, in massive gravity theory. Finally, we have done a cosmographic analysis in massive gravity theory.
Transmission line capital costs
Hughes, K.R.; Brown, D.R.
1995-05-01
The displacement or deferral of conventional AC transmission line installation is a key benefit associated with several technologies being developed with the support of the U.S. Department of Energy`s Office of Energy Management (OEM). Previous benefits assessments conducted within OEM have been based on significantly different assumptions for the average cost per mile of AC transmission line. In response to this uncertainty, an investigation of transmission line capital cost data was initiated. The objective of this study was to develop a database for preparing preliminary estimates of transmission line costs. An extensive search of potential data sources identified databases maintained by the Bonneville Power Administration (BPA) and the Western Area Power Administration (WAPA) as superior sources of transmission line cost data. The BPA and WAPA data were adjusted to a common basis and combined together. The composite database covers voltage levels from 13.8 to 765 W, with cost estimates for a given voltage level varying depending on conductor size, tower material type, tower frame type, and number of circuits. Reported transmission line costs vary significantly, even for a given voltage level. This can usually be explained by variation in the design factors noted above and variation in environmental and land (right-of-way) costs, which are extremely site-specific. Cost estimates prepared from the composite database were compared to cost data collected by the Federal Energy Regulatory Commission (FERC) for investor-owned utilities from across the United States. The comparison was hampered because the only design specifications included with the FERC data were voltage level and line length. Working within this limitation, the FERC data were not found to differ significantly from the composite database. Therefore, the composite database was judged to be a reasonable proxy for estimating national average costs.
Negative Effective Gravity in Water Waves by Periodic Resonator...
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Negative Effective Gravity in Water Waves by Periodic Resonator Arrays Prev Next Title: Negative Effective Gravity in Water Waves by Periodic Resonator Arrays Authors: Hu,...
Ground Gravity Survey At Clear Lake Area (Skokan, 1993) | Open...
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Ground Gravity Survey At Clear Lake Area (Skokan, 1993) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At Clear Lake Area...
A new quasidilaton theory of massive gravity (Journal Article...
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A new quasidilaton theory of massive gravity Citation Details In-Document Search Title: A new quasidilaton theory of massive gravity We present a new quasidilaton theory of...
Ground Gravity Survey At Coso Geothermal Area (1980) | Open Energy...
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Ground Gravity Survey At Coso Geothermal Area (1980) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At Coso Geothermal...
Ground Gravity Survey At Crump's Hot Springs Area (DOE GTP) ...
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Category:Airborne Gravity Survey | Open Energy Information
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Category Edit History Category:Airborne Gravity Survey Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Geothermalpower.jpg Looking for the Airborne Gravity Survey...
Ground Gravity Survey At North Brawley Geothermal Area (Biehler...
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Ground Gravity Survey At North Brawley Geothermal Area (Biehler, 1964) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At...
Ground Gravity Survey At Cove Fort Area - Vapor (Warpinski, Et...
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Ground Gravity Survey At Cove Fort Area - Vapor (Warpinski, Et Al., 2002) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey...
Ground Gravity Survey At Kilauea East Rift Geothermal Area (FURUMOTO...
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Ground Gravity Survey At Kilauea East Rift Geothermal Area (FURUMOTO, 1976) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey...
Ground Gravity Survey At Snake River Plain Region (DOE GTP) ...
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Ground Gravity Survey At Snake River Plain Region (DOE GTP) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At Snake River...
Ground Gravity Survey At Kilauea East Rift Geothermal Area (Thomas...
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Ground Gravity Survey At Kilauea East Rift Geothermal Area (Thomas, 1986) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey...
Ground Gravity Survey At Kilauea East Rift Geothermal Area (Broyles...
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Ground Gravity Survey At Kilauea East Rift Geothermal Area (Broyles, Et Al., 1979) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity...
Integration of Full Tensor Gravity and ZTEM Passive Low Frequency...
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Data Acquisition Integration of Full Tensor Gravity and ZTEM Passive Low Frequency EM Instruments for Simultaneous Data Acquisition Integration of Full Tensor Gravity and ...
Landed Costs of Imported Crude by API Gravity
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API Gravity (Dollars per Barrel) Period: Monthly Annual Download Series History Download Series History Definitions, Sources & Notes Definitions, Sources & Notes API Gravity Sep-15 ...
Cosmological singularities in Born-Infeld determinantal gravity...
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Problems with propagation and time evolution in f ( T ) gravity...
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Disformal theories of gravity: from the solar system to cosmology
Sakstein, Jeremy
2014-12-01
This paper is concerned with theories of gravity that contain a scalar coupled both conformally and disformally to matter through the metric. By systematically deriving the non-relativistic limit, it is shown that no new non-linear screening mechanisms are present beyond the Vainshtein mechanism and chameleon-like screening. If one includes the cosmological expansion of the universe, disformal effects that are usually taken to be absent can be present in the solar system. When the conformal factor is absent, fifth-forces can be screened on all scales when the cosmological field is slowly-rolling. We investigate the cosmology of these models and use local tests of gravity to place new constraints on the disformal coupling and find M ?> O(eV), which is not competitive with laboratory tests. Finally, we discuss the future prospects for testing these theories and the implications for other theories of modified gravity. In particular, the Vainshtein radius of solar system objects can be altered from the static prediction when cosmological time-derivatives are non-negligible.
Dust gravitational drift wave in complex plasma under gravity
Salahshoor, M. Niknam, A. R.
2014-12-15
The dispersion relation of electrostatic waves in a complex plasma under gravity is presented. It is assumed that the waves propagate parallel to the external fields. The effects of weak electric field, neutral drag force, and ion drag force are also taken into account. The dispersion relation is numerically examined in an appropriate parameter space in which the gravity plays the dominant role in the dynamics of microparticles. The numerical results show that, in the low pressure complex plasma under gravity, a low frequency drift wave can be developed in the long wavelength limit. The stability state of this wave is switched at a certain critical wavenumber in such a way that the damped mode is transformed into a growing one. Furthermore, the influence of the external fields on the dispersion properties is analyzed. It is shown that the wave instability is essentially due to the electrostatic streaming of plasma particles. It is also found that by increasing the electric field strength, the stability switching occurs at smaller wavenumbers.
Astrophysical tests of modified gravity: the morphology and kinematics of dwarf galaxies
Vikram, Vinu; Cabré, Anna; Jain, Bhuvnesh; VanderPlas, J.T. E-mail: annanusca@gmail.com E-mail: jakevdp@cs.washington.edu
2013-08-01
This paper is the third in a series on tests of gravity using observations of stars and nearby dwarf galaxies. We carry out four distinct tests using published data on the kinematics and morphology of dwarf galaxies, motivated by the theoretical work of Hui et al. (2009) and Jain and Vanderplas (2011). In a wide class of gravity theories a scalar field couples to matter and provides an attractive fifth force. Due to their different self-gravity, stars and gas may respond differently to the scalar force leading to several observable deviations from standard gravity. HI gas, red giant stars and main sequence stars can be displaced relative to each other, and the stellar disk can display warps or asymmetric rotation curves aligned with external potential gradients. To distinguish the effects of modified gravity from standard astrophysical phenomena, we use a control sample of galaxies that are expected to be screened from the fifth force. In all cases we find no significant deviation from the null hypothesis of general relativity. The limits obtained from dwarf galaxies are not yet competitive with the limits from cepheids obtained in our first paper, but can be improved to probe regions of parameter space that are inaccessible using other tests. We discuss how our methodology can be applied to new radio and optical observations of nearby galaxies.
Gauge natural formulation of conformal gravity
Campigotto, M.; Fatibene, L.
2015-03-15
We consider conformal gravity as a gauge natural theory. We study its conservation laws and superpotentials. We also consider the Mannheim and Kazanas spherically symmetric vacuum solution and discuss conserved quantities associated to conformal and diffeomorphism symmetries.
Bouguer gravity map | Open Energy Information
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LibraryAdd to library Map: Bouguer gravity mapInfo GraphicMapChart Cartographers J. Behrendt and L. Bajwa Organization U.S. Geological Survey Published U.S. Geological...
Quantum gravity and renormalization: The tensor track
Rivasseau, Vincent
2012-06-27
We propose a new program to quantize and renormalize gravity based on recent progress on the analysis of large random tensors. We compare it briefly with other existing approaches.
Gravity waves from cosmic bubble collisions
Salem, Michael P.; Saraswat, Prashant; Shaghoulian, Edgar E-mail: ps88@stanford.edu
2013-02-01
Our local Hubble volume might be contained within a bubble that nucleated in a false vacuum with only two large spatial dimensions. We study bubble collisions in this scenario and find that they generate gravity waves, which are made possible in this context by the reduced symmetry of the global geometry. These gravity waves would produce B-mode polarization in the cosmic microwave background, which could in principle dominate over the inflationary background.
Measuring antimatter gravity with muonium
Kaplan, Daniel M.; Kirch, Klaus; Mancini, Derrick; Phillips, James D.; Phillips, Thomas J.; Roberts, Thomas J.; Terry, Jeff; Bravina, L.; Foka, Y.; Kabana, S.
2015-05-29
The gravitational acceleration of antimatter, ÂŻg, has never been directly measured and could bear importantly on our understanding of gravity, the possible existence of a fifth force, and the nature and early history of the universe. Only two avenues for such a measurement appear to be feasible: antihydrogen and muonium. The muonium measurement requires a novel, monoenergetic, low-velocity, horizontal muonium beam directed at an atom interferometer. The precision three-grating interferometer can be produced in silicon nitride or ultrananocrystalline diamond using state-of-the-art nanofabrication. The required precision alignment and calibration at the picometer level also appear to be feasible. With 100 nmmoreÂ Â» grating pitch, a 10% measurement of ÂŻg can be made using some months of surface-muon beam time, and a 1% or better measurement with a correspondingly larger exposure. This could constitute the first gravitational measurement of leptonic matter, of 2nd-generation matter and, possibly, the first measurement of the gravitational acceleration of antimatter.Â«Â less
Nonderivative modified gravity: a classification
Comelli, D.; Nesti, F.; Pilo, L. E-mail: fabrizio.nesti@irb.hr
2014-11-01
We analyze the theories of gravity modified by a generic nonderivative potential built from the metric, under the minimal requirement of unbroken spatial rotations. Using the canonical analysis, we classify the potentials V according to the number of degrees of freedom (DoF) that propagate at the nonperturbative level. We then compare the nonperturbative results with the perturbative DoF propagating around Minkowski and FRW backgrounds. A generic V implies 6 propagating DoF at the non-perturbative level, with a ghost on Minkowski background. There exist potentials which propagate 5 DoF, as already studied in previous works. Here, no V with unbroken rotational invariance admitting 4 DoF is found. Theories with 3 DoF turn out to be strongly coupled on Minkowski background. Finally, potentials with only the 2 DoF of a massive graviton exist. Their effect on cosmology is simply equivalent to a cosmological constant. Potentials with 2 or 5 DoF and explicit time dependence appear to be a further viable possibility.
Measuring antimatter gravity with muonium
Kaplan, Daniel M.; Kirch, Klaus; Mancini, Derrick; Phillips, James D.; Phillips, Thomas J.; Roberts, Thomas J.; Terry, Jeff; Bravina, L.; Foka, Y.; Kabana, S.
2015-05-29
The gravitational acceleration of antimatter, ÂŻg, has never been directly measured and could bear importantly on our understanding of gravity, the possible existence of a fifth force, and the nature and early history of the universe. Only two avenues for such a measurement appear to be feasible: antihydrogen and muonium. The muonium measurement requires a novel, monoenergetic, low-velocity, horizontal muonium beam directed at an atom interferometer. The precision three-grating interferometer can be produced in silicon nitride or ultrananocrystalline diamond using state-of-the-art nanofabrication. The required precision alignment and calibration at the picometer level also appear to be feasible. With 100 nm grating pitch, a 10% measurement of ÂŻg can be made using some months of surface-muon beam time, and a 1% or better measurement with a correspondingly larger exposure. This could constitute the first gravitational measurement of leptonic matter, of 2nd-generation matter and, possibly, the first measurement of the gravitational acceleration of antimatter.
Inflation in Kaluza-Klein cosmology. 1; Transformation to fourth-order gravity
Schmidt, H.J. )
1990-12-20
This paper reports on the higher- dimensional Einstein equation with {Gamma}-term shown to be comformally equivalent to the four-dimensional field equation of scale-invariant fourth-order gravity. This holds for a general warped product between space-time and internal space of arbitrary dimension m which turns out to be an Einstein space. (The limit m {yields} {infinity} makes sense ) Thus, the results concerning the attractor property of the power- law inflationary solution derived for fourth-order gravity hold for the Kaluza-Klein model, too.
Universality of the acceleration due to gravity on the surface of a rapidly rotating neutron star
AlGendy, Mohammad; Morsink, Sharon M.
2014-08-20
On the surface of a rapidly rotating neutron star, the effective centrifugal force decreases the effective acceleration due to gravity (as measured in the rotating frame) at the equator while increasing the acceleration at the poles due to the centrifugal flattening of the star into an oblate spheroid. We compute the effective gravitational acceleration for relativistic rapidly rotating neutron stars and show that for a star with mass M, equatorial radius R{sub e} , and angular velocity ?, the deviations of the effective acceleration due to gravity from the nonrotating case take on a universal form that depends only on the compactness ratio M/R{sub e} , the dimensionless square of the angular velocity ?{sup 2}R{sub e}{sup 3}/GM, and the latitude on the star's surface. This dependence is universal, in that it has very little dependence on the neutron star's equation of state. The effective gravity is expanded in the slow-rotation limit to show the dependence on the effective centrifugal force, oblate shape of the star, and the quadrupole moment of the gravitational field. In addition, an empirical fit and simple formula for the effective gravity is found. We find that the increase in the acceleration due to gravity at the poles is of the same order of magnitude as the decrease in the effective acceleration due to gravity at the equator for all realistic value of mass, radius, and spin. For neutron stars that spin with frequencies near 600 Hz, the difference between the effective gravity at the poles and the equator is about 20%.
Massive gravity wrapped in the cosmic web
Shim, Junsup; Lee, Jounghun; Li, Baojiu E-mail: jounghun@astro.snu.ac.kr
2014-03-20
We study how the filamentary pattern of the cosmic web changes if the true gravity deviates from general relativity (GR) on a large scale. The f(R) gravity, whose strength is controlled to satisfy the current observational constraints on the cluster scale, is adopted as our fiducial model and a large, high-resolution N-body simulation is utilized for this study. By applying the minimal spanning tree algorithm to the halo catalogs from the simulation at various epochs, we identify the main stems of the rich superclusters located in the most prominent filamentary section of the cosmic web and determine their spatial extents per member cluster to be the degree of their straightness. It is found that the f(R) gravity has the effect of significantly bending the superclusters and that the effect becomes stronger as the universe evolves. Even in the case where the deviation from GR is too small to be detectable by any other observables, the degree of the supercluster straightness exhibits a conspicuous difference between the f(R) and the GR models. Our results also imply that the supercluster straightness could be a useful discriminator of f(R) gravity from the coupled dark energy since it is shown to evolve differently between the two models. As a final conclusion, the degree of the straightness of the rich superclusters should provide a powerful cosmological test of large scale gravity.
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Charged black holes in generalized teleparallel gravity
Rodrigues, M.E.; Houndjo, M.J.S.; Tossa, J.; Momeni, D.; Myrzakulov, R. E-mail: sthoundjo@yahoo.fr E-mail: d.momeni@yahoo.com
2013-11-01
In this paper we investigate charged static black holes in 4D for generalized teleparallel models of gravity, based on torsion as the geometric object for describing gravity according to the equivalence principle. As a motivated idea, we introduce a set of non-diagonal tetrads and derive the full system of non linear differential equations. We prove that the common Schwarzschild gauge is applicable only when we study linear f(T) case. We reobtain the Reissner-Nordstrom-de Sitter (or RN-AdS) solution for the linear case of f(T) and perform a parametric cosmological reconstruction for two nonlinear models. We also study in detail a type of the no-go theorem in the framework of this modified teleparallel gravity.
Astrophysical black holes in screened modified gravity
Davis, Anne-Christine; Jha, Rahul; Muir, Jessica; Gregory, Ruth E-mail: r.a.w.gregory@durham.ac.uk E-mail: jlmuir@umich.edu
2014-08-01
Chameleon, environmentally dependent dilaton, and symmetron gravity are three models of modified gravity in which the effects of the additional scalar degree of freedom are screened in dense environments. They have been extensively studied in laboratory, cosmological, and astrophysical contexts. In this paper, we present a preliminary investigation into whether additional constraints can be provided by studying these scalar fields around black holes. By looking at the properties of a static, spherically symmetric black hole, we find that the presence of a non-uniform matter distribution induces a non-constant scalar profile in chameleon and dilaton, but not necessarily symmetron gravity. An order of magnitude estimate shows that the effects of these profiles on in-falling test particles will be sub-leading compared to gravitational waves and hence observationally challenging to detect.
Differential geometry, Palatini gravity and reduction
Capriotti, S.
2014-01-15
The present article deals with a formulation of the so called (vacuum) Palatini gravity as a general variational principle. In order to accomplish this goal, some geometrical tools related to the geometry of the bundle of connections of the frame bundle LM are used. A generalization of Lagrange-Poincaré reduction scheme to these types of variational problems allows us to relate it with the Einstein-Hilbert variational problem. Relations with some other variational problems for gravity found in the literature are discussed.
Ground Gravity Survey At Baltazor Hot Springs Area (Isherwood...
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(Fig. 2) shows a gravity low within the valley area that presumably is related to low-density Cenozoic sediments. The steep gravity gradient along the east side of the valley...
Ground Gravity Survey At Neal Hot Springs Geothermal Area (Colwell...
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and a nearby absolute gravity benchmark was tied in. Gravity data indicated a high density region in-between lower density regions to the east and west. The high density region...
The inverse-square law and quantum gravity
Nieto, M.M.; Goldman, T.; Hughes, R.J.
1988-01-01
This paper briefly discusses a modification to central potential of gravity when antimatter is involved and the possible existence of quantum gravity and a fifth force of nature. 1 ref. (LSP)
Zero-Gravity Centrifugal Force | GE Global Research
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to create centrifugal force create its on gravity? Example if you were spinning a iron ball in space, just as the earth spins, does the iron ball create its on gravity? scott...
Ultrasonic hydrometer. [Specific gravity of electrolyte
Swoboda, C.A.
1982-03-09
The disclosed ultrasonic hydrometer determines the specific gravity (density) of the electrolyte of a wet battery, such as a lead-acid battery. The hydrometer utilizes a transducer that when excited emits an ultrasonic impulse that traverses through the electrolyte back and forth between spaced sonic surfaces. The transducer detects the returning impulse, and means measures the time t between the initial and returning impulses. Considering the distance d between the spaced sonic surfaces and the measured time t, the sonic velocity V is calculated with the equation V = 2d/t. The hydrometer also utilizes a thermocouple to measure the electrolyte temperature. A hydrometer database correlates three variable parameters including sonic velocity in and temperature and specific gravity of the electrolyte, for temperature values between 0 and 40/sup 0/C and for specific gravity values between 1.05 and 1.30. Upon knowing two parameters (the calculated sonic velocity and the measured temperature), the third parameter (specific gravity) can be uniquely found in the database. The hydrometer utilizes a microprocessor for data storage and manipulation.
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Modifying gravity with the aether: An alternative to dark matter
Zlosnik, T. G; Ferreira, P. G; Starkman, G. D.
2007-02-15
There is evidence that Newton and Einstein's theories of gravity cannot explain the dynamics of a universe made up solely of baryons and radiation. To be able to understand the properties of galaxies, clusters of galaxies and the universe on the whole it has become commonplace to invoke the presence of dark matter. An alternative approach is to modify the gravitational field equations to accommodate observations. We propose a new class of gravitational theories in which we add a new degree of freedom, the Aether, in the form of a vector field that is coupled covariantly, but nonminimally, with the space-time metric. We explore the Newtonian and non-Newtonian limits, discuss the conditions for these theories to be consistent and explore their effect on cosmology.
Infrared lessons for ultraviolet gravity: the case of massive gravity and Born-Infeld
JimĂ©nez, Jose BeltrĂˇn; Heisenberg, Lavinia; Olmo, Gonzalo J. E-mail: Lavinia.Heisenberg@unige.ch
2014-11-01
We generalize the ultraviolet sector of gravitation via a Born-Infeld action using lessons from massive gravity. The theory contains all of the elementary symmetric polynomials and is treated in the Palatini formalism. We show how the connection can be solved algebraically to be the Levi-Civita connection of an effective metric. The non-linearity of the algebraic equations yields several branches, one of which always reduces to General Relativity at low curvatures. We explore in detail a minimal version of the theory, for which we study solutions in the presence of a perfect fluid with special attention to the cosmological evolution. In vacuum we recover Ricci-flat solutions, but also an additional physical solution corresponding to an Einstein space. The existence of two physical branches remains for non-vacuum solutions and, in addition, the branch that connects to the Einstein space in vacuum is not very sensitive to the specific value of the energy density. For the branch that connects to the General Relativity limit we generically find three behaviours for the Hubble function depending on the equation of state of the fluid, namely: either there is a maximum value for the energy density that connects continuously with vacuum, or the energy density can be arbitrarily large but the Hubble function saturates and remains constant at high energy densities, or the energy density is unbounded and the Hubble function grows faster than in General Relativity. The second case is particularly interesting because it could offer an interesting inflationary epoch even in the presence of a dust component. Finally, we discuss the possibility of avoiding certain types of singularities within the minimal model.
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Constraints on Covariant Horava-Lifshitz Gravity from frame-dragging experiment
Radicella, Ninfa; Lambiase, Gaetano; Parisi, Luca; Vilasi, Gaetano E-mail: lambiase@sa.infn.it E-mail: vilasi@sa.infn.it
2014-12-01
The effects of Horava-Lifshitz corrections to the gravito-magnetic field are analyzed. Solutions in the weak field, slow motion limit, referring to the motion of a satellite around the Earth are considered. The post-newtonian paradigm is used to evaluate constraints on the Horava-Lifshitz parameter space from current satellite and terrestrial experiments data. In particular, we focus on GRAVITY PROBE B, LAGEOS and the more recent LARES mission, as well as a forthcoming terrestrial project, GINGER.
Spherical collapse in Galileon gravity: fifth force solutions, halo mass function and halo bias
Barreira, Alexandre; Li, Baojiu; Baugh, Carlton M.; Pascoli, Silvia E-mail: liqb@mail.ihep.ac.cn E-mail: silvia.pascoli@durham.ac.uk
2013-11-01
We study spherical collapse in the Quartic and Quintic Covariant Galileon gravity models within the framework of the excursion set formalism. We derive the nonlinear spherically symmetric equations in the quasi-static and weak-field limits, focusing on model parameters that fit current CMB, SNIa and BAO data. We demonstrate that the equations of the Quintic model do not admit physical solutions of the fifth force in high density regions, which prevents the study of structure formation in this model. For the Quartic model, we show that the effective gravitational strength deviates from the standard value at late times (z?<1), becoming larger if the density is low, but smaller if the density is high. This shows that the Vainshtein mechanism at high densities is not enough to screen all of the modifications of gravity. This makes halos that collapse at z?<1 feel an overall weaker gravity, which suppresses halo formation. However, the matter density in the Quartic model is higher than in standard ?CDM, which boosts structure formation and dominates over the effect of the weaker gravity. In the Quartic model there is a significant overabundance of high-mass halos relative to ?CDM. Dark matter halos are also less biased than in ?CDM, with the difference increasing appreciably with halo mass. However, our results suggest that the bias may not be small enough to fully reconcile the predicted matter power spectrum with LRG clustering data.
Junction conditions in extended Teleparallel gravities
De la Cruz-Dombriz, Álvaro; Dunsby, Peter K.S.; Sáez-Gómez, Diego E-mail: peter.dunsby@uct.ac.za
2014-12-01
In the context of extended Teleparallel gravity theories, we address the issue of junction conditions required to guarantee the correct matching of different regions of spacetime. In the absence of shells/branes, these conditions turn out to be more restrictive than their counterparts in General Relativity as in other extended theories of gravity. In fact, the general junction conditions on the matching hypersurfaces depend on the underlying theory and a new condition on the induced tetrads in order to avoid delta-like distributions in the field equations. This result imposes strict consequences on the viability of standard solutions such as the Einstein-Straus-like construction. We find that the continuity of the scalar torsion is required in order to recover the usual General Relativity results.
Twisted covariant noncommutative self-dual gravity
Estrada-Jimenez, S.; Garcia-Compean, H.; Obregon, O.; Ramirez, C.
2008-12-15
A twisted covariant formulation of noncommutative self-dual gravity is presented. The formulation for constructing twisted noncommutative Yang-Mills theories is used. It is shown that the noncommutative torsion is solved at any order of the {theta} expansion in terms of the tetrad and some extra fields of the theory. In the process the first order expansion in {theta} for the Plebanski action is explicitly obtained.
Regulation of flexible arms under gravity
De Luca, A.; Siciliano, B.
1993-08-01
A simple controller is presented for the regulation problem of robot arms with flexible links under gravity. It consists of a joint PD feedback plus a constant feedforward. Global asymptotic stability of the reference equilibrium state is shown under a structural assumption about link elasticity and a mild condition on the proportional gain. The result holds also in the absence of internal damping of the flexible arm. A numerical case study is presented.
Gravity controlled anti-reverse rotation device
Dickinson, Robert J.; Wetherill, Todd M.
1983-01-01
A gravity assisted anti-reverse rotation device for preventing reverse rotation of pumps and the like. A horizontally mounted pawl is disposed to mesh with a fixed ratchet preventing reverse rotation when the pawl is advanced into intercourse with the ratchet by a vertically mounted lever having a lumped mass. Gravitation action on the lumped mass urges the pawl into mesh with the ratchet, while centrifugal force on the lumped mass during forward, allowed rotation retracts the pawl away from the ratchet.
Neutron stars as laboratories for gravity physics
Deliduman, Cemsinan
2014-01-01
We study the structure of neutron stars in R+?R˛ gravity model with perturbative method. We obtain mass-radius relations for four representative equations of state (EoS). We find that, for |?|~10? cm˛, the results differ substantially from the results of general relativity. The effects of modified gravity are seen as mimicking a stiff or soft EoS for neutron stars depending upon whether ? is negative or positive, respectively. Some of the soft EoS that are excluded within the framework of general relativity can be reconciled for certain values of ? of this order with the 2 solar mass neutron star recently observed. Indeed, if the EoS is ever established to be soft, modified gravity of the sort studied here may be required to explain neutron star masses as large as 2 M{sub ?}. The associated length scale ?(?)~10? cm is of the order of the the typical radius of neutron stars implying that this is the smallest value we could find by using neutron stars as a probe. We thus conclude that the true value of ? is most likely much smaller than 10? cm˛.
Severson, Wayne J.
1976-01-01
The overflow line for the reactor vessel of a liquid-metal-cooled nuclear reactor includes means for establishing and maintaining a continuous bleed flow of coolant amounting to 5 to 10% of the total coolant flow through the overflow line to prevent thermal shock to the overflow line when the reactor is restarted following a trip. Preferably a tube is disposed concentrically just inside the overflow line extending from a point just inside the reactor vessel to an overflow tank and a suction line is provided opening into the body of liquid metal in the reactor vessel and into the annulus between the overflow line and the inner tube.
Avelino, P.P.
2012-11-01
In this paper we investigate the classical non-relativistic limit of the Eddington-inspired Born-Infeld theory of gravity. We show that strong bounds on the value of the only additional parameter of the theory Îş, with respect to general relativity, may be obtained by requiring that gravity plays a subdominant role compared to electromagnetic interactions inside atomic nuclei. We also discuss the validity of the continuous fluid approximation used in this and other astrophysical and cosmological studies. We argue that although the continuous fluid approximation is expected to be valid in the case of sufficiently smooth density distributions, its use should eventually be validated at a quantum level.
Can f(T) gravity theories mimic ?CDM cosmic history
Setare, M.R.; Mohammadipour, N. E-mail: N.Mohammadipour@uok.ac.ir
2013-01-01
Recently the teleparallel Lagrangian density described by the torsion scalar T has been extended to a function of T. The f(T) modified teleparallel gravity has been proposed as the natural gravitational alternative for dark energy to explain the late time acceleration of the universe. In order to reconstruct the function f(T) by demanding a background ?CDM cosmology we assume that, (i) the background cosmic history provided by the flat ?CDM (the radiation ere with ?{sub eff} = (1/3), matter and de Sitter eras with ?{sub eff} = 0 and ?{sub eff} = ?1, respectively) (ii) the radiation dominate in the radiation era with ?{sub 0r} = 1 and the matter dominate during the matter phases when ?{sub 0m} = 1. We find the cosmological dynamical system which can obey the ?CDM cosmic history. In each era, we find a critical lines that, the radiation dominated and the matter dominated are one points of them in the radiation and matter phases, respectively. Also, we drive the cosmologically viability condition for these models. We investigate the stability condition with respect to the homogeneous scalar perturbations in each era and we obtain the stability conditions for the fixed points in each eras. Finally, we reconstruct the function f(T) which mimics cosmic expansion history.
Gravity Survey of the Carson Sink - Data and Maps
Faulds, James E.
2013-12-31
A detailed gravity survey was carried out for the entire Carson Sink in western Nevada (Figure 1) through a subcontract to Zonge Engineering, Inc. The Carson Sink is a large composite basin containing three known, blind highâ€temperature geothermal systems (Fallon Airbase, Stillwater, and Soda Lake). This area was chosen for a detailed gravity survey in order to characterize the gravity signature of the known geothermal systems and to identify other potential blind systems based on the structural setting indicated by the gravity data. Data: Data were acquired at approximately 400, 800, and 1600 meter intervals for a total of 1,243 stations. The project location and station location points are presented in Figure 14. The station distribution for this survey was designed to complete regional gravity coverage in the Carson Sink area without duplication of available public and private gravity coverage. Gravity data were acquired using a Scintrex CGâ€5 gravimeter and a LaCoste and Romberg (L&R) Modelâ€G gravimeter. The CGâ€5 gravity meter has a reading resolution of 0.001 milligals and a typical repeatability of less than 0.005 milligals. The L&R gravity meter has a reading resolution of 0.01 milligals and a typical repeatability of 0.02 milligals. The basic processing of gravimeter readings to calculate through to the Complete Bouguer Anomaly was made using the Gravity and Terrain Correction software version 7.1 for Oasis Montaj by Geosoft LTD. Results: The gravity survey of the Carson Sink yielded the following products. Project location and station location map (Figure 14). Complete Bouguer Anomaly @ 2.67 gm/cc reduction density. Gravity Complete Bouguer Anomaly at 2.50 g/cc Contour Map (Figure 15). Gravity Horizontal Gradient Magnitude Shaded Color Contour Map. Gravity 1st Vertical Derivative Color Contour Map. Interpreted Depth to Mesozoic Basement (Figure 16), incorporating drillâ€hole intercept values. Preliminary Interpretation of Results: The Carson Sink
Ground Gravity Survey At Under Steamboat Springs Area (Warpinski...
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Ground Gravity Survey Activity Date Usefulness useful DOE-funding Unknown Notes Update to Warpinski, et al., 2002 References N. R. Warpinski, A. R. Sattler, R. Fortuna, D....
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Chocolate Mountains Area (Alm, Et Al., 2010) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At Chocolate Mountains Area...
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search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At Blue Mountain Geothermal Area (Fairbank Engineering Ltd, 2003) Exploration Activity Details...
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Apps Datasets Community Login | Sign Up Search Category Edit History Category:Ground Gravity Survey Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home...
Lorentz Invariant phenomenological model of quantum gravity: A minimalistic presentation
Bonder, Yuri
2012-08-24
The purpose of this paper is to give a minimalistic and self-contained presentation of a Lorentz Invariant phenomenological model of Quantum Gravity.
Ground Gravity Survey At Rio Grande Rift Region (Aiken & Ander...
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DOE-funding Unknown References Carlos L.V. Aiken, Mark E. Ander (1981) A Regional Strategy For Geothermal Exploration With Emphasis On Gravity And Magnetotellurics Additional...
Ground Gravity Survey At Walker Lake Valley Area (Shoffner, Et...
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N. Hinz, A. Sabin, M. Lazaro, S. Alm (2010) Understanding Fault Characteristics And Sediment Depth For Geothermal Exploration Using 3D Gravity Inversion In Walker Valley, Nevada...
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Three-dimensional gravity modeling and focusing inversion using...
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Using synthetic data from models of varying complexity and a field data set, it is demonstrated that, given an adequate depth weighting function, the gravity inversion in the ...
A gravity model for the Coso geothermal area, California | Open...
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Most of the gravity variations can be explained by two lithologic units: (1) low density wedges of Quarternary alluvium with interbedded thin basalts (2.4 gcmsup 3)...
Ground Gravity Survey At Kilauea East Rift Geothermal Area (Leslie...
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of the seaward extension of the ERZ. Gravity measurements of Puna Ridge show a high density anomaly at depth which corresponds to high velocity data obtained from seismic...
Ground Gravity Survey (Nannini, 1986) | Open Energy Information
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depth inside the sedimentary formations of the basement and often present a negative density contrast when compared to the latter. Gravity could help to identify these bodies by...
Bouguer gravity anomalies, depth to bedrock, and shallow temperature...
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Bouguer gravity anomalies, depth to bedrock, and shallow temperature in the Humboldt House geothermal area, Pershing County, Nevada Jump to: navigation, search OpenEI Reference...
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search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At Raft River Geothermal Area (1978) Exploration Activity Details Location Raft River...
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(1990) Exploration Activity Details Location Coso Geothermal Area Exploration Technique Ground Gravity Survey Activity Date 1990 Usefulness not indicated DOE-funding Unknown...
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2004) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At Truckhaven Area (Warpinski, Et Al., 2004) Exploration Activity...
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Exploration Activity Details Location Lake City Hot Springs Area Exploration Technique Ground Gravity Survey Activity Date Usefulness not indicated DOE-funding Unknown Notes The...
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Francisco Volcanic Field Area (Warpinski, Et Al., 2004) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At San Francisco...
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Finally, the gravity survey also shows anomalies that correlate with the seismic and microseismic data. All of these results will be integrated to obtain the most probable...
Ground Gravity Survey At Lightning Dock Geothermal Area (Swanberg...
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Basis Examination of geothermal resources of New Mexico Notes detailed gravity and magnetics survey of Lightning Dock to identify burried structures as a source of the thermal...
Ground Gravity Survey At Roosevelt Hot Springs Geothermal Area...
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Unknown Exploration Basis Faulder 1991 Conceptual Geological Model compilation and literature review of the Roosevelt Hot Springs Geothermal Area. Notes Gravity modeling and...
Deporcel, Lilian
2001-04-02
The XXVI SLAC Summer Institute on Particle Physics was held from August 3 to August 14, 1998. The topic, ''Gravity--from the Hubble Length to the Planck Length,'' brought together 179 physicists from 13 countries. The lectures in this volume cover the seven-day school portion of the Institute, which took us from the largest scales of the cosmos, to the Planck length at which gravity might be unified with the other forces of nature. Lectures by Robert Wagoner, Clifford Will, and Lynn Cominsky explored the embedding of gravity into general relativity and the confrontation of this idea with experiments in the laboratory and astrophysical settings. Avishai Deckel discussed observations and implications of the large-scale structure of the universe, and Tony Tyson presented the gravitational lensing effect and its use in the ongoing search for signatures of the unseen matter of the cosmos. The hunt for the wave nature of gravity was presented by Sam Finn and Peter Saulson, and Joe Polchinski showed us what gravity might look like in the quantum limit at the Planck scale. The lectures were followed by afternoon discussion sessions, where students could further pursue questions and topics with the day's lecturers. The Institute concluded with a three-day topical conference covering recent developments in theory and experiment from around the world of elementary particle physics and cosmology; its proceedings are also presented in this volume.
Testing chameleon gravity with the Coma cluster
Terukina, Ayumu; Yamamoto, Kazuhiro; Lombriser, Lucas; Bacon, David; Koyama, Kazuya; Nichol, Robert C. E-mail: lucas.lombriser@port.ac.uk E-mail: david.bacon@port.ac.uk E-mail: bob.nichol@port.ac.uk
2014-04-01
We propose a novel method to test the gravitational interactions in the outskirts of galaxy clusters. When gravity is modified, this is typically accompanied by the introduction of an additional scalar degree of freedom, which mediates an attractive fifth force. The presence of an extra gravitational coupling, however, is tightly constrained by local measurements. In chameleon modifications of gravity, local tests can be evaded by employing a screening mechanism that suppresses the fifth force in dense environments. While the chameleon field may be screened in the interior of the cluster, its outer region can still be affected by the extra force, introducing a deviation between the hydrostatic and lensing mass of the cluster. Thus, the chameleon modification can be tested by combining the gas and lensing measurements of the cluster. We demonstrate the operability of our method with the Coma cluster, for which both a lensing measurement and gas observations from the X-ray surface brightness, the X-ray temperature, and the Sunyaev-Zel'dovich effect are available. Using the joint observational data set, we perform a Markov chain Monte Carlo analysis of the parameter space describing the different profiles in both the Newtonian and chameleon scenarios. We report competitive constraints on the chameleon field amplitude and its coupling strength to matter. In the case of f(R) gravity, corresponding to a specific choice of the coupling, we find an upper bound on the background field amplitude of |f{sub R0}| < 6 × 10{sup ?5}, which is currently the tightest constraint on cosmological scales.
Ostrogradski Hamiltonian approach for geodetic brane gravity
Cordero, Ruben; Molgado, Alberto
2010-12-07
We present an alternative Hamiltonian description of a branelike universe immersed in a flat background spacetime. This model is named geodetic brane gravity. We set up the Regge-Teitelboim model to describe our Universe where such field theory is originally thought as a second order derivative theory. We refer to an Ostrogradski Hamiltonian formalism to prepare the system to its quantization. This approach comprize the manage of both first- and second-class constraints and the counting of degrees of freedom follows accordingly.
Coordinate time dependence in quantum gravity
Bojowald, Martin; Singh, Parampreet; Skirzewski, Aureliano
2004-12-15
The intuitive classical space-time picture breaks down in quantum gravity, which makes a comparison and the development of semiclassical techniques quite complicated. Using ingredients of the group averaging method to solve constraints one can nevertheless introduce a classical coordinate time into the quantum theory, and use it to investigate the way a semiclassical continuous description emerges from discrete quantum evolution. Applying this technique to test effective classical equations of loop cosmology and their implications for inflation and bounces, we show that the effective semiclassical theory is in good agreement with the quantum description even at short scales.
Low gravity fluid-thermal experiments
Krotiuk, W.J.; Cuta, J.M.
1987-06-01
Pacific Northwest Laboratory (PNL) is the lead laboratory for the thermal-hydraulic research in the US Department of Energy Multimegawatt Space Nuclear Power Program. PNL must provide the tools necessary to analyze proposed space reactor concepts, which include single- and two-phase alkali metal and gas-cooled designs. PNL has divided its activities for this task into three basic areas: computer code development, thermal-hydraulic modeling, and experimentation. The subject of this paper is the low-gravity experimental program currently underway at PNL in support of the MMW Program.
Dualities of 3D dilaton gravity
Cadoni, M. |
1996-12-01
We investigate Brans-Dicke dilaton gravity theories in 2+1 dimensions. We show that the reduced field equations for solutions with a diagonal metric and depending only on one spacetime coordinate have a continuous O(2) symmetry. Using this symmetry we derive general static and cosmological solutions of the theory. The action of the discrete group O(2,{bold Z}) on the space of the solutions is discussed. Three-dimensional string effective theory and three-dimensional general relativity are discussed in detail. In particular, we find that the previously discovered black string solution is dual to a spacetime with a conical singularity. {copyright} {ital 1996 The American Physical Society.}
Harko, Tiberiu; Lobo, Francisco S.N.; Otalora, G.; Saridakis, Emmanuel N. E-mail: flobo@cii.fc.ul.pt
2014-12-01
We present an extension of f(T) gravity, allowing for a general coupling of the torsion scalar T with the trace of the matter energy-momentum tensor T. The resulting f(T,T) theory is a new modified gravity, since it is different from all the existing torsion or curvature based constructions. Applied to a cosmological framework, it leads to interesting phenomenology. In particular, one can obtain a unified description of the initial inflationary phase, the subsequent non-accelerating, matter-dominated expansion, and then the transition to a late-time accelerating phase. Additionally, the effective dark energy sector can be quintessence or phantom-like, or exhibit the phantom-divide crossing during the evolution. Moreover, in the far future the universe results either to a de Sitter exponential expansion, or to eternal power-law accelerated expansions. Finally, a detailed study of the scalar perturbations at the linear level reveals that f(T,T) cosmology can be free of ghosts and instabilities for a wide class of ansatzes and model parameters.
A dynamical inconsistency of Horava gravity
Henneaux, Marc; Kleinschmidt, Axel; Lucena Gomez, Gustavo
2010-03-15
The dynamical consistency of the nonprojectable version of Horava gravity is investigated by focusing on the asymptotically flat case. It is argued that for generic solutions of the constraint equations the lapse must vanish asymptotically. We then consider particular values of the coupling constants for which the equations are tractable and in that case we prove that the lapse must vanish everywhere--and not only at infinity. Put differently, the Hamiltonian constraints are generically all second-class. We then argue that the same feature holds for generic values of the couplings, thus revealing a physical inconsistency of the theory. In order to cure this pathology, one might want to introduce further constraints but the resulting theory would then lose much of the appeal of the original proposal by Horava. We also show that there is no contradiction with the time-reparametrization invariance of the action, as this invariance is shown to be a so-called 'trivial gauge symmetry' in Horava gravity, hence with no associated first-class constraints.
Disformal transformations, veiled General Relativity and Mimetic Gravity
Deruelle, Nathalie; Rua, Josephine E-mail: rua@cbpf.br
2014-09-01
In this Note we show that Einstein's equations for gravity are generically invariant under ''disformations''. We also show that the particular subclass when this is not true yields the equations of motion of ''Mimetic Gravity''. Finally we give the ''mimetic'' generalization of the Schwarzschild solution.
Bimetric gravity doubly coupled to matter: theory and cosmological implications
Akrami, Yashar; Koivisto, Tomi S.; Mota, David F.; Sandstad, Marit E-mail: t.s.koivisto@astro.uio.no E-mail: marit.sandstad@astro.uio.no
2013-10-01
A ghost-free theory of gravity with two dynamical metrics both coupled to matter is shown to be consistent and viable. Its cosmological implications are studied, and the models, in particular in the context of partially massless gravity, are found to explain the cosmic acceleration without resorting to dark energy.
Two-phase alkali-metal experiments in reduced gravity
Antoniak, Z.I.
1986-06-01
Future space missions envision the use of large nuclear reactors utilizing either a single or a two-phase alkali-metal working fluid. The design and analysis of such reactors require state-of-the-art computer codes that can properly treat alkali-metal flow and heat transfer in a reduced-gravity environment. A literature search of relevant experiments in reduced gravity is reported on here, and reveals a paucity of data for such correlations. The few ongoing experiments in reduced gravity are noted. General plans are put forth for the reduced-gravity experiments which will have to be performed, at NASA facilities, with benign fluids. A similar situation exists regarding two-phase alkali-metal flow and heat transfer, even in normal gravity. Existing data are conflicting and indequate for the task of modeling a space reactor using a two-phase alkali-metal coolant. The major features of past experiments are described here. Data from the reduced-gravity experiments with innocuous fluids are to be combined with normal gravity data from the two-phase alkali-metal experiments. Analyses undertaken here give every expectation that the correlations developed from this data base will provide a valid representation of alkali-metal heat transfer and pressure drop in reduced gravity.
Series Transmission Line Transformer
Buckles, Robert A.; Booth, Rex; Yen, Boris T.
2004-06-29
A series transmission line transformer is set forth which includes two or more of impedance matched sets of at least two transmissions lines such as shielded cables, connected in parallel at one end ans series at the other in a cascading fashion. The cables are wound about a magnetic core. The series transmission line transformer (STLT) which can provide for higher impedance ratios and bandwidths, which is scalable, and which is of simpler design and construction.
Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)
MMW Drilling & Lining PI & Presenter: Ken Oglesby Impact Technologies LLC SubRecipient: MIT- Dr.Woskov, Dr.Einstein Research & Development Track Project Officers: Ava Coy & Erik ...
U.S. Department of Energy (DOE) - all webpages (Extended Search)
Transmission Business Line Non-Federal Financing of Transmission Projects - March 2004 Critical paths on the Northwest transmission grid are congested and the system is near or at...
Massive gravitational waves in Chern-Simons modified gravity
Myung, Yun Soo; Moon, Taeyoon E-mail: tymoon@inje.ac.kr
2014-10-01
We consider the nondynamical Chern-Simons (nCS) modified gravity, which is regarded as a parity-odd theory of massive gravity in four dimensions. We first find polarization modes of gravitational waves for Î¸=x/ÎĽ in nCS modified gravity by using the Newman-Penrose formalism where the null complex tetrad is necessary to specify gravitational waves. We show that in the Newmanâ€“Penrose formalism, the number of polarization modes is one in addition to an unspecified Î¨{sub 4}, implying three degrees of freedom for Î¸=x/ÎĽ. This compares with two for a canonical embedding of Î¸=t/ÎĽ. Also, if one introduces the Ricci tensor formalism to describe a massive graviton arising from the nCS modified gravity, one finds one massive mode after making second-order wave equations, which is compared to five found from the parity-even Einsteinâ€“Weyl gravity.
Plains and Eastern Clean Line Transmission Line: Comment from Marshall
Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)
Hughes | Department of Energy from Marshall Hughes Plains and Eastern Clean Line Transmission Line: Comment from Marshall Hughes Comment submitted on updated Part 2 application. Comment from Marshall Hughes 07-10-15.pdf (14.91 KB) More Documents & Publications Plains and Eastern Clean Line Transmission Line: Comment from Mr. Dyer Plains and Eastern Clean Line Transmission Line: Comment from Sheila Beck Plains and Eastern Clean Line Transmission Line: Comment from Patti McCutchen
Ground Gravity Survey At Glass Buttes Area (DOE GTP) | Open Energy...
OpenEI (Open Energy Information) [EERE & EIA]
Ground Gravity Survey At Glass Buttes Area (DOE GTP) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At Glass Buttes Area...
Ground Gravity Survey At Cove Fort Area (Warpinski, Et Al., 2002...
OpenEI (Open Energy Information) [EERE & EIA]
Ground Gravity Survey At Cove Fort Area (Warpinski, Et Al., 2002) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At Cove...
Ground Gravity Survey At Hot Pot Area (DOE GTP) | Open Energy...
OpenEI (Open Energy Information) [EERE & EIA]
Ground Gravity Survey At Hot Pot Area (DOE GTP) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At Hot Pot Area (DOE GTP)...
Ground Gravity Survey At Fort Bliss Area (DOE GTP) | Open Energy...
OpenEI (Open Energy Information) [EERE & EIA]
Ground Gravity Survey At Fort Bliss Area (DOE GTP) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At Fort Bliss Area (DOE...
Ground Gravity Survey At New River Area (DOE GTP) | Open Energy...
OpenEI (Open Energy Information) [EERE & EIA]
Ground Gravity Survey At New River Area (DOE GTP) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At New River Area (DOE...
Transmission Line Security Monitor
None
2016-07-12
The Transmission Line Security Monitor is a multi-sensor monitor that mounts directly on high-voltage transmission lines to detect, characterize and communicate terrorist activity, human tampering and threatening conditions around support towers. For more information about INL's critical infrastructure protection research, visit http://www.facebook.com/idahonationallaboratory.
Transmission Line Security Monitor
2011-01-01
The Transmission Line Security Monitor is a multi-sensor monitor that mounts directly on high-voltage transmission lines to detect, characterize and communicate terrorist activity, human tampering and threatening conditions around support towers. For more information about INL's critical infrastructure protection research, visit http://www.facebook.com/idahonationallaboratory.
Mass gap for gravity localized on Weyl thick branes
Barbosa-Cendejas, N.; Santos, M. A. Reyes; Herrera-Aguilar, A.; Schubert, C.
2008-06-15
We consider thick brane configurations in a pure geometric Weyl integrable 5D space-time, a non-Riemannian generalization of Kaluza-Klein (KK) theory involving a geometric scalar field. Thus, the 5D theory describes gravity coupled to a self-interacting scalar field which gives rise to the structure of the thick branes. We continue the study of the properties of a previously found family of solutions which is smooth at the position of the brane but involves naked singularities in the fifth dimension. Analyzing their graviton spectrum, we find that a particularly interesting situation arises for a special case in which the 4D graviton is separated from the KK gravitons by a mass gap. The corresponding effective Schroedinger equation has a modified Poeschl-Teller potential and can be solved exactly. Apart from the massless 4D graviton, it contains one massive KK bound state, and the continuum spectrum of delocalized KK modes. We also discuss the mass hierarchy problem, and explicitly compute the corrections to Newton's law in the thin brane limit.
Asymptotically flat radiating solutions in third order Lovelock gravity
Dehghani, M. H.; Farhangkhah, N.
2008-09-15
In this paper, we present an exact spherically symmetric solution of third order Lovelock gravity in n dimensions which describes the gravitational collapse of a null dust fluid. This solution is asymptotically (anti-)de Sitter or flat depending on the choice of the cosmological constant. Using the asymptotically flat solution for n{>=}7 with a power-law form of the mass as a function of the null coordinate, we present a model for a gravitational collapse in which a null dust fluid radially injects into an initially flat and empty region. It is found that a naked singularity is inevitably formed whose strength is different for the n=7 and n{>=}8 cases. In the n=7 case, the limiting focusing condition for the strength of curvature singularity is satisfied. But for n{>=}8, the strength of curvature singularity depends on the rate of increase of mass of the spacetime. These considerations show that the third order Lovelock term weakens the strength of the curvature singularity.
Mixing lengths scaling in a gravity flow
Ecke, Robert E [Los Alamos National Laboratory; Rivera, Micheal [Los Alamos National Laboratory; Chen, Jun [Los Alamos National Laboratory; Ecke, Robert E [Los Alamos National Laboratory
2009-01-01
We present an experimental study of the mixing processes in a gravity current. The turbulent transport of momentum and buoyancy can be described in a very direct and compact form by a Prandtl mixing length model [1]: the turbulent vertical fluxes of momentum and buoyancy are found to scale quadraticatly with the vertical mean gradients of velocity and density. The scaling coefficient is the square of the mixing length, approximately constant over the mixing zone of the stratified shear layer. We show in this paper how, in different flow configurations, this length can be related to the shear length of the flow {radical}({var_epsilon}/{partial_derivative}{sub z}u{sup 3}).
Semiclassical approximation to supersymmetric quantum gravity
Kiefer, Claus; Lueck, Tobias; Moniz, Paulo
2005-08-15
We develop a semiclassical approximation scheme for the constraint equations of supersymmetric canonical quantum gravity. This is achieved by a Born-Oppenheimer type of expansion, in analogy to the case of the usual Wheeler-DeWitt equation. The formalism is only consistent if the states at each order depend on the gravitino field. We recover at consecutive orders the Hamilton-Jacobi equation, the functional Schroedinger equation, and quantum gravitational correction terms to this Schroedinger equation. In particular, the following consequences are found: (i) the Hamilton-Jacobi equation and therefore the background spacetime must involve the gravitino, (ii) a (many-fingered) local time parameter has to be present on super Riem {sigma} (the space of all possible tetrad and gravitino fields) (iii) quantum supersymmetric gravitational corrections affect the evolution of the very early Universe. The physical meaning of these equations and results, in particular, the similarities to and differences from the pure bosonic case, are discussed.
Testing quantum gravity via cosmogenic neutrino oscillations
Christian, Joy
2005-01-15
Implications of some proposed theories of quantum gravity for neutrino flavor oscillations are explored within the context of modified dispersion relations of special relativity. In particular, approximate expressions for Planck scale-induced deviations from the standard oscillation length are obtained as functions of neutrino mass, energy, and propagation distance. Grounding on these expressions, it is pointed out that, in general, even those deviations that are suppressed by the second power of the Planck energy may be observable for ultra-high-energy neutrinos, provided they originate at cosmological distances. In fact, for neutrinos in the highest energy range of EeV to ZeV, deviations that are suppressed by as much as the seventh power of the Planck energy may become observable. Accordingly, realistic possibilities of experimentally verifying these deviations by means of the next generation neutrino detectors--such as IceCube and ANITA--are investigated.
High-Accuracy Measurements of the Centre of Gravity of Avalanches in Proportional Chambers
Charpak, G.; Jeavons, A.; Sauli, F.; Stubbs, R.
1973-09-24
In a multiwire proportional chamber the avalanches occur close to the anode wires. The motion of the positive ions in the large electric fields at the vicinity of the wires induces fast-rising positive pulses on the surrounding electrodes. Different methods have been developed in order to determine the position of the centre of the avalanches. In the method we describe, the centre of gravity of the pulse distribution is measured directly. It seems to lead to an accuracy which is limited only by the stability of the spatial distribution of the avalanches generated by the process being measured.
Nicholls, Colin I.
1992-07-14
An on-line product sampling apparatus and method for measuring product samples from a product stream (12) in a flow line (14) having a sampling aperture (11), includes a sampling tube (18) for containing product samples removed from flow line (14). A piston (22) removes product samples from the product stream (12) through the sampling aperture (11) and returns samples to product stream (12). A sensor (20) communicates with sample tube (18), and senses physical properties of samples while the samples are within sample tube (18). In one embodiment, sensor (20) comprises a hydrogen transient nuclear magnetic resonance sensor for measuring physical properties of hydrogen molecules.
Coherent soliton communication lines
Yushko, O. V. Redyuk, A. A.; Fedoruk, M. P.; Turitsyn, S. K.
2014-11-15
The data transmission in coherent fiber-optical communication lines using solitons with a variable phase is studied. It is shown that nonlinear coherent structures (solitons) can be applied for effective signal transmission over a long distance using amplitude and optical-phase keying of information. The optimum ratio of the pulse width to the bit slot at which the spectral efficiency (transmitted bits per second and hertz) is maximal is determined. It is shown that soliton fiber-optical communication lines can ensure data transmission at a higher spectral efficiency as compared to traditional communication lines and at a high signal-to-noise ratio.
Primordial massive gravitational waves from Einstein-Chern-Simons-Weyl gravity
Myung, Yun Soo; Moon, Taeyoon E-mail: tymoon@inje.ac.kr
2014-08-01
We investigate the evolution of cosmological perturbations during de Sitter inflation in the Einstein-Chern-Simons-Weyl gravity. Primordial massive gravitational waves are composed of one scalar, two vector and four tensor circularly polarized modes. We show that the vector power spectrum decays quickly like a transversely massive vector in the superhorizon limit zÂ â†’Â 0. In this limit, the power spectrum coming from massive tensor modes decays quickly, leading to the conventional tensor power spectrum. Also, we find that in the limit of m{sup 2}Â â†’Â 0 (keeping the Weyl-squared term only), the vector and tensor power spectra disappear. It implies that their power spectra are not gravitationally produced because they (vector and tensor) are decoupled from the expanding de Sitter background, as a result of conformal invariance.
Open Wilson lines and chiral condensates in thermal holographic QCD
Argyres, Philip C.; Edalati, Mohammad; Leigh, Robert G.; Vazquez-Poritz, Justin F.
2009-02-15
We investigate various aspects of a proposal by Aharony and Kutasov [O. Aharony and D. Kutasov, Phys. Rev. D 78, 026005 (2008).] for the gravity dual of an open Wilson line in the Sakai-Sugimoto model or its noncompact version. In particular, we use their proposal to determine the effect of finite temperature, as well as background electric and magnetic fields, on the chiral symmetry breaking order parameter. We also generalize their prescription to more complicated worldsheets and identify the operators dual to such worldsheets.
There are several Lineman (Liveline) positions located in Spokane, Washington. A successful candidate in this position will perform construction and maintenance work for live-line on wood and steel...
The Public Service Board (PSB) of Vermont developed rules regarding utility line extension requests. While the majority of the rules focus on the procedure followed (and associated fees) for the...
National Nuclear Security Administration (NNSA)
Maersk Line containers has an average age of less than six years and a stringent maintenance programme ensures they are always ready for service. Each container in our fleet...
Latorre, V.R.; Watwood, D.B.
1994-09-27
A short-range, radio frequency (RF) transmitting-receiving system that provides both visual and audio warnings to the pilot of a helicopter or light aircraft of an up-coming power transmission line complex. Small, milliwatt-level narrowband transmitters, powered by the transmission line itself, are installed on top of selected transmission line support towers or within existing warning balls, and provide a continuous RF signal to approaching aircraft. The on-board receiver can be either a separate unit or a portion of the existing avionics, and can also share an existing antenna with another airborne system. Upon receipt of a warning signal, the receiver will trigger a visual and an audio alarm to alert the pilot to the potential power line hazard. 4 figs.
Latorre, Victor R.; Watwood, Donald B.
1994-01-01
A short-range, radio frequency (RF) transmitting-receiving system that provides both visual and audio warnings to the pilot of a helicopter or light aircraft of an up-coming power transmission line complex. Small, milliwatt-level narrowband transmitters, powered by the transmission line itself, are installed on top of selected transmission line support towers or within existing warning balls, and provide a continuous RF signal to approaching aircraft. The on-board receiver can be either a separate unit or a portion of the existing avionics, and can also share an existing antenna with another airborne system. Upon receipt of a warning signal, the receiver will trigger a visual and an audio alarm to alert the pilot to the potential power line hazard.
Perihelion precession for modified Newtonian gravity
Schmidt, Hans-Juergen
2008-07-15
We calculate the perihelion precession {delta} for nearly circular orbits in a central potential V(r). Differently from other approaches to this problem, we do not assume that the potential is close to the Newtonian one. The main idea in the deduction is to apply the underlying symmetries of the system to show that {delta} must be a function of r{center_dot}V{sup ''}(r)/V{sup '}(r) and to use the transformation behavior of {delta} in a rotating system of reference. This is equivalent to say that the effective potential can be written in a one-parameter set of possibilities as the sum of centrifugal potential and potential of the central force. We get the following universal formula valid for V{sup '}(r)>0 reading {delta}(r)=2{pi}{center_dot}[(1/{radical}(3+r{center_dot}V{sup ''}(r)/V{sup '}(r)))-1]. It has to be read as follows: a circular orbit at this value r exists and is stable if and only if this {delta} is well-defined as real; and if this is the case, then the angular difference from one perihelion to the next one for nearly circular orbits at this r is exactly 2{pi}+{delta}(r). Then we apply this result to examples of recent interest like modified Newtonian gravity and linearized fourth-order gravity. In the second part of the paper, we generalize this universal formula to static spherically symmetric space-times ds{sup 2}=-e{sup 2{lambda}}{sup (r)}dt{sup 2}+e{sup 2{mu}}{sup (r)}dr{sup 2}+r{sup 2}d{omega}{sup 2}; for orbits near r it reads {delta}=2{pi}{center_dot}[(e{sup {mu}}{sup (r)}/{radical}(3-2r{center_dot}{lambda}{sup '}(r)+r{center_dot}{lambda}{sup ''}(r)/{lambda}{sup '}(r)))-1] and can be applied to a large class of theories. For the Schwarzschild black hole with mass parameter m>0 it leads to {delta}=2{pi}{center_dot}[(1/{radical}(1-(6m/r)))-1], a surprisingly unknown formula. It represents a strict result and is applicable for all values r>6m and is in good agreement with the fact that stable circular orbits exist for r>6m only. For r>>m, one can
Ground Gravity Survey At Cove Fort Area - Vapor (Warpinski, Et...
OpenEI (Open Energy Information) [EERE & EIA]
Ground Gravity Survey Activity Date Usefulness not indicated DOE-funding Unknown Notes Update to Warpinski, et al., 2002 References N. R. Warpinski, A. R. Sattler, R. Fortuna, D....
Ground Gravity Survey At Dixie Valley Geothermal Area (Blackwell...
OpenEI (Open Energy Information) [EERE & EIA]
local studies conducted in the past. Gravity data measured in the 1970's by Hunt Oil, Sun Oil, and Southland royalty (all unpublished reports) ware used. These data were combined...
Ground Gravity Survey At Neal Hot Springs Geothermal Area (U...
OpenEI (Open Energy Information) [EERE & EIA]
survey was completed by MWH Geo-Surveys. Interpretations were made by creating a 3D density inversion map. Gravity and magnetic data were used in siting the first production...
Ground Gravity Survey At Mt Princeton Hot Springs Geothermal...
OpenEI (Open Energy Information) [EERE & EIA]
lithologic distrubtions Notes Gravity low associated with Mt. Princeton Batholith; density contrast of -0.5 gcm3 of valley-fill sediments relative to batholith References J.E....
Geologic interpretation of gravity and magnetic data in the Salida...
OpenEI (Open Energy Information) [EERE & EIA]
interpretation of gravity and magnetic data in the Salida region, Colorado Authors J.E. Case and R.F. Sikora Published U.S. Geological Survey Open-File Report, 1984 Report...
Ground Gravity Survey At Truckhaven Area (Layman Energy Associates...
OpenEI (Open Energy Information) [EERE & EIA]
9. The 95 magnetotelluric (MT) soundings cover a central area of about 80 square kilometers. The 126 gravity stations extend over a broader area of about 150 square kilometers,...
Regional Gravity Survey of the Northern Great Salt Lake Desert...
OpenEI (Open Energy Information) [EERE & EIA]
of about -196 mgal over the alluvium-covered graben areas. The gravity high over the Raft River Mountains apparently corresponds with the Raft River Mountains anticline. A belt...
Ground Gravity Survey At Dixie Valley Geothermal Area (Iovenitti...
OpenEI (Open Energy Information) [EERE & EIA]
project area. These data were used in conjunction with past gravity data reported in by Smith et al (2001) and Blackwell et al (2005). The analysis of these data had not been...
Ionospheric acoustic and gravity waves associated with midlatitude thunderstorms
Lay, Erin H.; Shao, Xuan -Min; Kendrick, Alexander K.; Carrano, Charles S.
2015-07-30
Acoustic waves with periods of 2â€“4 min and gravity waves with periods of 6â€“16 min have been detected at ionospheric heights (25â€“350 km) using GPS total electron content measurements. The area disturbed by these waves and the wave amplitudes have been associated with underlying thunderstorm activity. A statistical study comparing Next Generation Weather Radar thunderstorm measurements with ionospheric acoustic and gravity waves in the midlatitude U.S. Great Plains region was performed for the time period of Mayâ€“July 2005. An increase of ionospheric acoustic wave disturbed area and amplitude is primarily associated with large thunderstorms (mesoscale convective systems). Ionospheric gravity wavemoreÂ Â» disturbed area and amplitude scale with thunderstorm activity, with even small storms (i.e., individual storm cells) producing an increase of gravity waves.Â«Â less
Ionospheric acoustic and gravity waves associated with midlatitude thunderstorms
Lay, Erin H.; Shao, Xuan -Min; Kendrick, Alexander K.; Carrano, Charles S.
2015-07-30
Acoustic waves with periods of 2â€“4 min and gravity waves with periods of 6â€“16 min have been detected at ionospheric heights (25â€“350 km) using GPS total electron content measurements. The area disturbed by these waves and the wave amplitudes have been associated with underlying thunderstorm activity. A statistical study comparing Next Generation Weather Radar thunderstorm measurements with ionospheric acoustic and gravity waves in the midlatitude U.S. Great Plains region was performed for the time period of Mayâ€“July 2005. An increase of ionospheric acoustic wave disturbed area and amplitude is primarily associated with large thunderstorms (mesoscale convective systems). Ionospheric gravity wave disturbed area and amplitude scale with thunderstorm activity, with even small storms (i.e., individual storm cells) producing an increase of gravity waves.
Fault Current Limiters Superconducting & Solid-state Power Equipment Office of Electricity Delivery and Energy Reliability www.oe.energy.gov Office of Electricity Delivery and ...
National Nuclear Security Administration (NNSA)
Detection System (USNDS), which monitors compliance with the international Limited Test Ban Treaty (LTBT). The LTBT, signed by 108 countries, prohibits nuclear testing in the...
Correlations estimate volume distilled using gravity, boiling point
Moreno, A.; Consuelo Perez de Alba, M. del; Manriquez, L.; Guardia Mendoz, P. de la
1995-10-23
Mathematical nd graphic correlations have been developed for estimating cumulative volume distilled as a function of crude API gravity and true boiling point (TBP). The correlations can be used for crudes with gravities of 21--34{degree} API and boiling points of 150--540 C. In distillation predictions for several mexican and Iraqi crude oils, the correlations have exhibited accuracy comparable to that of laboratory measurements. The paper discusses the need for such a correlation and the testing of the correlation.
Two-phase computer codes for zero-gravity applications
Krotiuk, W.J.
1986-10-01
This paper discusses the problems existing in the development of computer codes which can analyze the thermal-hydraulic behavior of two-phase fluids especially in low gravity nuclear reactors. The important phenomenon affecting fluid flow and heat transfer in reduced gravity is discussed. The applicability of using existing computer codes for space applications is assessed. Recommendations regarding the use of existing earth based fluid flow and heat transfer correlations are made and deficiencies in these correlations are identified.
Single line reversing system capsular pneumatic freight pipelines
Weaver, P.B.
1999-07-01
In the 1800's the first Pneumatic Tube Systems sent a carrier vertically from one floor to another in a hospital using a foot-powered bellows. The carrier was returned to the starting point down the same tube using gravity. This was the first Single Line Reversing system. As the stations were moved apart horizontally the foot-powered bellows at both ends became ineffective and were replaced with a single blower or exhauster. The blower/exhauster ran continuously therefore a second line for returning carriers to the starting point, had to be installed - hence Twin Line systems. These systems were used for transporting mail, paperwork, medications, steel mill samples, parts, tools, medical lab samples, etc., in hospitals, stores and other businesses. Twin Line systems were very popular until about 1970 at which time installation labor and material costs became expensive and controls were becoming unnecessarily complicated and expensive. These reasons plus new technology forced the return to Single Line Reversing technology. Back in the 1800's three ``people transporting'' subways were built. A fourth system was built under the Pentagon in the 1950's or 1960's. It is difficult to find information on this one. All are Single Line Reversing systems. The difference between a Single Line Reversing and a Twin Line system is exactly as the names imply. The principle of the operation of these systems is covered herein. The physics for these two kinds of systems is the same. The Single Line Reversing system is technically more complex but capital and operating expense is far less costly. These costs are discussed herein.
TESTING ALTERNATIVE THEORIES OF GRAVITY USING THE SUN
Casanellas, Jordi; Pani, Paolo; Lopes, Ilidio; Cardoso, Vitor E-mail: paolo.pani@ist.utl.pt E-mail: vitor.cardoso@ist.utl.pt
2012-01-20
We propose a new approach to test possible corrections to Newtonian gravity using solar physics. The high accuracy of current solar models and new precise observations allow us to constrain corrections to standard gravity at unprecedented levels. Our case study is Eddington-inspired gravity, an attractive modified theory of gravity which results in non-singular cosmology and collapse. The theory is equivalent to standard gravity in vacuum, but it sensibly differs from it within matter. For instance, it affects the evolution and the equilibrium structure of the Sun, giving different core temperature profiles, and deviations in the observed acoustic modes and in solar neutrino fluxes. Comparing the predictions from a modified solar model with observations, we constrain the coupling parameter of the theory, |{kappa}{sub g}| {approx}< 3 Multiplication-Sign 10{sup 5} m{sup 5} s{sup -2} kg{sup -1}. Our results show that the Sun can be used to efficiently constrain alternative theories of gravity.
Finite field-dependent symmetries in perturbative quantum gravity
Upadhyay, Sudhaker
2014-01-15
In this paper we discuss the absolutely anticommuting nilpotent symmetries for perturbative quantum gravity in general curved spacetime in linear and non-linear gauges. Further, we analyze the finite field-dependent BRST (FFBRST) transformation for perturbative quantum gravity in general curved spacetime. The FFBRST transformation changes the gauge-fixing and ghost parts of the perturbative quantum gravity within functional integration. However, the operation of such symmetry transformation on the generating functional of perturbative quantum gravity does not affect the theory on physical ground. The FFBRST transformation with appropriate choices of finite BRST parameter connects non-linear Curci–Ferrari and Landau gauges of perturbative quantum gravity. The validity of the results is also established at quantum level using Batalin–Vilkovisky (BV) formulation. -- Highlights: •The perturbative quantum gravity is treated as gauge theory. •BRST and anti-BRST transformations are developed in linear and non-linear gauges. •BRST transformation is generalized by making it finite and field dependent. •Connection between linear and non-linear gauges is established. •Using BV formulation the results are established at quantum level also.
Plains and Eastern Clean Line Transmission Line: Comment from...
Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)
from Dr. Contreras Plains and Eastern Clean Line Transmission Line: Comment from Dr. Contreras Comment submitted on updated Part 2 application. PDF icon Comment from Dr. Contreras ...
Plains and Eastern Clean Line Transmission Line: Comment from...
Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)
Ms. Callahan Plains and Eastern Clean Line Transmission Line: Comment from Ms. Callahan Comment submitted on updated Part 2 application. PDF icon Comment from Ms. Callahan ...
Constraining modified gravity with large non-Gaussianities
Vazquez, Samuel E.
2009-02-15
In writing a covariant effective action for single-field inflation, one is allowed to add a Gauss-Bonnet and axion-type curvature couplings. These couplings represent modifications of gravity, and are the unique higher-curvature terms that lead to second order equations of motion in four dimensions. In this paper we study the observational consequences of such couplings for models with large non-Gaussianities. Our focus is on the Gauss-Bonnet term. In particular, we study an effective action where the scalar Lagrangian is a general function of the inflaton and its first derivative. We show that, for large non-Gaussianities, one can write f{sub NL} in terms of only three parameters. The shape of f{sub NL} is also studied, and we find that it is very similar to that of k-inflation. We show that the Gauss-Bonnet term enhances the production of gravitational waves, and allows a smaller speed of sound for scalar perturbations. This, in turn, can lead to larger non-Gaussianities which can be constrained by observations. Using current Wilkinson microwave anisotropy probe limits on f{sub NL} and the tensor/scalar ratio, we put constraints on all parameters. As an example, we show that for Dirac-Born-Infeld inflation, the Gauss-Bonnet coupling leads to an interesting observational window with both large f{sub NL} and a large amplitude of gravitational waves. Finally, we show that the Gauss-Bonnet coupling admits a de Sitter phase with a relativistic dispersion relation for scalar perturbations.
Not Available
1993-08-30
A stretch of Bonneville Power Administration transmission line between Spokane and the Grand Coulee Dam is an 82-mile bottleneck as it is the last 115-kv section of [open quotes]road[close quotes] along a 500-kv transmission [open quotes]highway[close quotes]. Soon the administration will change all that. A number of independent and utility powerplants have been proposed in Idaho, Montana and the Spokane, Wash., area during the 1990s. As the operators will need to move their power, Bonneville is planning to build a $144-million, 500-kv line to upgrade the 115-kv section. The agency is planning to use its existing right-of-way.
DeShong, J.A.
1960-03-01
A control-limiting device for monltoring a control system is described. The system comprises a conditionsensing device, a condition-varying device exerting a control over the condition, and a control means to actuate the condition-varying device. A control-limiting device integrates the total movement or other change of the condition-varying device over any interval of time during a continuum of overlapping periods of time, and if the tothl movement or change of the condition-varying device exceeds a preset value, the control- limiting device will switch the control of the operated apparatus from automatic to manual control.
McBranch, Duncan W.; Mattes, Benjamin R.; Koskelo, Aaron C.; Heeger, Alan J.; Robinson, Jeanne M.; Smilowitz, Laura B.; Klimov, Victor I.; Cha, Myoungsik; Sariciftci, N. Serdar; Hummelen, Jan C.
1998-01-01
Optical limiting materials. Methanofullerenes, fulleroids and/or other fullerenes chemically altered for enhanced solubility, in liquid solution, and in solid blends with transparent glass (SiO.sub.2) gels or polymers, or semiconducting (conjugated) polymers, are shown to be useful as optical limiters (optical surge protectors). The nonlinear absorption is tunable such that the energy transmitted through such blends saturates at high input energy per pulse over a wide range of wavelengths from 400-1100 nm by selecting the host material for its absorption wavelength and ability to transfer the absorbed energy into the optical limiting composition dissolved therein. This phenomenon should be generalizable to other compositions than substituted fullerenes.
ONE NEVADA LINE | Department of Energy
Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)
ONE NEVADA LINE ONE NEVADA LINE ONE NEVADA LINE ONE NEVADA LINE ONE NEVADA LINE ONE NEVADA LINE ONE NEVADA LINE ONE NEVADA LINE ONE NEVADA LINE ONE NEVADA LINE ONE NEVADA LINE ONE NEVADA LINE ONE NEVADA LINE ONE NEVADA LINE ONE NEVADA LINE PROJECT SUMMARY In February 2011, the Department of Energy issued a $343 million loan guarantee to finance the One Nevada Transmission Line (ON Line) project, a 235-mile, 500 kV AC transmission line capable of carrying 600 MW of power to the grid running
Nonlinear structure formation in nonlocal gravity
Barreira, Alexandre; Li, Baojiu; Hellwing, Wojciech A.; Baugh, Carlton M.; Pascoli, Silvia E-mail: baojiu.li@durham.ac.uk E-mail: c.m.baugh@durham.ac.uk
2014-09-01
We study the nonlinear growth of structure in nonlocal gravity models with the aid of N-body simulation and the spherical collapse and halo models. We focus on a model in which the inverse-squared of the d'Alembertian operator acts on the Ricci scalar in the action. For fixed cosmological parameters, this model differs from Î›CDM by having a lower late-time expansion rate and an enhanced and time-dependent gravitational strength âĽÂ 6% larger today). Compared to Î›CDM today, in the nonlocal model, massive haloes are slightly more abundant (by âĽÂ 10% at MÂ âĽÂ 10{sup 14}Â M{sub âŠ™}/h) and concentrated â‰Â 8% enhancement over a range of mass scales), but their linear bias remains almost unchanged. We find that the Sheth-Tormen formalism describes the mass function and halo bias very well, with little need for recalibration of free parameters. The fitting of the halo concentrations is however essential to ensure the good performance of the halo model on small scales. For kÂ âĽ>Â 1Â h/Mpc, the amplitude of the nonlinear matter and velocity divergence power spectra exhibits a modest enhancement of âĽÂ 12% to 15%, compared to Î›CDM today. This suggests that this model might only be distinguishable from Î›CDM by future observational missions. We point out that the absence of a screening mechanism may lead to tensions with Solar System tests due to local time variations of the gravitational strength, although this is subject to assumptions about the local time evolution of background averaged quantities.
Goldsworthy, W.W.; Robinson, J.B.
1959-03-31
A peak voltage amplitude limiting system adapted for use with a cascade type amplifier is described. In its detailed aspects, the invention includes an amplifier having at least a first triode tube and a second triode tube, the cathode of the second tube being connected to the anode of the first tube. A peak limiter triode tube has its control grid coupled to thc anode of the second tube and its anode connected to the cathode of the second tube. The operation of the limiter is controlled by a bias voltage source connected to the control grid of the limiter tube and the output of the system is taken from the anode of the second tube.
Gravity survey of the southwestern part of the sourthern Utah geothermal belt
Green, R.T.; Cook, K.L.
1981-03-01
A gravity survey covering an area of 6200 km/sup 2/ was made over the southwestern part of the southern Utah geothermal belt. The objective of the gravity survey is to delineate the geologic structures and assist in the understanding of the geothermal potential of the area. A total of 726 new gravity stations together with 205 existing gravity stations, are reduced to give: (1) a complete Bouguer gravity anomaly map, and (2) a fourth-order residual gravity anomaly map; both maps have a 2-mgal contour interval. The complete Bouguer gravity anomaly map shows an east-trending regional gravity belt with a total relief of about 70 mgal which crosses the central portion of the survey area. The gravity belt is attributed to a crustal lateral density variation of 0.1 gm/cc from a depth of 5 to 15 km.
PLAINS & EASTERN CLEAN LINE TRANSMISSION LINE | Department of Energy
Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)
Section 1222 of the Energy Policy Act 2005 Â» PLAINS & EASTERN CLEAN LINE TRANSMISSION LINE PLAINS & EASTERN CLEAN LINE TRANSMISSION LINE On March 25, 2016, U.S. Secretary of Energy Dr. Ernest Moniz announced that the Department of Energy (DOE) will participate in the development of the Plains & Eastern Clean Line project (Project), a major clean energy infrastructure project. Through section 1222 of the Energy Policy Act of 2005, Congress authorized DOE to promote electric
Correlation between precision gravity and subsidence measurements at Cerro Prieto
Zelwer, R.; Grannell, R.B.
1982-10-01
Precision gravity measurements were made in the region of the Cerro Prieto geothermal field at yearly intervals from 1977 to 1981 to assess the feasibility of using gravity to determine subsurface reservoir changes with time. The extent of mass recharge in response to the continued production of fluids from this field was studied. Changes in gravity and ground elevation were observed throughout the region for the period of observation. Results indicate that the largest changes observed were the result of the Magnitude 6.1 (Caltech) Victoria earthquake of 8 June 1980. The epicenter of this earthquake was located 25 km southeast of the field on the Cerro Prieto Fault, which bounds the field on the southwest. Subsidence of up to 55 cm was measured east of the power plant, in the region between the northern end of the Cerro Prieto Fault and the southern end of the Imperial Fault. This area has been postulated to be the site of an active spreading center or pull-apart basin, and has been characterized by a high level of seismic activity during the last 10 years. Minor subsidence and small related gravity changes for the period preceeding the Victoria earthquake suggest that in spite of large fluid production rates, the reservoir is being almost completely recharged and that a measurable increase in subsurface density may be taking place. The results of measurements of horizontal ground motions made in this area are discussed in relation to the gravity and subsidence observations.
Angular momentum transport via internal gravity waves in evolving stars
Fuller, Jim; Lecoanet, Daniel; Cantiello, Matteo; Brown, Ben
2014-11-20
Recent asteroseismic advances have allowed for direct measurements of the internal rotation rates of many subgiant and red giant stars. Unlike the nearly rigidly rotating Sun, these evolved stars contain radiative cores that spin faster than their overlying convective envelopes, but slower than they would in the absence of internal angular momentum transport. We investigate the role of internal gravity waves in angular momentum transport in evolving low-mass stars. In agreement with previous results, we find that convectively excited gravity waves can prevent the development of strong differential rotation in the radiative cores of Sun-like stars. As stars evolve into subgiants, however, low-frequency gravity waves become strongly attenuated and cannot propagate below the hydrogen-burning shell, allowing the spin of the core to decouple from the convective envelope. This decoupling occurs at the base of the subgiant branch when stars have surface temperatures of T â‰ 5500 K. However, gravity waves can still spin down the upper radiative region, implying that the observed differential rotation is likely confined to the deep core near the hydrogen-burning shell. The torque on the upper radiative region may also prevent the core from accreting high angular momentum material and slow the rate of core spin-up. The observed spin-down of cores on the red giant branch cannot be totally attributed to gravity waves, but the waves may enhance shear within the radiative region and thus increase the efficacy of viscous/magnetic torques.
First tsunami gravity wave detection in ionospheric radio occultation data
CoĂŻsson, Pierdavide; LognonnĂ©, Philippe; Walwer, Damian; Rolland, Lucie M.
2015-05-09
After the 11 March 2011 earthquake and tsunami off the coast of Tohoku, the ionospheric signature of the displacements induced in the overlying atmosphere has been observed by ground stations in various regions of the Pacific Ocean. We analyze here the data of radio occultation satellites, detecting the tsunami-driven gravity wave for the first time using a fully space-based ionospheric observation system. One satellite of the Constellation Observing System for Meteorology, Ionosphere and Climate (COSMIC) recorded an occultation in the region above the tsunami 2.5 h after the earthquake. The ionosphere was sounded from top to bottom, thus providing the vertical structure of the gravity wave excited by the tsunami propagation, observed as oscillations of the ionospheric Total Electron Content (TEC). The observed vertical wavelength was about 50 km, with maximum amplitude exceeding 1 total electron content unit when the occultation reached 200 km height. We compared the observations with synthetic data obtained by summation of the tsunami-coupled gravity normal modes of the Earth/Ocean/atmosphere system, which models the associated motion of the ionosphere plasma. These results provide experimental constraints on the attenuation of the gravity wave with altitude due to atmosphere viscosity, improving the understanding of the propagation of tsunami-driven gravity waves in the upper atmosphere. They demonstrate that the amplitude of the tsunami can be estimated to within 20% by the recorded ionospheric data.
First tsunami gravity wave detection in ionospheric radio occultation data
CoĂŻsson, Pierdavide; LognonnĂ©, Philippe; Walwer, Damian; Rolland, Lucie M.
2015-05-09
After the 11 March 2011 earthquake and tsunami off the coast of Tohoku, the ionospheric signature of the displacements induced in the overlying atmosphere has been observed by ground stations in various regions of the Pacific Ocean. We analyze here the data of radio occultation satellites, detecting the tsunami-driven gravity wave for the first time using a fully space-based ionospheric observation system. One satellite of the Constellation Observing System for Meteorology, Ionosphere and Climate (COSMIC) recorded an occultation in the region above the tsunami 2.5 h after the earthquake. The ionosphere was sounded from top to bottom, thus providing themoreÂ Â» vertical structure of the gravity wave excited by the tsunami propagation, observed as oscillations of the ionospheric Total Electron Content (TEC). The observed vertical wavelength was about 50 km, with maximum amplitude exceeding 1 total electron content unit when the occultation reached 200 km height. We compared the observations with synthetic data obtained by summation of the tsunami-coupled gravity normal modes of the Earth/Ocean/atmosphere system, which models the associated motion of the ionosphere plasma. These results provide experimental constraints on the attenuation of the gravity wave with altitude due to atmosphere viscosity, improving the understanding of the propagation of tsunami-driven gravity waves in the upper atmosphere. They demonstrate that the amplitude of the tsunami can be estimated to within 20% by the recorded ionospheric data.Â«Â less
Dynamic Line Rating: Research and Policy Evaluation
Jake P. Gentle; Kurt S. Myers; Michael R. West
2014-07-01
Dynamic Line Rating (DLR) is a smart grid technology that allows the rating of electrical conductors to be increased based on local weather conditions. Overhead lines are conventionally given a conservative rating based on worst case scenarios. We demonstrate that observing the conditions in real time leads to additional capacity and safer operation. This paper provides a report of a pioneering scheme in the United States of America in which DLR has been applied. Thereby, we demonstrate that observing the local weather conditions in real time leads to additional capacity and safer operation. Secondly, we discuss limitations involved. In doing so, we arrive at novel insights which will inform and improve future DLR projects. Third, we provide a policy background and discussion to clarify the technologyâ€™s potential and identifies barriers to the imminent adoption of dynamic line rating systems. We provide suggestions for regulatory bodies about possible improvements in policy to encourage adoption of this beneficial technology.
Printed circuit dispersive transmission line
Ikezi, H.; Lin-Liu, Y.R.; DeGrassie, J.S.
1991-08-27
A printed circuit dispersive transmission line structure is disclosed comprising an insulator, a ground plane formed on one surface of the insulator, a first transmission line formed on a second surface of the insulator, and a second transmission line also formed on the second surface of the insulator and of longer length than the first transmission line and periodically intersecting the first transmission line. In a preferred embodiment, the transmission line structure exhibits highly dispersive characteristics by designing the length of one of the transmission line between two adjacent periodic intersections to be longer than the other. 5 figures.
Printed circuit dispersive transmission line
Ikezi, Hiroyuki; Lin-Liu, Yuh-Ren; DeGrassie, John S.
1991-01-01
A printed circuit dispersive transmission line structure is disclosed comprising an insulator, a ground plane formed on one surface of the insulator, a first transmission line formed on a second surface of the insulator, and a second transmission line also formed on the second surface of the insulator and of longer length than the first transmission line and periodically intersecting the first transmission line. In a preferred embodiment, the transmission line structure exhibits highly dispersive characteristics by designing the length of one of the transmission line between two adjacent periodic intersections to be longer than the other.
Quantum optics. Gravity meets quantum physics
Adams, Bernhard W.
2015-02-27
Albert Einsteinâ€™s general theory of relativity is a classical formulation but a quantum mechanical description of gravitational forces is needed, not only to investigate the coupling of classical and quantum systems but simply to give a more complete description of our physical surroundings. In this issue of Nature Photonics, Wen-Te Liao and Sven Ahrens reveal a link between quantum and gravitational physics. They propose that in the quantum-optical effect of superradiance, the world line of electromagnetic radiation is changed by the presence of a gravitational field.
Keeton, Charles R.; Petters, A.O.
2005-11-15
We are developing a general, unified, and rigorous analytical framework for using gravitational lensing by compact objects to test different theories of gravity beyond the weak-deflection limit. In this paper we present the formalism for computing corrections to lensing observables for static, spherically symmetric gravity theories in which the corrections to the weak-deflection limit can be expanded as a Taylor series in one parameter, namely, the gravitational radius of the lens object. We take care to derive coordinate-independent expressions and compute quantities that are directly observable. We compute series expansions for the observables that are accurate to second order in the ratio {epsilon}={theta} /{theta}{sub E} of the angle subtended by the lens's gravitational radius to the weak-deflection Einstein radius, which scales with mass as {epsilon}{proportional_to}M {sup 1/2}. The positions, magnifications, and time delays of the individual images have corrections at both first and second order in {epsilon}, as does the differential time delay between the two images. Interestingly, we find that the first-order corrections to the total magnification and centroid position vanish in all gravity theories that agree with general relativity in the weak-deflection limit, but they can remain nonzero in modified theories that disagree with general relativity in the weak-deflection limit. For the Reissner-Nordstroem metric and a related metric from heterotic string theory, our formalism reveals an intriguing connection between lensing observables and the condition for having a naked singularity, which could provide an observational method for testing the existence of such objects. We apply our formalism to the galactic black hole and predict that the corrections to the image positions are at the level of 10 {mu}arc s (microarcseconds), while the correction to the time delay is a few hundredths of a second. These corrections would be measurable today if a pulsar were
Peralta, J.; LĂłpez-Valverde, M. A.; Imamura, T.; Read, P. L.; Luz, D.; Piccialli, A.
2014-07-01
This paper is the first of a two-part study devoted to developing tools for a systematic classification of the wide variety of atmospheric waves expected on slowly rotating planets with atmospheric superrotation. Starting with the primitive equations for a cyclostrophic regime, we have deduced the analytical solution for the possible waves, simultaneously including the effect of the metric terms for the centrifugal force and the meridional shear of the background wind. In those cases when the conditions for the method of the multiple scales in height are met, these wave solutions are also valid when vertical shear of the background wind is present. A total of six types of waves have been found and their properties were characterized in terms of the corresponding dispersion relations and wave structures. In this first part, only waves that are direct solutions of the generic dispersion relation are studiedâ€”acoustic and inertia-gravity waves. Concerning inertia-gravity waves, we found that in the cases of short horizontal wavelengths, null background wind, or propagation in the equatorial region, only pure gravity waves are possible, while for the limit of large horizontal wavelengths and/or null static stability, the waves are inertial. The correspondence between classical atmospheric approximations and wave filtering has been examined too, and we carried out a classification of the mesoscale waves found in the clouds of Venus at different vertical levels of its atmosphere. Finally, the classification of waves in exoplanets is discussed and we provide a list of possible candidates with cyclostrophic regimes.
Improved limited discrepancy search
Korf, R.E.
1996-12-31
We present an improvement to Harvey and Ginsberg`s limited discrepancy search algorithm, which eliminates much of the redundancy in the original, by generating each path from the root to the maximum search depth only once. For a complete binary tree of depth d this reduces the asymptotic complexity from O(d+2/2 2{sup d}) to O(2{sup d}). The savings is much less in a partial tree search, or in a heavily pruned tree. The overhead of the improved algorithm on a complete binary tree is only a factor of b/(b - 1) compared to depth-first search. While this constant factor is greater on a heavily pruned tree, this improvement makes limited discrepancy search a viable alternative to depth-first search, whenever the entire tree may not be searched. Finally, we present both positive and negative empirical results on the utility of limited discrepancy search, for the problem of number partitioning.
Drill string transmission line
Hall, David R.; Hall, Jr., H. Tracy; Pixton, David S.; Bradford, Kline; Fox, Joe
2006-03-28
A transmission line assembly for transmitting information along a downhole tool comprising a pin end, a box end, and a central bore traveling between the pin end and the box end, is disclosed in one embodiment of the invention as including a protective conduit. A transmission line is routed through the protective conduit. The protective conduit is routed through the central bore and the ends of the protective conduit are routed through channels formed in the pin end and box end of the downhole tool. The protective conduit is elastically forced into a spiral or other non-linear path along the interior surface of the central bore by compressing the protective conduit to a length within the downhole tool shorter than the protective conduit.
Bone, W.H.; Schmidt, W.W.
1958-11-01
A method is presented for forming refractory liners in cylindrical reaction vessels used for the reductlon of uranium tetrafluoride to metallic uranium. A preliminary form, having positioning lugs attached thereto, is inserted into the reaction vessel and the refractory powder, usually CaO, is put in the annular space between the form and the inner wall of the reaction vessel. A jolting table is used to compact this charge of liner material ln place, and after thls has been done, the preliminary form is removed and the flnal form or plug is lnserted without disturbing the partially completed lining. The remainder of the lining charge is then introduced and compacted by jolting, after which the form is removed.
McBranch, D.W.; Mattes, B.R.; Koskelo, A.C.; Heeger, A.J.; Robinson, J.M.; Smilowitz, L.B.; Klimov, V.I.; Cha, M.; Sariciftci, N.S.; Hummelen, J.C.
1998-04-21
Methanofullerenes, fulleroids and/or other fullerenes chemically altered for enhanced solubility, in liquid solution, and in solid blends with transparent glass (SiO{sub 2}) gels or polymers, or semiconducting (conjugated) polymers, are shown to be useful as optical limiters (optical surge protectors). The nonlinear absorption is tunable such that the energy transmitted through such blends saturates at high input energy per pulse over a wide range of wavelengths from 400--1,100 nm by selecting the host material for its absorption wavelength and ability to transfer the absorbed energy into the optical limiting composition dissolved therein. This phenomenon should be generalizable to other compositions than substituted fullerenes. 5 figs.
Security Clearances; Limitations
Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)
SEC. 1072. SECURITY CLEARANCES; LIMITATIONS. (a) In General.-Title III of the Intelligence Reform and Terrorism Prevention Act of 2004 (50 U.S.C. 435b) is amended by adding at the end the following new section: "SEC. 3002. SECURITY CLEARANCES; LIMITATIONS. "(a) Definitions.-In this section: "(1) Controlled substance.-The term `controlled substance' has the meaning given that term in section 102 of the Controlled Substances Act (21 U.S.C. 802). "(2) Covered person.-The term
On the null trajectories in conformal Weyl gravity
Villanueva, J.R.; Olivares, Marco E-mail: marco.olivaresrubilar@gmail.com
2013-06-01
In this work we find analytical solutions to the null geodesics around a black hole in the conformal Weyl gravity. Exact expressions for the horizons are found, and they depend on the cosmological constant and the coupling constants of the conformal Weyl gravity. Then, we study the radial motion from the point of view of the proper and coordinate frames, and compare it with that found in spacetimes of general relativity. The angular motion is also examined qualitatively by means of an effective potential; quantitatively, the equation of motion is solved in terms of wp-Weierstrass elliptic function. Thus, we find the deflection angle for photons without using any approximation, which is a novel result for this kind of gravity.
Monitoring the Bulalo geothermal reservoir, Philippines, using precision gravity data
San Andres, R.B.; Pedersen, J.R.
1993-10-01
Precision gravity monitoring of the Bulalo geothermal field began in 1980 to estimate the natural mass recharge to the reservoir. Between 1980 and 1991, gravity decreases exceeding 2.5 {times} 10{sup {minus}6} N/kg (250 microgals) were observed in response to fluid withdrawals. A maximum rate of {minus}26 microgals per year was observed near the production center. Mass discharges predicted by recent reservoir simulation modeling generally match those inferred from the observed gravity data. According to simulation studies, no recharge occurred between 1980 and 1984. The mass recharge between 1984 and 1991 was estimated to be 30% of net fluid withdrawal during the same period, equivalent to an average rate of 175 kg/s (630 metric tons per hour).
Yield Line Evaluation Methodology for Reinforced Concrete Structures
Energy Science and Technology Software Center
1998-12-30
Yield line theory is an analytical technique that can be used to determine the ultimate bending capacity of flat reinforced concrete plates subject to distributed and concentrated loadings. Alternately, yield line theory, combined with rotation limits can be used to determine the energy absorption capacity of plates subject to impulsive and impact loadings. Typical components analyzed by yield line theory are basemats, floor and roof slabs subject to vertical loads along with walls subject tomoreÂ Â» out of plane loadings. One limitation of yield line theory is that it is computationally difficult to evaluate some mechanisms. This problem is aggravated by the complex geometry and reinforcing layouts commonly found in practice. The program has the capability to either evaluate a single user defined mechanism or to iterate over a range of mechanisms to determine the minimum ultimate capacity. The program is verified by comparison to a series of yield line mechanisms with known solutions.Â«Â less
On axionic field ranges, loopholes and the weak gravity conjecture
Brown, Jon; Cottrell, William; Shiu, Gary; Soler, Pablo
2016-04-05
Here, we clarify some aspects of the impact that the Weak Gravity Conjecture has on models of (generalized) natural inflation. In particular we address certain technical and conceptual concerns recently raised regarding the stringent constraints and conclusions found in our previous work. We also point out the difficulties faced by attempts to evade these constraints. Furthermore, these new considerations improve the understanding of the quantum gravity constraints we found and further support the conclusion that it remains challenging for axions to drive natural inflation.
Spectral regularisation: induced gravity and the onset of inflation
Kurkov, Max A.; Sakellariadou, Mairi E-mail: mairi.sakellariadou@kcl.ac.uk
2014-01-01
Using spectral regularisation, we compute the Weyl anomaly and express the anomaly generating functional of the quantum effective action through a collective scalar degree of freedom of all quantum vacuum fluctuations. Such a formulation allows us to describe induced gravity on an equal footing with the anomaly-induced effective action, in a self-consistent way. We then show that requiring stability of the cosmological constant under loop quantum corrections, Sakharov's induced gravity and Starobinsky's anomaly-induced inflation are either both present or both absent, depending on the particle content of the theory.
Minimum length, extra dimensions, modified gravity and black hole remnants
Maziashvili, Michael
2013-03-01
We construct a Hilbert space representation of minimum-length deformed uncertainty relation in presence of extra dimensions. Following this construction, we study corrections to the gravitational potential (back reaction on gravity) with the use of correspondingly modified propagator in presence of two (spatial) extra dimensions. Interestingly enough, for r?0 the gravitational force approaches zero and the horizon for modified Schwarzschild-Tangherlini space-time disappears when the mass approaches quantum-gravity energy scale. This result points out to the existence of zero-temperature black hole remnants in ADD brane-world model.
Stabilization of linear higher derivative gravity with constraints
Chen, Tai-jun; Lim, Eugene A. E-mail: eugene.a.lim@gmail.com
2014-05-01
We show that the instabilities of higher derivative gravity models with quadratic curvature invariant ?R{sup 2}+?R{sub ??}R{sup ??} can be removed by judicious addition of constraints at the quadratic level of metric fluctuations around Minkowski/de Sitter background. With a suitable parameter choice, we find that the instabilities of helicity-0, 1, 2 modes can be removed while reducing the dimensionality of the original phase space. To retain the renormalization properties of higher derivative gravity, Lorentz symmetry in the constrained theory is explicitly broken.
Gravity Survey of the Carson Sink - Data and Maps
Faulds, James E.
Preliminary Interpretation of Results: The Carson Sink is a complex composite basin with several major depocenters (Figures 15 and 16). Major depocenters are present in the south?central, east?central, and northeastern parts of the basin. The distribution of gravity anomalies suggests a complex pattern of faulting in the subsurface of the basin, with many fault terminations, step?overs, and accommodation zones. The pattern of faulting implies that other, previously undiscovered blind geothermal systems are likely in the Carson Sink. The gravity survey was completed near the end of this project. Thus, more thorough analysis of the data and potential locations of blind geothermal systems is planned for future work.
Flat 3-brane with Tension in Cascading Gravity
Rham, Claudia de; Khoury, Justin; Tolley, Andrew
2009-10-16
In the cascading gravity brane-world scenario, our 3-brane lies within a succession of lower-codimension branes, each with their own induced gravity term, embedded into each other in a higher-dimensional space-time. In the (6+1)-dimensional version of this scenario, we show that a 3-brane with tension remains flat, at least for sufficiently small tension that the weak-field approximation is valid. The bulk solution is singular nowhere and remains in the perturbative regime everywhere.
Gravitomagnetic gyroscope precession in Palatini f(R) gravity
Ruggiero, Matteo Luca
2009-04-15
We study gravitomagnetic effects in the Palatini formalism of f(R) gravity. On using the Kerr-de Sitter metric, which is a solution of f(R) field equations, we calculate the impact of f(R) gravity on the gravitomagnetic precession of an orbiting gyroscope. We show that, even though an f(R) contribution is present in principle, its magnitude is negligibly small and far to be detectable in the present (like GP-B) and foreseeable space missions or observational tests around the Earth.
Gravity Survey of the Carson Sink - Data and Maps
Faulds, James E.
2013-12-31
Preliminary Interpretation of Results: The Carson Sink is a complex composite basin with several major depocenters (Figures 15 and 16). Major depocenters are present in the south?central, east?central, and northeastern parts of the basin. The distribution of gravity anomalies suggests a complex pattern of faulting in the subsurface of the basin, with many fault terminations, step?overs, and accommodation zones. The pattern of faulting implies that other, previously undiscovered blind geothermal systems are likely in the Carson Sink. The gravity survey was completed near the end of this project. Thus, more thorough analysis of the data and potential locations of blind geothermal systems is planned for future work.
Spherically symmetric static spacetimes in vacuum f(T) gravity
Ferraro, Rafael; Fiorini, Franco
2011-10-15
We show that Schwarzschild geometry remains as a vacuum solution for those four-dimensional f(T) gravitational theories behaving as ultraviolet deformations of general relativity. In the gentler context of three-dimensional gravity, we also find that the infrared-deformed f(T) gravities, like the ones used to describe the late cosmic speed up of the Universe, have as the circularly symmetric vacuum solution a Deser-de Sitter or a Banados, Teitelboim and Zanelli-like spacetime with an effective cosmological constant depending on the infrared scale present in the function f(T).
High frequency background quantization of gravity
von Borzeszkowski, H.
1982-06-01
Considering background quantization of gravitational fields, it is generally assumed that the classical background satisfies Einstein's gravitational equations. However, there exist arguments showing that, for high frequency (quantum) fluctuations, this assumption has to be replaced by a condition describing the back reaction of fluctuations on the background. It is shown that such an approach leads to limitations for the quantum procedure which occur at distances larger than Planck's elementary length 1 = (Gh/c/sup 3/)/sup 1/2/.
Constraining models of f(R) gravity with Planck and WiggleZ power spectrum data
Dossett, Jason; Parkinson, David; Hu, Bin E-mail: hu@lorentz.leidenuniv.nl
2014-03-01
In order to explain cosmic acceleration without invoking ''dark'' physics, we consider f(R) modified gravity models, which replace the standard Einstein-Hilbert action in General Relativity with a higher derivative theory. We use data from the WiggleZ Dark Energy survey to probe the formation of structure on large scales which can place tight constraints on these models. We combine the large-scale structure data with measurements of the cosmic microwave background from the Planck surveyor. After parameterizing the modification of the action using the Compton wavelength parameter B{sub 0}, we constrain this parameter using ISiTGR, assuming an initial non-informative log prior probability distribution of this cross-over scale. We find that the addition of the WiggleZ power spectrum provides the tightest constraints to date on B{sub 0} by an order of magnitude, giving log{sub 10}(B{sub 0}) < ?4.07 at 95% confidence limit. Finally, we test whether the effect of adding the lensing amplitude A{sub Lens} and the sum of the neutrino mass ?m{sub ?} is able to reconcile current tensions present in these parameters, but find f(R) gravity an inadequate explanation.
PLAINS & EASTERN CLEAN LINE TRANSMISSION LINE | Department of...
U.S. Department of Energy (DOE) - all webpages (Extended Search)
PLAINS & EASTERN CLEAN LINE TRANSMISSION LINE On March 25, 2016, U.S. Secretary of Energy Dr. Ernest Moniz announced that the Department of Energy (DOE) will participate in the ...
On the gauge features of gravity on a Lie algebroid structure
Fabi, S. Harms, B. Hou, S.
2014-03-15
We present the geometric formulation of gravity based on the mathematical structure of a Lie Algebroid. We show that this framework provides the geometrical setting to describe the gauge propriety of gravity.
Problems with propagation and time evolution inf(T)gravity (Journal...
Office of Scientific and Technical Information (OSTI)
Problems with propagation and time evolution inf(T)gravity Citation Details In-Document Search Title: Problems with propagation and time evolution inf(T)gravity Authors: Ong, Yen...
Toward large N thermal QCD from dual gravity: The heavy quarkonium...
Office of Scientific and Technical Information (OSTI)
Toward large N thermal QCD from dual gravity: The heavy quarkonium potential Citation Details In-Document Search Title: Toward large N thermal QCD from dual gravity: The heavy ...
How Does Gravity Work to Hold a Human Down? | GE Global Research
U.S. Department of Energy (DOE) - all webpages (Extended Search)
Does Gravity Work to Hold a Human Down? Click to email this to a friend (Opens in new ... How Does Gravity Work to Hold a Human Down? 2012.04.13 Chief Scientist Jim Bray discusses ...
Harris, William G. (Tampa, FL)
1985-01-01
A heat limiting tubular sleeve extending over only a portion of a tube having a generally uniform outside diameter, the sleeve being open on both ends, having one end thereof larger in diameter than the other end thereof and having a wall thickness which decreases in the same direction as the diameter of the sleeve decreases so that the heat transfer through the sleeve and tube is less adjacent the large diameter end of the sleeve than adjacent the other end thereof.
Complete Bouguer gravity map of the Nevada Test Site and vicinity, Nevada
Healey, D.L.; Harris, R.N.; Ponce, D.A.; Oliver, H.W.
1987-12-31
About 15,000 gravity stations were used to create the gravity map. Gravity studies at the Nevada Test Site were undertaken to help locate geologically favorable areas for underground nuclear tests and to help characterize potential high-level nuclear waste storage sites. 48 refs. (TEM)
Extreme neutron stars from Extended Theories of Gravity
Astashenok, Artyom V.; Capozziello, Salvatore; Odintsov, Sergei D. E-mail: capozziello@na.infn.it
2015-01-01
We discuss neutron stars with strong magnetic mean fields in the framework of Extended Theories of Gravity. In particular, we take into account models derived from f(R) and f(G) extensions of General Relativity where functions of the Ricci curvature invariant R and the Gauss-Bonnet invariant G are respectively considered. Dense matter in magnetic mean field, generated by magnetic properties of particles, is described by assuming a model with three meson fields and baryons octet. As result, the considerable increasing of maximal mass of neutron stars can be achieved by cubic corrections in f(R) gravity. In principle, massive stars with M > 4M{sub ?} can be obtained. On the other hand, stable stars with high strangeness fraction (with central densities ?{sub c} ? 1.5–2.0 GeV/fm{sup 3}) are possible considering quadratic corrections of f(G) gravity. The magnetic field strength in the star center is of order 6–8 × 10{sup 18} G. In general, we can say that other branches of massive neutron stars are possible considering the extra pressure contributions coming from gravity extensions. Such a feature can constitute both a probe for alternative theories and a way out to address anomalous self-gravitating compact systems.
On singularities of capillary surfaces in the absence of gravity
Roytburd, V.
1983-01-01
We study numerical solutions to the equation of capillary surfaces in trapezoidal domains in the absence of gravity when the boundary contact angle declines from 90 ° to some critical value. We also discuss a result on the behavior of solutions in more general domains that confirms numerical calculations.
Entirely passive heat pipe apparatus capable of operating against gravity
Koenig, Daniel R.
1982-01-01
The disclosure is directed to an entirely passive heat pipe apparatus capable of operating against gravity for vertical distances in the order of 3 to 7 meters and more. A return conduit into which an inert gas is introduced is used to lower the specific density of the working fluid so that it may be returned a greater vertical distance from condenser to evaporator.
Cartan gravity, matter fields, and the gauge principle
Westman, Hans F.; Zlosnik, Tom G.
2013-07-15
Gravity is commonly thought of as one of the four force fields in nature. However, in standard formulations its mathematical structure is rather different from the Yang–Mills fields of particle physics that govern the electromagnetic, weak, and strong interactions. This paper explores this dissonance with particular focus on how gravity couples to matter from the perspective of the Cartan-geometric formulation of gravity. There the gravitational field is represented by a pair of variables: (1) a ‘contact vector’ V{sup A} which is geometrically visualized as the contact point between the spacetime manifold and a model spacetime being ‘rolled’ on top of it, and (2) a gauge connection A{sub ?}{sup AB}, here taken to be valued in the Lie algebra of SO(2,3) or SO(1,4), which mathematically determines how much the model spacetime is rotated when rolled. By insisting on two principles, the gauge principle and polynomial simplicity, we shall show how one can reformulate matter field actions in a way that is harmonious with Cartan’s geometric construction. This yields a formulation of all matter fields in terms of first order partial differential equations. We show in detail how the standard second order formulation can be recovered. In particular, the Hodge dual, which characterizes the structure of bosonic field equations, pops up automatically. Furthermore, the energy–momentum and spin-density three-forms are naturally combined into a single object here denoted the spin-energy–momentum three-form. Finally, we highlight a peculiarity in the mathematical structure of our first-order formulation of Yang–Mills fields. This suggests a way to unify a U(1) gauge field with gravity into a SO(1,5)-valued gauge field using a natural generalization of Cartan geometry in which the larger symmetry group is spontaneously broken down to SO(1,3)×U(1). The coupling of this unified theory to matter fields and possible extensions to non-Abelian gauge fields are left as open questions
Multi-gravity separator: an alternate gravity concentrator to process coal fines
Majumder, A.K.; Bhoi, K.S.; Barnwal, J.P.
2007-08-15
The multi-gravity separator (MGS) is a novel piece of equipment for the separation of fine and ultra-fine minerals. However, the published literature does not demonstrate its use in the separation of coal fines. Therefore, an attempt was made to study the effects of different process variables on the performance of an MGS for the beneficiation of coal fines. The results obtained from this study revealed that among the parameters studied, drum rotation and feed solids concentration play dominating roles in controlling the yield and ash content of the clean coal. Mathematical modeling equations that correlate the variables studied and the yield and ash contents of the clean coal were developed to predict the performance of an MGS under different operating and design conditions. The entire exercise revealed that the MGS could produce a clean coal with an ash content of 14.67% and a yield of 71.23% from a feed coal having an ash content of 24.61 %.
Darmann, Francis Anthony
2013-10-08
A fault current limiter (FCL) includes a series of high permeability posts for collectively define a core for the FCL. A DC coil, for the purposes of saturating a portion of the high permeability posts, surrounds the complete structure outside of an enclosure in the form of a vessel. The vessel contains a dielectric insulation medium. AC coils, for transporting AC current, are wound on insulating formers and electrically interconnected to each other in a manner such that the senses of the magnetic field produced by each AC coil in the corresponding high permeability core are opposing. There are insulation barriers between phases to improve dielectric withstand properties of the dielectric medium.
(Limiting the greenhouse effect)
Rayner, S.
1991-01-07
Traveler attended the Dahlem Research Conference organized by the Freien Universitat, Berlin. The subject of the conference was Limiting the Greenhouse Effect: Options for Controlling Atmospheric CO{sub 2} Accumulation. Like all Dahlem workshops, this was a meeting of scientific experts, although the disciplines represented were broader than usual, ranging across anthropology, economics, international relations, forestry, engineering, and atmospheric chemistry. Participation by scientists from developing countries was limited. The conference was divided into four multidisciplinary working groups. Traveler acted as moderator for Group 3 which examined the question What knowledge is required to tackle the principal social and institutional barriers to reducing CO{sub 2} emissions'' The working rapporteur was Jesse Ausubel of Rockefeller University. Other working groups examined the economic costs, benefits, and technical feasibility of options to reduce emissions per unit of energy service; the options for reducing energy use per unit of GNP; and the significant of linkage between strategies to reduce CO{sub 2} emissions and other goals. Draft reports of the working groups are appended. Overall, the conference identified a number of important research needs in all four areas. It may prove particularly important in bringing the social and institutional research needs relevant to climate change closer to the forefront of the scientific and policy communities than hitherto.
Prepermit work starts on California crude line
Not Available
1991-04-08
This paper reports on preliminary work leading to permitting efforts for a 171 mile pipeline to move low gravity crude from giant fields of California to the Los Angeles area. The 20 in., unheated pipeline would cost $180-190 million and could go on stream in 3-3 1/2 years. The project has the backing of partners in development of giant Point Arguello field in the Santa Maria basin off Santa Barbara County, a project blocked from start-up for more than 3 years by permitting wrangles. Pipeline sponsors also have proposed moving oil production from development of Santa Ynez Unit in the Santa Barbara Channel. Point Arguello production is expected to start this year with flow limited to 20,000 b/d, moving moved by pipeline to refineries outside Los Angeles. Point Arguello partners want to ship full Arguello production of 80,000-100,00 b/d by tanker until the PPC project is complete, which the county opposes. The group has appealed the county's denial of an interim tankering permit to the California Coastal Commission, which is expected to hold a hearing on the matter this month. The controversy has been further complicated by other, competing projects designed to move Point Arguello crude to market.
Timminco Limited | Open Energy Information
OpenEI (Open Energy Information) [EERE & EIA]
Limited Jump to: navigation, search Name: Timminco Limited Place: Toronto, Ontario, Canada Zip: M5H 1J9 Product: Canadian manufacturer of magnesium and silicon; operates its...
Plains and Eastern Clean Line Transmission Line: Federal Register Notice,
Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)
Volume 80, No. 81 - April 28, 2015 | Department of Energy Federal Register Notice, Volume 80, No. 81 - April 28, 2015 Plains and Eastern Clean Line Transmission Line: Federal Register Notice, Volume 80, No. 81 - April 28, 2015 The Department of Energy (DOE) requests public comment on the first complete application submitted in response to its June 10, 2010 Request for Proposals for New or Upgraded Transmission Line Projects Under Section 1222 of the Energy Policy Act of 2005 in the Federal
Rhodes, Mark A.
2008-10-21
A bipolar pulse forming transmission line module for linear induction accelerators having first, second, third, fourth, and fifth planar conductors which form an interleaved stack with dielectric layers between the conductors. Each conductor has a first end, and a second end adjacent an acceleration axis. The first and second planar conductors are connected to each other at the second ends, the fourth and fifth planar conductors are connected to each other at the second ends, and the first and fifth planar conductors are connected to each other at the first ends via a shorting plate adjacent the first ends. The third planar conductor is electrically connectable to a high voltage source, and an internal switch functions to short a high voltage from the first end of the third planar conductor to the first end of the fourth planar conductor to produce a bipolar pulse at the acceleration axis with a zero net time integral. Improved access to the switch is enabled by an aperture through the shorting plate and the proximity of the aperture to the switch.
EC Transmission Line Materials
Bigelow, Tim S
2012-05-01
The purpose of this document is to identify materials acceptable for use in the US ITER Project Office (USIPO)-supplied components for the ITER Electron cyclotron Heating and Current Drive (ECH&CD) transmission lines (TL), PBS-52. The source of material property information for design analysis shall be either the applicable structural code or the ITER Material Properties Handbook. In the case of conflict, the ITER Material Properties Handbook shall take precedence. Materials selection, and use, shall follow the guidelines established in the Materials Assessment Report (MAR). Materials exposed to vacuum shall conform to the ITER Vacuum Handbook. [Ref. 2] Commercial materials shall conform to the applicable standard (e.g., ASTM, JIS, DIN) for the definition of their grade, physical, chemical and electrical properties and related testing. All materials for which a suitable certification from the supplier is not available shall be tested to determine the relevant properties, as part of the procurement. A complete traceability of all the materials including welding materials shall be provided. Halogenated materials (example: insulating materials) shall be forbidden in areas served by the detritiation systems. Exceptions must be approved by the Tritium System and Safety Section Responsible Officers.
Cosmological perturbations in non-local higher-derivative gravity
Craps, Ben; Jonckheere, Tim De; Koshelev, Alexey S. E-mail: Tim.De.Jonckheere@vub.ac.be
2014-11-01
We study cosmological perturbations in a non-local higher-derivative model of gravity introduced by Biswas, Mazumdar and Siegel. We extend previous work, which had focused on classical scalar perturbations around a cosine hyperbolic bounce solution, in three ways. First, we point out the existence of a Starobinsky solution in this model, which is more attractive from a phenomenological point of view (even though it has no bounce). Second, we study classical vector and tensor pertuxsxrbations. Third, we show how to quantize scalar and tensor perturbations in a de Sitter phase (for choices of parameters such that the model is ghost-free). Our results show that the model is well-behaved at this level, and are very similar to corresponding results in local f(R) models. In particular, for the Starobinsky solution of non-local higher-derivative gravity, we find the same tensor-to-scalar ratio as for the conventional Starobinsky model.
Translation invariant time-dependent solutions to massive gravity
Mourad, J.; Steer, D.A. E-mail: steer@apc.univ-paris7.fr
2013-12-01
Homogeneous time-dependent solutions of massive gravity generalise the plane wave solutions of the linearised Fierz-Pauli equations for a massive spin-two particle, as well as the Kasner solutions of General Relativity. We show that they also allow a clear counting of the degrees of freedom and represent a simplified framework to work out the constraints, the equations of motion and the initial value formulation. We work in the vielbein formulation of massive gravity, find the phase space resulting from the constraints and show that several disconnected sectors of solutions exist some of which are unstable. The initial values determine the sector to which a solution belongs. Classically, the theory is not pathological but quantum mechanically the theory may suffer from instabilities. The latter are not due to an extra ghost-like degree of freedom.
Trapping and aerogelation of nanoparticles in negative gravity hydrocarbon flames
Chakrabarty, Rajan K.; Novosselov, Igor V.; Beres, Nicholas D.; Moosmüller, Hans; Sorensen, Christopher M.; Stipe, Christopher B.
2014-06-16
We report the experimental realization of continuous carbon aerogel production using a flame aerosol reactor by operating it in negative gravity (?g; up-side-down configuration). Buoyancy opposes the fuel and air flow forces in ?g, which eliminates convectional outflow of nanoparticles from the flame and traps them in a distinctive non-tipping, flicker-free, cylindrical flame body, where they grow to millimeter-size aerogel particles and gravitationally fall out. Computational fluid dynamics simulations show that a closed-loop recirculation zone is set up in ?g flames, which reduces the time to gel for nanoparticles by ?10{sup 6}?s, compared to positive gravity (upward rising) flames. Our results open up new possibilities of one-step gas-phase synthesis of a wide variety of aerogels on an industrial scale.
Domestic Crude Oil First Purchase Prices by API Gravity
Energy Information Administration (EIA) (indexed site)
API Gravity (Dollars per Barrel) Period: Monthly Annual Download Series History Download Series History Definitions, Sources & Notes Definitions, Sources & Notes API Gravity Mar-16 Apr-16 May-16 Jun-16 Jul-16 Aug-16 View History 20.0Âş or Less 31.93 34.72 40.00 40.44 37.34 39.18 1993-2016 20.1Âş to 25.0Âş 33.32 35.99 41.97 43.04 39.42 40.45 1993-2016 25.1Âş to 30.0Âş 27.70 31.68 37.41 37.93 33.47 34.17 1993-2016 30.1Âş to 35.0Âş 31.90 35.92 40.94 44.51 41.82 41.22 1993-2016 35.1Âş to
Percentages of Total Imported Crude Oil by API Gravity
Energy Information Administration (EIA) (indexed site)
Percentages of Total Imported Crude Oil by API Gravity (Percent by Interval) Period: Monthly Annual Download Series History Download Series History Definitions, Sources & Notes Definitions, Sources & Notes API Gravity Mar-16 Apr-16 May-16 Jun-16 Jul-16 Aug-16 View History 20.0Âş or Less 15.82 15.37 15.79 16.03 16.65 19.61 1983-2016 20.1Âş to 25.0Âş 40.58 40.60 44.06 37.92 40.00 38.13 1983-2016 25.1Âş to 30.0Âş 6.44 5.96 8.63 10.60 10.98 8.27 1983-2016 30.1Âş to 35.0Âş 28.91 26.65 21.40
Galileon gravity and its relevance to late time cosmic acceleration
Gannouji, Radouane; Sami, M.
2010-07-15
We consider the covariant Galileon gravity taking into account the third order and fourth order scalar field Lagrangians L{sub 3}({pi}) and L{sub 4}({pi}), consisting of three and four {pi}'s with four and five derivatives acting on them, respectively. The background dynamical equations are set up for the system under consideration and the stability of the self-accelerating solution is demonstrated in a general setting. We extended this study to the general case of the fifth order theory. For the spherically symmetric static background, we spell out conditions for the suppression of fifth force effects mediated by the Galileon field {pi}. We study field perturbations in the fixed background and investigate the conditions for their causal propagation. We also briefly discuss metric fluctuations and derive an evolution equation for matter perturbations in Galileon gravity.
Crude Oil and Lease Condensate Production by API Gravity
Gasoline and Diesel Fuel Update
Lease Condensate Production by API Gravity Period-Unit: Monthly-Thousand Barrels per Day Download Series History Download Series History Definitions, Sources & Notes Definitions, Sources & Notes API Gravity Mar-16 Apr-16 May-16 Jun-16 Jul-16 Aug-16 View History Lower 48 States 8,663 8,458 8,377 8,241 8,255 8,285 2015-2016 20.0Âş or Lower 408 405 407 398 406 397 2015-2016 20.1Âş to 25.0Âş 178 168 167 172 175 170 2015-2016 25.1Âş to 30.0Âş 733 714 692 667 759 714 2015-2016 30.1Âş to 35.0Âş
Constraints on axion inflation from the weak gravity conjecture
Rudelius, Tom
2015-09-08
We derive constraints facing models of axion inflation based on decay constant alignment from a string-theoretic and quantum gravitational perspective. In particular, we investigate the prospects for alignment and â€anti-alignmentâ€™ of C{sub 4} axion decay constants in type IIB string theory, deriving a strict no-go result in the latter case. We discuss the relationship of axion decay constants to the weak gravity conjecture and demonstrate agreement between our string-theoretic constraints and those coming from the â€generalizedâ€™ weak gravity conjecture. Finally, we consider a particular model of decay constant alignment in which the potential of C{sub 4} axions in type IIB compactifications on a Calabi-Yau three-fold is dominated by contributions from D7-branes, pointing out that this model evades some of the challenges derived earlier in our paper but is highly constrained by other geometric considerations.
ONE NEVADA LINE | Department of Energy
ONE NEVADA LINE ONE NEVADA LINE DOE-LPOProject-PostersSTOR-TRSMOne-Nevada-Line.pdf (323.38 KB) More Documents & Publications STEPHENTOWN SPINDLE CX-011989: Categorical Exclusion ...
Structure formation in a nonlocally modified gravity model
Park, Sohyun; Dodelson, Scott
2013-01-01
We study a nonlocally modified gravity model proposed by Deser and Woodard which gives an explanation for current cosmic acceleration. By deriving and solving the equations governing the evolution of the structure in the Universe, we show that this model predicts a pattern of growth that differs from standard general relativity (+dark energy) at the 10-30% level. These differences will be easily probed by the next generation of galaxy surveys, so the model should be tested shortly.
Confidence limits and their errors
Rajendran Raja
2002-03-22
Confidence limits are common place in physics analysis. Great care must be taken in their calculation and use especially in cases of limited statistics. We introduce the concept of statistical errors of confidence limits and argue that not only should limits be calculated but also their errors in order to represent the results of the analysis to the fullest. We show that comparison of two different limits from two different experiments becomes easier when their errors are also quoted. Use of errors of confidence limits will lead to abatement of the debate on which method is best suited to calculate confidence limits.
NETL LINES OF DEMARCATION 09282012
U.S. Department of Energy (DOE) - all webpages (Extended Search)
LINES OF DEMARCATION September 28, 2012 Contact: Site Operations Division or ESS&H Division with Questions The oversight, upkeep, and segregation of NETL infrastructure components, including lines of demarcation between ORD and OIO, will be as follows: 1. Common utility headers including gas compression systems that enter or exit the site will be maintained by the Office of Institutional Operations (OIO). A line of responsibility demarcation between OIO and ORD will be established at the
Quantum Gravity corrections and entropy at the Planck time
Basilakos, Spyros; Vagenas, Elias C.; Das, Saurya E-mail: saurya.das@uleth.ca
2010-09-01
We investigate the effects of Quantum Gravity on the Planck era of the universe. In particular, using different versions of the Generalized Uncertainty Principle and under specific conditions we find that the main Planck quantities such as the Planck time, length, mass and energy become larger by a factor of order 10?10{sup 4} compared to those quantities which result from the Heisenberg Uncertainty Principle. However, we prove that the dimensionless entropy enclosed in the cosmological horizon at the Planck time remains unchanged. These results, though preliminary, indicate that we should anticipate modifications in the set-up of cosmology since changes in the Planck era will be inherited even to the late universe through the framework of Quantum Gravity (or Quantum Field Theory) which utilizes the Planck scale as a fundamental one. More importantly, these corrections will not affect the entropic content of the universe at the Planck time which is a crucial element for one of the basic principles of Quantum Gravity named Holographic Principle.
The observational status of Galileon gravity after Planck
Barreira, Alexandre; Li, Baojiu; Baugh, Carlton M.; Pascoli, Silvia E-mail: baojiu.li@durham.ac.uk E-mail: silvia.pascoli@durham.ac.uk
2014-08-01
We use the latest CMB data from Planck, together with BAO measurements, to constrain the full parameter space of Galileon gravity. We constrain separately the three main branches of the theory known as the Cubic, Quartic and Quintic models, and find that all yield a very good fit to these data. Unlike in ?CDM, the Galileon model constraints are compatible with local determinations of the Hubble parameter and predict nonzero neutrino masses at over 5? significance. We also identify that the low l part of the CMB lensing spectrum may be able to distinguish between ?CDM and Galileon models. In the Cubic model, the lensing potential deepens at late times on sub-horizon scales, which is at odds with the current observational suggestion of a positive ISW effect. Compared to ?CDM, the Quartic and Quintic models predict less ISW power in the low l region of the CMB temperature spectrum, and as such are slightly preferred by the Planck data. We illustrate that residual local modifications to gravity in the Quartic and Quintic models may render the Cubic model as the only branch of Galileon gravity that passes Solar System tests.
Cosmological perturbation in f(T) gravity revisited
Izumi, Keisuke; Ong, Yen Chin E-mail: ongyenchin@member.ams.org
2013-06-01
We perform detailed investigation of cosmological perturbations in f(T) theory of gravity coupled with scalar field. Our work emphasizes on the way to gauge fix the theory and we examine all possible modes of perturbations up to second order. The analysis includes pseudoscalar and pseudovector modes in addition to the usual scalar, vector, and tensor modes. We find no gravitational propagating degree of freedom in the scalar, pseudoscalar, vector, as well as pseudovector modes. In addition, we find that the scalar and tensor perturbations have exactly the same form as their counterparts in usual general relativity with scalar field, except that the factor of reduced Planck mass squared M{sub pl}{sup 2}?1/(8?G) that occurs in the latter has now been replaced by an effective time-dependent gravitational coupling ?2(df/dT)|{sub T=T{sub 0}}, with T{sub 0} being the background torsion scalar. The absence of extra degrees of freedom of f(T) gravity at second order linear perturbation indicates that f(T) gravity is highly nonlinear. Consequently one cannot conclusively analyze stability of the theory without performing nonlinear analysis that can reveal the propagation of the extra degrees of freedom.
Nonlinear structure formation in the cubic Galileon gravity model
Barreira, Alexandre; Li, Baojiu; Hellwing, Wojciech A.; Baugh, Carlton M.; Pascoli, Silvia E-mail: baojiu.li@durham.ac.uk E-mail: c.m.baugh@durham.ac.uk
2013-10-01
We model the linear and nonlinear growth of large scale structure in the Cubic Galileon gravity model, by running a suite of N-body cosmological simulations using the ECOSMOG code. Our simulations include the Vainshtein screening effect, which reconciles the Cubic Galileon model with local tests of gravity. In the linear regime, the amplitude of the matter power spectrum increases by ? 20% with respect to the standard ?CDM model today. The modified expansion rate accounts for ? 15% of this enhancement, while the fifth force is responsible for only ? 5%. This is because the effective unscreened gravitational strength deviates from standard gravity only at late times, even though it can be twice as large today. In the nonlinear regime (k?>0.1h Mpc{sup ?1}), the fifth force leads to only a modest increase (?<8%) in the clustering power on all scales due to the very efficient operation of the Vainshtein mechanism. Such a strong effect is typically not seen in other models with the same screening mechanism. The screening also results in the fifth force increasing the number density of halos by less than 10%, on all mass scales. Our results show that the screening does not ruin the validity of linear theory on large scales which anticipates very strong constraints from galaxy clustering data. We also show that, whilst the model gives an excellent match to CMB data on small angular scales (l?>50), the predicted integrated Sachs-Wolfe effect is in tension with Planck/WMAP results.
Affine group formulation of the Standard Model coupled to gravity
Chou, Ching-Yi; Ita, Eyo; Soo, Chopin
2014-04-15
In this work we apply the affine group formalism for four dimensional gravity of Lorentzian signature, which is based on Klauder’s affine algebraic program, to the formulation of the Hamiltonian constraint of the interaction of matter and all forces, including gravity with non-vanishing cosmological constant ?, as an affine Lie algebra. We use the hermitian action of fermions coupled to gravitation and Yang–Mills theory to find the density weight one fermionic super-Hamiltonian constraint. This term, combined with the Yang–Mills and Higgs energy densities, are composed with York’s integrated time functional. The result, when combined with the imaginary part of the Chern–Simons functional Q, forms the affine commutation relation with the volume element V(x). Affine algebraic quantization of gravitation and matter on equal footing implies a fundamental uncertainty relation which is predicated upon a non-vanishing cosmological constant. -- Highlights: •Wheeler–DeWitt equation (WDW) quantized as affine algebra, realizing Klauder’s program. •WDW formulated for interaction of matter and all forces, including gravity, as affine algebra. •WDW features Hermitian generators in spite of fermionic content: Standard Model addressed. •Constructed a family of physical states for the full, coupled theory via affine coherent states. •Fundamental uncertainty relation, predicated on non-vanishing cosmological constant.
Halo model and halo properties in Galileon gravity cosmologies
Barreira, Alexandre; Li, Baojiu; Hellwing, Wojciech A.; Baugh, Carlton M.; Lombriser, Lucas; Pascoli, Silvia E-mail: baojiu.li@durham.ac.uk E-mail: llo@roe.ac.uk E-mail: silvia.pascoli@durham.ac.uk
2014-04-01
We investigate the performance of semi-analytical modelling of large-scale structure in Galileon gravity cosmologies using results from N-body simulations. We focus on the Cubic and Quartic Galileon models that provide a reasonable fit to CMB, SNIa and BAO data. We demonstrate that the Sheth-Tormen mass function and linear halo bias can be calibrated to provide a very good fit to our simulation results. We also find that the halo concentration-mass relation is well fitted by a power law. The nonlinear matter power spectrum computed in the halo model approach is found to be inaccurate in the mildly nonlinear regime, but captures reasonably well the effects of the Vainshtein screening mechanism on small scales. In the Cubic model, the screening mechanism hides essentially all of the effects of the fifth force inside haloes. In the case of the Quartic model, the screening mechanism leaves behind residual modifications to gravity, which make the effective gravitational strength time-varying and smaller than the standard value. Compared to normal gravity, this causes a deficiency of massive haloes and leads to a weaker matter clustering on small scales. For both models, we show that there are realistic halo occupation distributions of Luminous Red Galaxies that can match both the observed large-scale clustering amplitude and the number density of these galaxies.
The role of vector fields in modified gravity scenarios
Tasinato, Gianmassimo; Koyama, Kazuya; Khosravi, Nima E-mail: kazuya.koyama@port.ac.uk
2013-11-01
Gravitational vector degrees of freedom typically arise in many examples of modified gravity models. We start to systematically explore their role in these scenarios, studying the effects of coupling gravitational vector and scalar degrees of freedom. We focus on set-ups that enjoy a Galilean symmetry in the scalar sector and an Abelian gauge symmetry in the vector sector. These symmetries, together with the requirement that the equations of motion contain at most two space-time derivatives, only allow for a small number of operators in the Lagrangian for the gravitational fields. We investigate the role of gravitational vector fields for two broad classes of phenomena that characterize modified gravity scenarios. The first is self-acceleration: we analyze in general terms the behavior of vector fluctuations around self-accelerating solutions, and show that vanishing kinetic terms of vector fluctuations lead to instabilities on cosmological backgrounds. The second phenomenon is the screening of long range fifth forces by means of Vainshtein mechanism. We show that if gravitational vector fields are appropriately coupled to a spherically symmetric source, they can play an important role for defining the features of the background solution and the scale of the Vainshtein radius. Our general results can be applied to any concrete model of modified gravity, whose low-energy vector and scalar degrees of freedom satisfy the symmetry requirements that we impose.
Geological model for oil gravity variations in Oriente Basin, Ecuador
Dashwood, M.F.; Abbotts, I.L.
1988-01-01
The Oriente basin is one of the major productive Subandean basins. Most of the fields produce 29/sup 0/-33/sup 0/ API paraffinic oils, but oils have been discovered with gravities ranging from 10/sup 0/to 35/sup 0/ API. All the oils have been recovered from multiple middle to Late Cretaceous sandstone reservoirs (Hollin and Napo Formations). Wells display a variety of oil gravities by reservoir. The origin of the Oriente oils is problematical and controversial, but structural, geochemical, and well evidence suggest a vast oil kitchen west of the present Andean foothills that was mature for oil generation by at least early Tertiary. Oil analyses indicate a single family of oils is present. Oil gravity variations can be explained systematically in terms of the various alteration processes suffered by the oil in each reservoir. Intermittent early Andean uplift (latest Cretaceous to Mid-Eocene) resulted in biodegradation and water-washing of oils, particularly in the uppermost Napo reservoirs. The main Andean orogeny (Pliocene) uplifted the Hollin reservoir to outcrop in the west, and tilted the basin down to the south. This movement resulted in water washing or flushing of the Hollin aquifer and a phase of northward remigration of oil. Late Andean structures postdated primary oil migration. Almost all structures displaying growth during the Late Cretaceous to early Eocene have been oil bearing, but some, particularly those located on the present-day basin flanks, were later severely biodegraded or breached.
Stability of spherically symmetric solutions in modified theories of gravity
Seifert, Michael D.
2007-09-15
In recent years, a number of alternative theories of gravity have been proposed as possible resolutions of certain cosmological problems or as toy models for possible but heretofore unobserved effects. However, the implications of such theories for the stability of structures such as stars have not been fully investigated. We use our 'generalized variational principle', described in a previous work [M. D. Seifert and R. M. Wald, Phys. Rev. D 75, 084029 (2007)], to analyze the stability of static spherically symmetric solutions to spherically symmetric perturbations in three such alternative theories: Carroll et al.'s f(R) gravity, Jacobson and Mattingly's 'Einstein-aether theory', and Bekenstein's TeVeS theory. We find that in the presence of matter, f(R) gravity is highly unstable; that the stability conditions for spherically symmetric curved vacuum Einstein-aether backgrounds are the same as those for linearized stability about flat spacetime, with one exceptional case; and that the 'kinetic terms' of vacuum TeVeS theory are indefinite in a curved background, leading to an instability.
Wilds, R.B.; Ames, J.R.
1957-09-24
The line-above-ground attenuator provides a continuously variable microwave attenuator for a coaxial line that is capable of high attenuation and low insertion loss. The device consists of a short section of the line-above- ground plane type transmission lime, a pair of identical rectangular slabs of lossy material like polytron, whose longitudinal axes are parallel to and indentically spaced away from either side of the line, and a geared mechanism to adjust amd maintain this spaced relationship. This device permits optimum fineness and accuracy of attenuator control which heretofore has been difficult to achieve.
Emergency pipe line repair connects subsea pipe lines
Lerique, M.P.; Thiberge, P. ); Wright, N. )
1990-11-01
Emergency repair of any subsea line pipe must form a high-integrity, metal-to-metal seal. This paper presents a remote, diverless repair system that utilizes master flanges, a connector and a spool piece to repair line pipe in deep offshore waters.
The limits of the nuclear landscape
Nazarewicz, Witold; Erler, J.; Birge, N.; Kortelainen, E. M.; Olsen, E.; Perhac, A.; Stoitsov, M.
2012-01-01
In 2011, 100 new nuclides were discovered1. They joined the approximately 3,000 stable and radioactive nuclides that either occur naturally on Earth or are synthesized in the laboratory2,3. Every atomic nucleus, characterized by a specific number of protons and neutrons, occupies a spot on the chart of nuclides, which is bounded by drip lines indicating the values of neutron and proton number at which nuclear binding ends. The placement of the neutron drip line for the heavier elements is based on theoretical predictions using extreme extrapolations, and so is uncertain. However, it is not known how uncertain it is or how many protons and neutrons can be bound in a nucleus. Here we estimate these limits of the nuclear landscape and provide statistical and systematic uncertainties for our predictions. We use nuclear density functional theory, several Skyrme interactions and high-performance computing, and find that the number of bound nuclides with between 2 and 120 protons is around 7,000. We find that extrapolations for drip-line positions and selected nuclear properties, including neutron separation energies relevant to astrophysical processes, are very consistent between the models used.
Adjustable direct current and pulsed circuit fault current limiter
Boenig, Heinrich J.; Schillig, Josef B.
2003-09-23
A fault current limiting system for direct current circuits and for pulsed power circuit. In the circuits, a current source biases a diode that is in series with the circuits' transmission line. If fault current in a circuit exceeds current from the current source biasing the diode open, the diode will cease conducting and route the fault current through the current source and an inductor. This limits the rate of rise and the peak value of the fault current.
DISSOLVED CONCENTRATION LIMITS OF RADIOACTIVE ELEMENTS
NA
2004-11-22
The purpose of this study is to evaluate dissolved concentration limits (also referred to as solubility limits) of elements with radioactive isotopes under probable repository conditions, based on geochemical modeling calculations using geochemical modeling tools, thermodynamic databases, field measurements, and laboratory experiments. The scope of this modeling activity is to predict dissolved concentrations or solubility limits for 14 elements with radioactive isotopes (actinium, americium, carbon, cesium, iodine, lead, neptunium, plutonium, protactinium, radium, strontium, technetium, thorium, and uranium) important to calculated dose. Model outputs for uranium, plutonium, neptunium, thorium, americium, and protactinium are in the form of tabulated functions with pH and log (line integral) CO{sub 2} as independent variables, plus one or more uncertainty terms. The solubility limits for the remaining elements are either in the form of distributions or single values. The output data from this report are fundamental inputs for Total System Performance Assessment for the License Application (TSPA-LA) to determine the estimated release of these elements from waste packages and the engineered barrier system. Consistent modeling approaches and environmental conditions were used to develop solubility models for all of the actinides. These models cover broad ranges of environmental conditions so that they are applicable to both waste packages and the invert. Uncertainties from thermodynamic data, water chemistry, temperature variation, and activity coefficients have been quantified or otherwise addressed.
Microtearing turbulence: Magnetic braiding and disruption limit
Firpo, Marie-Christine
2015-12-15
A realistic reduced model involving a large poloidal spectrum of microtearing modes is used to probe the existence of some stochasticity of magnetic field lines. Stochasticity is shown to occur even for the low values of the magnetic perturbation Î´B/B devoted to magnetic turbulence that have been experimentally measured. Because the diffusion coefficient may strongly depend on the radial (or magnetic-flux) coordinate, being very low near some resonant surfaces, and because its evaluation implicitly makes a normal diffusion hypothesis, one turns to another indicator appropriate to diagnose the confinement: the mean residence time of magnetic field lines. Their computation in the microturbulence frame points to the existence of a disruption limit, namely of a critical order of magnitude of Î´B/B above which stochasticity is no longer benign yet, leads to a macroscopic loss of confinement in some tens to hundred of electron toroidal excursions. Since the level of magnetic turbulence Î´B/B has been measured to grow with the plasma electron density, this would also be a density limit.
Office of Energy Efficiency and Renewable Energy (EERE)
SunLine Transit Agency provides public transit and community services to California's Coachella Valley. The service area is more than 1,100 square miles and includes nine member cities, as well as Riverside County. Over the years, SunLine has pursued an aggressive strategy for implementing clean technologies into its fleet.
Constraints on a f(R) gravity dark energy model with early scaling evolution
Park, Chan-Gyung; Hwang, Jai-chan; Noh, Hyerim E-mail: jchan@knu.ac.kr
2011-09-01
The modified gravity with f(R) = R{sup 1+?} (? > 0) allows a scaling solution where the energy density of gravity sector follows the energy density of the dominant fluid. We present initial conditions of background and perturbation variables during the scaling evolution regime in the modified gravity. As a possible dark energy model we consider a gravity with a form f(R) = R{sup 1+?}+qR{sup ?n} (?1 < n ? 0) where the second term drives the late-time acceleration. We show that our f(R) gravity parameters are very sensitive to the baryon perturbation growth and baryon density power spectrum, and present observational constraints on the model parameters. We consider full perturbations of f(R) gravity. Our analysis suggests that only the parameter space extremely close to the ?CDM model is allowed with ??<5 × 10{sup ?6} and n?>?10{sup ?4}.
COMMENTARY:Limits to adaptation
Preston, Benjamin L
2013-01-01
An actor-centered, risk-based approach to defining limits to social adaptation provides a useful analytic framing for identifying and anticipating these limits and informing debates over society s responses to climate change.
Integration of Full Tensor Gravity and ZTEM Passive Low Frequency EM
Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)
Instruments for Simultaneous Data Acquisition | Department of Energy Full Tensor Gravity and ZTEM Passive Low Frequency EM Instruments for Simultaneous Data Acquisition Integration of Full Tensor Gravity and ZTEM Passive Low Frequency EM Instruments for Simultaneous Data Acquisition Integration of Full Tensor Gravity and ZTEM Passive Low Frequency EM Instruments for Simultaneous Data Acquisition presentation at the April 2013 peer review meeting held in Denver, Colorado.
Plains & Eastern Clean Line Transmission Line - Part 2 Application...
... KB) Appendix 10-E HVDC Scheme Diagram (33.51 KB) Appendix 10-F Shelby Substation and Optima Substation One-Line Drawings (925.73 KB) Appendix 10-J HVDC Specification ...
SSRL Beam Lines Map | Stanford Synchrotron Radiation Lightsource
U.S. Department of Energy (DOE) - all webpages (Extended Search)
SSRL Beam Lines Map Beam Line by Number | Beam Line by Techniques | Photon Source Parameters
Ground Gravity Survey At Blue Mountain Geothermal Area (U.S....
OpenEI (Open Energy Information) [EERE & EIA]
search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At Blue Mountain Geothermal Area (U.S. Geological Survey, 2012) Exploration Activity Details...
Ground Gravity Survey At U.S. West Region (Aiken & Ander, 1981...
OpenEI (Open Energy Information) [EERE & EIA]
and southern Colorado References Carlos L.V. Aiken, Mark E. Ander (1981) A Regional Strategy For Geothermal Exploration With Emphasis On Gravity And Magnetotellurics Additional...
Ground Gravity Survey At Maui Area (DOE GTP) | Open Energy Information
OpenEI (Open Energy Information) [EERE & EIA]
Maui Area (DOE GTP) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At Maui Area (DOE GTP) Exploration Activity Details...
Reduced Gravity Education Flight Opportunity for Students at Minority Serving Institutions
Office of Energy Efficiency and Renewable Energy (EERE)
NASA is offering undergraduate students from Minority Serving Institutions an opportunity to test experiments in microgravity aboard NASA's reduced gravity aircraft.
Ground Gravity Survey At Raft River Geothermal Area (1957-1961...
OpenEI (Open Energy Information) [EERE & EIA]
search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At Raft River Geothermal Area (1957-1961) Exploration Activity Details Location Raft River...
Ground Gravity Survey At Cove Fort Area (Toksoz, Et Al, 2010...
OpenEI (Open Energy Information) [EERE & EIA]
Exploration Activity Details Location Cove Fort Geothermal Area Exploration Technique Ground Gravity Survey Activity Date Usefulness not indicated DOE-funding Unknown Notes We...
Ground Gravity Survey At San Emidio Desert Area (DOE GTP) | Open...
OpenEI (Open Energy Information) [EERE & EIA]
Emidio Desert Area (DOE GTP) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At San Emidio Desert Area (DOE GTP)...
Ground Gravity Survey At Salt Wells Area (Bureau of Land Management...
OpenEI (Open Energy Information) [EERE & EIA]
2009) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At Salt Wells Area (Bureau of Land Management, 2009) Exploration...
Electrical transmission line diametrical retainer
Hall, David R.; Hall, Jr., H. Tracy; Pixton, David; Dahlgren, Scott; Sneddon, Cameron; Briscoe, Michael; Fox, Joe
2004-12-14
The invention is a mechanism for retaining an electrical transmission line. In one embodiment of the invention it is a system for retaining an electrical transmission line within down hole components. In accordance with one aspect of the invention, the system includes a plurality of downhole components, such as sections of pipe in a drill string. The system also includes a coaxial cable running between the first and second end of a drill pipe, the coaxial cable having a conductive tube and a conductive core within it. The invention allows the electrical transmission line to with stand the tension and compression of drill pipe during routine drilling cycles.
Pulse shaping with transmission lines
Wilcox, Russell B.
1987-01-01
A method and apparatus for forming shaped voltage pulses uses passive reflection from a transmission line with nonuniform impedance. The impedance of the reflecting line varies with length in accordance with the desired pulse shape. A high voltage input pulse is transmitted to the reflecting line. A reflected pulse is produced having the desired shape and is transmitted by pulse removal means to a load. Light activated photoconductive switches made of silicon can be utilized. The pulse shaper can be used to drive a Pockels cell to produce shaped optical pulses.
Pulse shaping with transmission lines
Wilcox, R.B.
1985-08-15
A method and apparatus for forming shaped voltage pulses uses passive reflection from a transmission line with nonuniform impedance. The impedance of the reflecting line varies with length in accordance with the desired pulse shape. A high voltage input pulse is transmitted to the reflecting line. A reflected pulse is produced having the desired shape and is transmitted by pulse removal means to a load. Light activated photoconductive switches made of silicon can be utilized. The pulse shaper can be used to drive a Pockels cell to produce shaped optical pulses.
Flavor Universal Resonances and Warped Gravity | Argonne National
U.S. Department of Energy (DOE) - all webpages (Extended Search)
Laboratory Flavor Universal Resonances and Warped Gravity December 6, 2016 3:15PM to 4:15PM Presenter Sungwoo Hong, Maryland University Location Building 362, Room E188 Type Seminar Series HEP Theory Seminar Abstract: Warped higher-dimensional compactifications with "bulk" standard model, or their AdS/CFT dual as the purely 4D scenario of Higgs compositeness and partial compositeness, offer an elegant approach to resolving the electroweak hierarchy problem as well as the origins of
Wheeler-DeWitt equation for brane gravity
Gusin, Pawel
2008-03-15
We consider gravity in the system consisting of the Bogomol'nyi-Prasad-Sommerfield (BPS) D3-brane embedded in a flat background geometry, produced by the solutions of supergravity. The effective action for this system is represented by the sum of the Hilbert-Einstein and Dirac-Born-Infeld actions. We derive the Wheeler-DeWitt equation for this system and obtain analytical solutions in some special cases. We also calculate the tunneling probability from the Planckian size of the D3-brane to the classical regime.
Large Searching for Higher Dimensional Gravity with Neutron Experiments
Frank, Alejandro
2007-10-26
N-dimensional gravity is analized in the context of recent work on 'large' supplementary dimensions. A simple derivation of the compactification radii for additional dimensions in the universe is made, as a function of the Planck and the electro-weak scales. It is argued that the modified gravitational force would give rise to effects that might be within the detection range of dedicated neutron experiments. An analysis suggests that neutron scattering off atomic nuclei with null spin may provide an experimental test for these ideas.
Translation invariant time-dependent massive gravity: Hamiltonian analysis
Mourad, Jihad; Steer, Daničle A.; Noui, Karim E-mail: karim.noui@lmpt.univ-tours.fr
2014-09-01
The canonical structure of the massive gravity in the first order moving frame formalism is studied. We work in the simplified context of translation invariant fields, with mass terms given by general non-derivative interactions, invariant under the diagonal Lorentz group, depending on the moving frame as well as a fixed reference frame. We prove that the only mass terms which give 5 propagating degrees of freedom are the dRGT mass terms, namely those which are linear in the lapse. We also complete the Hamiltonian analysis with the dynamical evolution of the system.
Self-gravity in neutrino-dominated accretion disks
Liu, Tong; Yu, Xiao-Fei; Gu, Wei-Min; Lu, Ju-Fu
2014-08-10
We present the effects of self-gravity on the vertical structure and neutrino luminosity of the neutrino-dominated accretion disks in cylindrical coordinates. It is found that significant changes of the structure appear in the outer region of the disk, especially for high accretion rates (e.g., ? 1 M{sub ?} s{sup –1}), and thus cause the slight increase in the neutrino luminosity. Furthermore, the gravitational instability of the disk is reviewed by the vertical distribution of the Toomre parameter, which may account for the late-time flares in gamma-ray bursts and the extended emission in short-duration gamma-ray bursts.
Condensation during gravity driven ECC: Experiments with PACTEL
Munther, R.; Kalli, H.; Kouhia, J.
1995-09-01
This paper provides the results of the second series of gravity driven emergency core cooling (ECC) experiments with PACTEL (Parallel Channel Test Loop). The simulated accident was a small break loss-of-coolant accident (SBLOCA) with a break in a cold leg. The ECC flow was provided from a core makeup tank (CMT) located at a higher elevation than the main part of the primary system. The CMT was pressurized with pipings from the pressurizer and a cold leg. The tests indicated that steam condensation in the CMT can prevent ECC and lead to core uncovery.
Properties of solar gravity mode signals in total irradiance observations
Kroll, R.J.; Chen, J.; Hill, H.A.
1988-01-01
Further evidence has been found that a significant fraction of the gravity mode power density in the total irradiance observations appears in sidebands of classified eigenfrequencies. These sidebands whose amplitudes vary from year to year are interpreted as harmonics of the rotational frequencies of the nonuniform solar surface. These findings are for non axisymmetric modes and corroborate the findings of Kroll, Hill and Chen for axisymmetric modes. It is demonstrated the the generation of the sidebands lifts the usual restriction on the parity of the eigenfunctions for modes detectable in total irradiance observations. 14 refs.
Noncommutative scalar field minimally coupled to nonsymmetric gravity
Kouadik, S.; Sefai, D.
2012-06-27
We construct a non-commutative non symmetric gravity minimally coupled model (the star product only couples matter). We introduce the action for the system considered namely a non-commutative scalar field propagating in a nontrivial gravitational background. We expand the action in powers of the anti-symmetric field and the graviton to second order adopting the assumption that the scalar is weekly coupled to the graviton. We compute the one loop radiative corrections to the self-energy of a scalar particle.
Is Cosmic Acceleration Telling Us Something About Gravity?
Trodden, Mark [Syracuse University, Syracuse, New York, United States
2016-07-12
Among the possible explanations for the observed acceleration of the universe, perhaps the boldest is the idea that new gravitational physics might be the culprit. In this colloquium I will discuss some of the challenges of constructing a sensible phenomenological extension of General Relativity, give examples of some candidate models of modified gravity and survey existing observational constraints on this approach. I will conclude by discussing how we might hope to distinguish between modifications of General Relativity and dark energy as competing hypotheses to explain cosmic acceleration.
Means for limiting and ameliorating electrode shorting
Van Konynenburg, Richard A.; Farmer, Joseph C.
1999-01-01
A fuse and filter arrangement for limiting and ameliorating electrode shorting in capacitive deionization water purification systems utilizing carbon aerogel, for example. This arrangement limits and ameliorates the effects of conducting particles or debonded carbon aerogel in shorting the electrodes of a system such as a capacitive deionization water purification system. This is important because of the small interelectrode spacing and the finite possibility of debonding or fragmentation of carbon aerogel in a large system. The fuse and filter arrangement electrically protect the entire system from shutting down if a single pair of electrodes is shorted and mechanically prevents a conducting particle from migrating through the electrode stack, shorting a series of electrode pairs in sequence. It also limits the amount of energy released in a shorting event. The arrangement consists of a set of circuit breakers or fuses with one fuse or breaker in the power line connected to one electrode of each electrode pair and a set of screens of filters in the water flow channels between each set of electrode pairs.
Means for limiting and ameliorating electrode shorting
Konynenburg, R.A. van; Farmer, J.C.
1999-11-09
A fuse and filter arrangement is described for limiting and ameliorating electrode shorting in capacitive deionization water purification systems utilizing carbon aerogel, for example. This arrangement limits and ameliorates the effects of conducting particles or debonded carbon aerogel in shorting the electrodes of a system such as a capacitive deionization water purification system. This is important because of the small interelectrode spacing and the finite possibility of debonding or fragmentation of carbon aerogel in a large system. The fuse and filter arrangement electrically protect the entire system from shutting down if a single pair of electrodes is shorted and mechanically prevents a conducting particle from migrating through the electrode stack, shorting a series of electrode pairs in sequence. It also limits the amount of energy released in a shorting event. The arrangement consists of a set of circuit breakers or fuses with one fuse or breaker in the power line connected to one electrode of each electrode pair and a set of screens of filters in the water flow channels between each set of electrode pairs.
NETL LINES OF DEMARCATION 09282012
U.S. Department of Energy (DOE) - all webpages (Extended Search)
A line of responsibility demarcation between OIO and ORD will be established at the shutoff on the branch leading to or from an R&D project or laboratory area. OIO will install a ...
Reindel, John
1990-01-01
A fin line circuit card containing a fin line slot feeds a dipole antenna ich extends a quarterwave outside the waveguide and provides an energy beam focal point at or near the open end of the waveguide. The dipole antenna thus maintains a wide and nearly constant beamwidth, low VSWR and a circular symmetric radiation pattern for use in electronic warfare direction finding and surveillance applications.
Letter from Deputy Secretary Poneman to Clean Line Energy Regarding...
Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)
Line: Comment from Ms. Schroeder Plains and Eastern Clean Line Transmission Line: Comment from Mr. Zuniga Plains and Eastern Clean Line Transmission Line: Comment from Mr. Cain...
Simulating the quartic Galileon gravity model on adaptively refined meshes
Li, Baojiu; Barreira, Alexandre; Baugh, Carlton M.; Hellwing, Wojciech A.; Koyama, Kazuya; Zhao, Gong-Bo; Pascoli, Silvia E-mail: baojiu.li@durham.ac.uk E-mail: wojciech.hellwing@durham.ac.uk E-mail: silvia.pascoli@durham.ac.uk
2013-11-01
We develop a numerical algorithm to solve the high-order nonlinear derivative-coupling equation associated with the quartic Galileon model, and implement it in a modified version of the ramses N-body code to study the effect of the Galileon field on the large-scale matter clustering. The algorithm is tested for several matter field configurations with different symmetries, and works very well. This enables us to perform the first simulations for a quartic Galileon model which provides a good fit to the cosmic microwave background (CMB) anisotropy, supernovae and baryonic acoustic oscillations (BAO) data. Our result shows that the Vainshtein mechanism in this model is very efficient in suppressing the spatial variations of the scalar field. However, the time variation of the effective Newtonian constant caused by the curvature coupling of the Galileon field cannot be suppressed by the Vainshtein mechanism. This leads to a significant weakening of the strength of gravity in high-density regions at late times, and therefore a weaker matter clustering on small scales. We also find that without the Vainshtein mechanism the model would have behaved in a completely different way, which shows the crucial role played by nonlinearities in modified gravity theories and the importance of performing self-consistent N-body simulations for these theories.
Wormholes, emergent gauge fields, and the weak gravity conjecture
Harlow, Daniel
2016-01-20
This paper revisits the question of reconstructing bulk gauge fields as boundary operators in AdS/CFT. In the presence of the ormhole dual to the thermo field double state of two CFTs, the existence of bulk gauge fields is in some tension with the microscopic tensor factorization of the Hilbert space. Here, I explain how this tension can be resolved by splitting the gauge field into charged constituents, and I argue that this leads to a new argument for the "principle of completeness", which states that the charge lattice of a gauge theory coupled to gravity must be fully populated. ImoreÂ Â» also claim that it leads to a new motivation for (and a clarification of) the "weak gravity conjecture", which I interpret as a strengthening of this principle. This setup gives a simple example of a situation where describing low-energy bulk physics in CFT language requires knowledge of high-energy bulk physics. Furthermore, this contradicts to some extent the notion of "effective conformal field theory", but in fact is an expected feature of the resolution of the black hole information problem. An analogous factorization issue exists also for the gravitational field, and I comment on several of its implications for reconstructing black hole interiors and the emergence of spacetime more generally.Â«Â less
Confronting DGP braneworld gravity with cosmico observations after Planck data
Xu, Lixin
2014-02-01
The normal branch of Dvali-Gabadadze-Porrati braneworld gravity with brane tension is confronted by the currently available cosmic observations from the geometrical and dynamical perspectives. On the geometrical side, the type Ia supernova as standard candle, the baryon acoustic oscillation as standard ruler and the cosmic microwave background measurement from the first released 15.5 months data were used to fix the background evolutions. On the dynamical side, the redshift space distortion data will be used to determine the evolution of the matter perturbation. Through a Markov chain Monte Carlo analysis, we found the dimensionless crossover scale ?{sub r{sub c}} = 1/(4H{sup 2}{sub 0}r{sup 2}{sub c}) = 0.00183{sub ?0.00183}{sup +0.000338} in a spatially flat normal branch of Dvali-Gabadadze-Porrati braneworld. This result suggests that the crossover scale r{sub c} should be around 12H{sup ?1}{sub 0} which is consistent with the previous result r{sub c} > 3H{sup ?1}{sub 0} and greater. It also implies that the five-dimensional gravity effect is weak to be observed in H{sup ?1}{sub 0} scale.
Two-dimensional gravity with a dynamical aether
Eling, Christopher; Jacobson, Ted
2006-10-15
We investigate the two-dimensional behavior of gravity coupled to a dynamical unit timelike vector field, i.e. ''Einstein-aether theory.'' The classical solutions of this theory in two dimensions depend on one coupling constant. When this coupling is positive the only solutions are (i) flat spacetime with constant aether (ii) de Sitter or anti-de Sitter spacetimes with a uniformly accelerated unit vector invariant under a two-dimensional subgroup of SO(2,1) generated by a boost and a null rotation, and (iii) a nonconstant curvature spacetime that has no Killing symmetries and contains singularities. In this case the sign of the curvature is determined by whether the coupling is less or greater than one. When instead the coupling is negative only solutions (i) and (iii) are present. This classical study of the behavior of Einstein-aether theory in 1+1 dimensions may provide a starting point for further investigations into semiclassical and fully quantum toy models of quantum gravity with a dynamical preferred frame.
Investigation of density limit processes in DIII-D
Maingi, R.; Mahdavi, M.A.; Petrie, T.W.
1999-02-01
A series of experiments has been conducted in DIII-D to investigate density-limiting processes. The authors have studied divertor detachment and MARFEs on closed field lines and find semi-quantitative agreement with theoretical calculations of onset conditions. They have shown that the critical density for MARFE onset at low edge temperature scales as I{sub p}/a{sup 2}, i.e. similar to Greenwald scaling. They have also shown that the scaling of the critical separatrix density with heating power at partial detachment onset agrees with Borass` model. Both of these processes yield high edge density limits for reactors such as ITER. By using divertor pumping and pellet fueling they have avoided these and other processes and accessed densities > 1.5{times} Greenwald limit scaling with H-mode confinement, demonstrating that the Greenwald limit is not a fundamental limit on the core density.
PURAC Limited | Open Energy Information
OpenEI (Open Energy Information) [EERE & EIA]
technology and project management company in the environment sector and specialising in water, wastewater and municpal waste treatment. References: PURAC Limited1 This article...
Lysanda Limited | Open Energy Information
OpenEI (Open Energy Information) [EERE & EIA]
CM8 3GA Product: US-based vehicle engineering consultancy with a technology capable of playing a role in vehicle emissions management. References: Lysanda Limited1 This...
Solfex Limited | Open Energy Information
OpenEI (Open Energy Information) [EERE & EIA]
Jump to: navigation, search Name: Solfex Limited Address: Energy Arena Bannister Hall Works Off Shop Lane, Higher Walton Preston, Lancashire PR5 4DZ Place: Preston, United...
FUEL CASK IMPACT LIMITER VULNERABILITIES
Leduc, D; Jeffery England, J; Roy Rothermel, R
2009-02-09
Cylindrical fuel casks often have impact limiters surrounding just the ends of the cask shaft in a typical 'dumbbell' arrangement. The primary purpose of these impact limiters is to absorb energy to reduce loads on the cask structure during impacts associated with a severe accident. Impact limiters are also credited in many packages with protecting closure seals and maintaining lower peak temperatures during fire events. For this credit to be taken in safety analyses, the impact limiter attachment system must be shown to retain the impact limiter following Normal Conditions of Transport (NCT) and Hypothetical Accident Conditions (HAC) impacts. Large casks are often certified by analysis only because of the costs associated with testing. Therefore, some cask impact limiter attachment systems have not been tested in real impacts. A recent structural analysis of the T-3 Spent Fuel Containment Cask found problems with the design of the impact limiter attachment system. Assumptions in the original Safety Analysis for Packaging (SARP) concerning the loading in the attachment bolts were found to be inaccurate in certain drop orientations. This paper documents the lessons learned and their applicability to impact limiter attachment system designs.
LANSCE Beam Current Limiter (XL)
Gallegos, F.R.; Hall, M.J.
1997-01-01
The Radiation Security System (RSS) at the Los Alamos Neutron Science Center (LANSCE) is an engineered safety system that provides personnel protection from prompt radiation due to accelerated proton beams. The Beam Current Limiter (XL), as an active component of the RSS, limits the maximum average current in a beamline, thus the current available for a beam spill accident. Exceeding the pre-set limit initiates action by the RSS to mitigate the hazard (insertion of beam stoppers in the low energy beam transport). The beam limiter is an electrically isolated, toroidal transformer and associated electronics. The device was designed to continuously monitor beamline currents independent of any external timing. Fail-safe operation was a prime consideration in its development. Fail-safe operation is defined as functioning as intended (due to redundant circuitry), functioning with a more sensitive fault threshold, or generating a fault condition. This report describes the design philosophy, hardware, implementation, operation, and limitations of the device.
U.S. Department of Energy (DOE) - all webpages (Extended Search)
Beam Line Support | Floor Support | Administrative Support SPEAR3 Beam Line Availability Beam Line BL Type Technique(s) Status 1-4 X-ray Small and Wide Angle X-ray Scattering Open 1-5 MC MAD, Monochromatic Open 2-1 X-ray Powder Diffraction Open 2-2 X-ray Michromachining, Topography, White Beam, LIGA Down 2-3 X-ray XAS, Instrumentation development and Calibration Open 4-1 X-ray XAS, XSW Re-opens 2008 4-2 X-ray SMB Small Angle X-ray Scattering/Diffraction Re-opens 2008 4-3 X-ray XAS Re-opens 2008
Jaffe, Todd
Validation of Innovative Exploration Technologies for Newberry Volcano: Raw data used to prepare the Gravity Report by Zonge 2012
Jaffe, Todd
2012-01-01
Validation of Innovative Exploration Technologies for Newberry Volcano: Raw data used to prepare the Gravity Report by Zonge 2012
Impact Limiter Tests of Four Commonly Used Materials And Limiter...
Office of Scientific and Technical Information (OSTI)
... of four impact limiter materials was tested at four different load rates, quasi-statically, 44 feet per second (ftjs), (a 9 meter drop test per lOCF71), 33 fts and 22 fts. ...
Forties oil line replacement overcomes sandwave challenge
Steel, W.J.M.; Imglis, R. )
1991-03-06
A major new 36-in., oil-export pipeline has been installed in the North Sea between the Forties field and Cruden Bay on the U.K. mainland. Designing and installing the line involved solving problems caused by sandwaves in the nearshore segment of the route. The Forties pipeline system covers offshore and land pipelines between the Forties field and the Firth of Forth tanker loading terminal and incorporates oil transportation, stabilization-gas separation, processing, and storage. The pipeline is used as part of an integrated oil and gas liquid gathering system from the central North Sea. Oil and gas liquids from other offshore fields are connected by subsea pipelines and riser to the Forties Charlie platform. Inspection of the existing 32-in. offshore pipeline had indicated signs of corrosion which would prevent the system from operating economically as future demands increased. In addition, when the line was commissioned in 1975, it was not envisioned that it would eventually carry crude from several other fields, which will come onstream this decade. The decision to lay a new 36-in. sealine reflects this need for increased capacity to ensure that the Forties pipeline system continues as a major carrier of oil and gas liquids well into the next century. Corrosion monitoring and inspection of the 32-in. line led to sections of the topside pipework being replaced in 1985 and the top section of the rise in 1987. The corrosion also resulted in the pipeline maximum allowable operating pressure (MAOP) being limited to 115 barg (1,668 psig) from 129 barg (1,871 psig).
A probabilistic approach to calculating AC induction levels on power line collocated pipelines
Dabkowski, J. [Electro Sciences, Inc., Crystal Lake, IL (United States)
1995-12-01
For calculating induced voltage levels on pipelines paralleling overhead power lines available computational methods assume that the line circuit currents are balanced, i.e., equal. In this paper probabilistic computational methods are used to calculate induction levels for the more realistic assumption that the line currents carry a small randomly fluctuating component, and therefore, are unbalanced. Results show that limiting consideration to the balanced currents case can result in substantially underestimated induced voltage levels on the pipeline.
Statistical line-by-line model for atomic spectra in intermediate...
Office of Scientific and Technical Information (OSTI)
Statistical line-by-line model for atomic spectra in intermediate coupling Citation Details In-Document Search Title: Statistical line-by-line model for atomic spectra in ...
X-ray line polarization spectroscopy of Li-like satellite line...
Office of Scientific and Technical Information (OSTI)
X-ray line polarization spectroscopy of Li-like satellite line spectra Citation Details In-Document Search Title: X-ray line polarization spectroscopy of Li-like satellite line ...
Plains and Eastern Clean Line Transmission Line: Comment from Dr. Contreras
Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)
| Department of Energy from Dr. Contreras Plains and Eastern Clean Line Transmission Line: Comment from Dr. Contreras Comment submitted on updated Part 2 application. Comment from Dr. Contreras 6-10-15.pdf (608.36 KB) More Documents & Publications Plains and Eastern Clean Line Transmission Line: Comment from Dr. Contreras Plains and Eastern Clean Line Transmission Line: Comment from Dr. Contreras Plains and Eastern Clean Line Transmission Line: Comment from Dr. Contreras
Nuclear Structure at the Limits
Nazarewicz, W.
1998-01-12
One of the frontiers of today?s nuclear science is the ?journey to the limits? of atomic charge and nuclear mass, of neutron-to-proton ratio, and of angular momentum. The tour to the limits is not only a quest for new, exciting phenomena, but the new data are expected, as well, to bring qualitatively new information about the fundamental properties of the nucleonic many-body system, the nature of the nuclear interaction, and nucleonic correlations at various energy-distance scales. In this series of lectures, current developments in nuclear structure at the limits are discussed from a theoretical perspective, mainly concentrating on medium-mass and heavy nuclei.
Nuclear Structure at the Limits
Nazarewicz, Witold
1997-12-31
One of the frontiers of today`s nuclear science is the ``journey to the limits``: of atomic charge and nuclear mass, of neutron-to-proton ratio, and of angular momentum. The tour to the limits is not only a quest for new, exciting phenomena but the new data are expected, as well, to bring qualitatively new information about the fundamental properties of the nucleonic many-body system, the nature of the nuclear interaction, and nucleonic correlations at various energy-distance scales. In this talk, current developments in nuclear structure at the limits are discussed from a theoretical perspective.
INTERNAL GRAVITY WAVES IN MASSIVE STARS: ANGULAR MOMENTUM TRANSPORT
Rogers, T. M.; Lin, D. N. C.; McElwaine, J. N.; Lau, H. H. B. E-mail: lin@ucolick.org E-mail: hblau@astro.uni-bonn.de
2013-07-20
We present numerical simulations of internal gravity waves (IGW) in a star with a convective core and extended radiative envelope. We report on amplitudes, spectra, dissipation, and consequent angular momentum transport by such waves. We find that these waves are generated efficiently and transport angular momentum on short timescales over large distances. We show that, as in Earth's atmosphere, IGW drive equatorial flows which change magnitude and direction on short timescales. These results have profound consequences for the observational inferences of massive stars, as well as their long term angular momentum evolution. We suggest IGW angular momentum transport may explain many observational mysteries, such as: the misalignment of hot Jupiters around hot stars, the Be class of stars, Ni enrichment anomalies in massive stars, and the non-synchronous orbits of interacting binaries.
Translation invariant time-dependent solutions to massive gravity II
Mourad, J.; Steer, D.A. E-mail: steer@apc.univ-paris7.fr
2014-06-01
This paper is a sequel to JCAP 12 (2013) 004 and is also devoted to translation-invariant solutions of ghost-free massive gravity in its moving frame formulation. Here we consider a mass term which is linear in the vielbein (corresponding to a ?{sub 3} term in the 4D metric formulation) in addition to the cosmological constant. We determine explicitly the constraints, and from the initial value formulation show that the time-dependent solutions can have singularities at a finite time. Although the constraints give, as in the ?{sub 1} case, the correct number of degrees of freedom for a massive spin two field, we show that the lapse function can change sign at a finite time causing a singular time evolution. This is very different to the ?{sub 1} case where time evolution is always well defined. We conclude that the ?{sub 3} mass term can be pathological and should be treated with care.
Thermodynamic behavior of particular f(R,T)-gravity models
Sharif, M. Zubair, M.
2013-08-15
We investigate the thermodynamics at the apparent horizon of the FRW universe in f(R, T) theory in the nonequilibrium description. The laws of thermodynamics are discussed for two particular models of the f(R, T) theory. The first law of thermodynamics is expressed in the form of the Clausius relation T{sub h} dS-circumflex{sub h} = {delta} Q , where {delta}Q is the energy flux across the horizon and dS-circumflex is the entropy production term. Furthermore, the conditions for the generalized second law of thermodynamics to be preserved are established with the constraints of positive temperature and attractive gravity. We illustrate our results for some concrete models in this theory.
The application of Raman laser in gravity measurement and metrology
Ru, Ning; Zhang, Li; Wang, Yu; Fan, Shangchun
2014-05-27
Atom Interferometry is proved to be a potential method for measuring the acceleration of atoms due to Gravity, we are now building a feasible system of cold atom gravimeter, it is based on the atom interferometry technology by coherently manipulating the cold atoms in a fountain (with a height of 1m) with specific Raman lasers, the cold atom wave packet is splitted, combined, and then re-splitted in the process. Then the atomic wave packet will acquire different phase because of the different evolution path. The precise acceleration can be deduced through the precision measurement of atomic interference fringes phase, and this will be a high precision standard of acceleration. At present, the preparation of Raman laser and the precise control of the laser Frequency have been finished, and they have been proved to meet the requirements of the experiment.
Vector field models of modified gravity and the dark sector
Zuntz, J.; Ferreira, P. G.; Zlosnik, T. G; Bourliot, F.; Starkman, G. D.
2010-05-15
We present a comprehensive investigation of cosmological constraints on the class of vector field formulations of modified gravity called generalized Einstein-aether models. Using linear perturbation theory we generate cosmic microwave background and large-scale structure spectra for general parameters of the theory, and then constrain them in various ways. We investigate two parameter regimes: a dark matter candidate where the vector field sources structure formation, and a dark energy candidate where it causes late-time acceleration. We find that the dark matter candidate does not fit the data, and identify five physical problems that can restrict this and other theories of dark matter. The dark energy candidate does fit the data, and we constrain its fundamental parameters; most notably we find that the theory's kinetic index parameter n{sub ae} can differ significantly from its {Lambda}CDM value.
Phenomenology of electrostatically charged droplet combustion in normal gravity
Anderson, Eric K.; Koch, Jeremy A.; Kyritsis, Dimitrios C.
2008-08-15
Experimental findings are provided on the effect of electrostatically charging a fuel on single-burning droplet combustion in normal gravity. It was established that significant modification of the flame morphology and the droplet burning time could be achieved, solely by the droplet charge, without the application of external electric fields. Negative charging of the droplets of mixtures of isooctane with either ethanol or a commercially available anti-static additive generated intense motion of the flame and abbreviated the droplet burning time by as much as 40% for certain blend compositions. Positive charging of the droplets generated almost spherical flames, because electrostatic attraction toward the droplets countered the effect of buoyancy. By comparing combustion of droplets of the same conductivity but different compositions, coupling of electrostatics with combustion chemistry was established. (author)
Self-Consistent Cosmological Simulations of DGP Braneworld Gravity
Schmidt, Fabian; /Chicago U., Astron. Astrophys. Ctr. /KICP, Chicago
2009-09-01
We perform cosmological N-body simulations of the Dvali-Gabadadze-Porrati braneworld model, by solving the full non-linear equations of motion for the scalar degree of freedom in this model, the brane bending mode. While coupling universally to matter, the brane-bending mode has self-interactions that become important as soon as the density field becomes non-linear. These self-interactions lead to a suppression of the field in high-density environments, and restore gravity to General Relativity. The code uses a multi-grid relaxation scheme to solve the non-linear field equation in the quasi-static approximation. We perform simulations of a flat self-accelerating DGP model without cosmological constant. However, the type of non-linear interactions of the brane-bending mode, which are the focus of this study, are generic to a wide class of braneworld cosmologies. The results of the DGP simulations are compared with standard gravity simulations assuming the same expansion history, and with DGP simulations using the linearized equation for the brane bending mode. This allows us to isolate the effects of the non-linear self-couplings of the field which are noticeable already on quasi-linear scales. We present results on the matter power spectrum and the halo mass function, and discuss the behavior of the brane bending mode within cosmological structure formation. We find that, independently of CMB constraints, the self-accelerating DGP model is strongly constrained by current weak lensing and cluster abundance measurements.
Chemometrics/on-line measurements
O'Rourke, P.E. )
1989-11-01
The possible future of on-line analytical-quality measurements for improved process control and more timely safeguards measurements is examined in the light of a current project at Savannah River. A measurement system involving a fiber-optic spectrophotometer and the application of mathematical techniques called chemometrics is described.
Coiled transmission line pulse generators
McDonald, Kenneth Fox
2010-11-09
Methods and apparatus are provided for fabricating and constructing solid dielectric "Coiled Transmission Line" pulse generators in radial or axial coiled geometries. The pour and cure fabrication process enables a wide variety of geometries and form factors. The volume between the conductors is filled with liquid blends of monomers, polymers, oligomers, and/or cross-linkers and dielectric powders; and then cured to form high field strength and high dielectric constant solid dielectric transmission lines that intrinsically produce ideal rectangular high voltage pulses when charged and switched into matched impedance loads. Voltage levels may be increased by Marx and/or Blumlein principles incorporating spark gap or, preferentially, solid state switches (such as optically triggered thyristors) which produce reliable, high repetition rate operation. Moreover, these Marxed pulse generators can be DC charged and do not require additional pulse forming circuitry, pulse forming lines, transformers, or an a high voltage spark gap output switch. The apparatus accommodates a wide range of voltages, impedances, pulse durations, pulse repetition rates, and duty cycles. The resulting mobile or flight platform friendly cylindrical geometric configuration is much more compact, light-weight, and robust than conventional linear geometries, or pulse generators constructed from conventional components. Installing additional circuitry may accommodate optional pulse shape improvements. The Coiled Transmission Lines can also be connected in parallel to decrease the impedance, or in series to increase the pulse length.
Plaxica Limited | Open Energy Information
OpenEI (Open Energy Information) [EERE & EIA]
Zip: SW7 2AZ Product: UK-based technology company developing a new generation of polymers derived from sustainable resources. References: Plaxica Limited1 This article is a...
Passive fault current limiting device
Evans, D.J.; Cha, Y.S.
1999-04-06
A passive current limiting device and isolator is particularly adapted for use at high power levels for limiting excessive currents in a circuit in a fault condition such as an electrical short. The current limiting device comprises a magnetic core wound with two magnetically opposed, parallel connected coils of copper, a high temperature superconductor or other electrically conducting material, and a fault element connected in series with one of the coils. Under normal operating conditions, the magnetic flux density produced by the two coils cancel each other. Under a fault condition, the fault element is triggered to cause an imbalance in the magnetic flux density between the two coils which results in an increase in the impedance in the coils. While the fault element may be a separate current limiter, switch, fuse, bimetal strip or the like, it preferably is a superconductor current limiter conducting one-half of the current load compared to the same limiter wired to carry the total current of the circuit. The major voltage during a fault condition is in the coils wound on the common core in a preferred embodiment. 6 figs.
Passive fault current limiting device
Evans, Daniel J.; Cha, Yung S.
1999-01-01
A passive current limiting device and isolator is particularly adapted for use at high power levels for limiting excessive currents in a circuit in a fault condition such as an electrical short. The current limiting device comprises a magnetic core wound with two magnetically opposed, parallel connected coils of copper, a high temperature superconductor or other electrically conducting material, and a fault element connected in series with one of the coils. Under normal operating conditions, the magnetic flux density produced by the two coils cancel each other. Under a fault condition, the fault element is triggered to cause an imbalance in the magnetic flux density between the two coils which results in an increase in the impedance in the coils. While the fault element may be a separate current limiter, switch, fuse, bimetal strip or the like, it preferably is a superconductor current limiter conducting one-half of the current load compared to the same limiter wired to carry the total current of the circuit. The major voltage during a fault condition is in the coils wound on the common core in a preferred embodiment.
Testing universal relations of neutron stars with a nonlinear matter-gravity coupling theory
Sham, Y.-H.; Lin, L.-M.; Leung, P. T. E-mail: lmlin@phy.cuhk.edu.hk
2014-02-01
Due to our ignorance of the equation of state (EOS) beyond nuclear density, there is still no unique theoretical model for neutron stars (NSs). It is therefore surprising that universal EOS-independent relations connecting different physical quantities of NSs can exist. Lau et al. found that the frequency of the f-mode oscillation, the mass, and the moment of inertia are connected by universal relations. More recently, Yagi and Yunes discovered the I-Love-Q universal relations among the mass, the moment of inertia, the Love number, and the quadrupole moment. In this paper, we study these universal relations in the Eddington-inspired Born-Infeld (EiBI) gravity. This theory differs from general relativity (GR) significantly only at high densities due to the nonlinear coupling between matter and gravity. It thus provides us an ideal case to test how robust the universal relations of NSs are with respect to the change of the gravity theory. Due to the apparent EOS formulation of EiBI gravity developed recently by Delsate and Steinhoff, we are able to study the universal relations in EiBI gravity using the same techniques as those in GR. We find that the universal relations in EiBI gravity are essentially the same as those in GR. Our work shows that, within the currently viable coupling constant, there exists at least one modified gravity theory that is indistinguishable from GR in view of the unexpected universal relations.
Two-phase reduced gravity experiments for a space reactor design
Antoniak, Z.I.
1986-08-01
Future space missions envision the use of large nuclear reactors utilizing either a single or a two-phase alkali-metal working fluid. The design and analysis of such reactors require state-of-the-art computer codes that can properly treat alkali-metal flow and heat transfer in a reduced-gravity environment. New flow regime maps, models, and correlations are required if the codes are to be successfully applied to reduced-gravity flow and heat transfer. General plans are put forth for the reduced-gravity experiments which will have to be performed, at NASA facilities, with benign fluids. Data from the reduced-gravity experiments with innocuous fluids are to be combined with normal gravity data from two-phase alkali-metal experiments. Because these reduced-gravity experiments will be very basic, and will employ small test loops of simple geometry, a large measure of commonality exists between them and experiments planned by other organizations. It is recommended that a committee be formed, to coordinate all ongoing and planned reduced gravity flow experiments.
ROHATGI,U.S.; JO,J.; CHUNG,B.D.; TAKAHASHI,H.
2002-06-09
Safety analyses of a proliferation resistant, economically competitive, high conversion, boiling water reactor (HCBWR) fueled with fissile plutonium and fertile thorium oxide fuel elements, and with passive safety systems are presented here. The HCBWR developed here is characterized by a very tight lattice with a relatively small water volume fraction in the core which therefore operates with a fast reactor neutron spectrum, and a considerably improved neutron economy compared to the current generation of Light Water Reactors. The tight lattice core has a very narrow flow channels with a hydraulic diameter less than half of the regular BWR core and, thus, presents a special challenge to core cooling, because of reduced water inventory and high friction in the core. The primary safety concern when reducing the moderator to fuel ratio and when using a tightly packed lattice arrangement is to maintain adequate cooling of the core during both normal operation and accident scenarios. In the preliminary HCBWR design, the core has been placed in a vessel with a large chimney section, and the vessel is connected with Isolation Condenser System (ICs). The vessel is placed in containment with Gravity Driven Cooling System (GDCS) and Passive Containment Cooling System (PCCS) in a configuration similar to General Electric's Simplified Boiling Water Reactor (SBWR). The safety systems are similar to SBWR; ICs and PCCS are scaled with power. An internal recirculation pump was placed in the downcomer to augment the buoyancy head provided by the chimney, since the buoyancy provided by the chimney alone could not generate sufficient recirculation in the vessel as the tight lattice configuration resulted in much larger friction in the core than the SBWR. The constitutive relationships for RELAP5 were assessed for narrow channels, and as a result the heat transfer package was modified. The modified RELAP5 was used to simulate and analyze two of the most limiting events for a tight
Upendra Rohatgi; Jae Jo; Bub Dong Chung; Hiroshi Takahashi [Brookhaven National Laboratory, Energy Sciences and Technology Department, Upton, New York 11973 (United States); Downar, T.J. [Purdue University, School of Nuclear Engineering, West Lafayette, IN 47906-1290 (United States)
2002-07-01
Safety analyses of a proliferation resistant, economically competitive, high conversion, boiling water reactor (HCBWR) fueled with fissile plutonium and fertile thorium oxide fuel elements, and with passive safety systems are presented here. The HCBWR developed here is characterized by a very tight lattice with a relatively small water volume fraction in the core which therefore operates with a fast reactor neutron spectrum, and a considerably improved neutron economy compared to the current generation of Light Water Reactors. A tight lattice BWR core has very narrow flow channels with a hydraulic diameter less than half of the regular BWR core. The tight lattice core presented a special challenge to core cooling, because of reduced water inventory and high friction in the core. The primary safety concern when reducing the moderator to fuel ratio and when using a tightly packed lattice arrangement is to maintain adequate cooling of the core during both normal operation and accident scenarios. In the preliminary HCBWR design, the core has been placed in a vessel with a large chimney section, and the vessel is connected with an Isolation Cooling System (ICS). The vessel is placed in a containment with a Gravity Driven Cooling System (GDCS) and a Passive Containment Cooling System (PCCS) in a configuration similar to General Electric's (GE) Simplified Boiling Water Reactor (SBWR). The safety systems are similar to the SBWR; the ICS and PCCS are scaled with power. An internal recirculation pump was placed in the downcomer to augment the buoyancy head provided by the chimney. The buoyancy provided by the chimney alone could not generate sufficient recirculation in the vessel since the tight lattice configuration resulted in much larger friction in the core than the SBWR. A modified RELAP5 Code was used to simulate and analyze two of the most limiting events for a tight pitch lattice core: the Station Blackout and the Main Steam Line Break events. The constitutive
Electric and magnetic field reduction by alternative transmission line options
Stewart, J.R. ); Dale, S.J. ); Klein, K.W. )
1991-01-01
Ground level electric, and more recently magnetic, fields from overhead power transmission lines are increasingly important considerations in right of way specification, with states setting or planning to set edge of right of way limits. Research has been conducted in high phase order power transmission wherein six of twelve phases are used to transmit power in less physical space and with reduced electrical environmental effects than conventional designs. The first magnetic field testing, as reported in this paper, has verified predictive methods for determination of magnetic fields from high phase order lines. Based on these analytical methods, field profiles have been determined for lines of different phase order of comparable power capacity. Potential advantages of high phase order as a means of field mitigation are discussed. 10 refs., 12 figs., 3 tabs.
getnim - NIM's Command Line Interface
U.S. Department of Energy (DOE) - all webpages (Extended Search)
getnim command getnim - NIM's Command Line Interface This page describes the inquiry-only command called getnim that users can use interactively and in scripts to get their account balances. GETNIM(l) NERSC GETNIM(l) NAME getnim - query the NERSC banking database for remaining allocation, resources and repository information SYNOPSIS getnim [ options ] -Rrname or getnim [ options ] -Rrname { -uuid | -Uuname } or getnim [ options ][ -D ] { -uuid | -Uuname } or getnim [ options ] -Rrname { -l | -L
V Fuels Biodiesel Limited | Open Energy Information
OpenEI (Open Energy Information) [EERE & EIA]
Biodiesel Limited Jump to: navigation, search Name: V-Fuels Biodiesel Limited Place: United Kingdom Product: UK-based biodiesel producers. References: V-Fuels Biodiesel Limited1...
Belize Electricity Limited | Open Energy Information
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Belize Electricity Limited Jump to: navigation, search Logo: Belize Electricity Limited Name: Belize Electricity Limited Abbreviation: BEL Address: PO Box 327 Place: Belize City,...
Pento, Robert; Marks, James E.; Staffanson, Clifford D.
1998-07-28
A thermoelectric module with a plurality of electricity generating units each having a first end and a second end, the units being arranged first end to second end along an-in-line axis. Each unit includes first and second elements each made of a thermoelectric material, an electrically conductive hot member arranged to heat one side of the first element, and an electrically conductive cold member arranged to cool another side of the first element and to cool one side of the second element. The hot member, the first element, the cold member and the second element are supported in a fixture, are electrically connected respectively to provide an electricity generating unit, and are arranged respectively in positions along the in-line axis. The individual components of each generating unit and the respective generating units are clamped in their in-line positions by a loading bolt at one end of the fixture and a stop wall at the other end of the fixture. The hot members may have a T-shape and the cold members an hourglass shape to facilitate heat transfer. The direction of heat transfer through the hot members may be perpendicular to the direction of heat transfer through the cold members, and both of these heat transfer directions maybe perpendicular to the direction-of current flow through the module.
Pento, Robert; Marks, James E.; Staffanson, Clifford D.
2000-01-01
A thermoelectric module with a plurality of electricity generating units each having a first end and a second end, the units being arranged first end to second end along an in-line axis. Each unit includes first and second elements each made of a thermoelectric material, an electrically conductive hot member arranged to heat one side of the first element, and an electrically conductive cold member arranged to cool another side of the first element and to cool one side of the second element. The hot member, the first element, the cold member and the second element are supported in a fixture, are electrically connected respectively to provide an electricity generating unit, and are arranged respectively in positions along the in-line axis. The individual components of each generating unit and the respective generating units are clamped in their in-line positions by a loading bolt at one end of the fixture and a stop wall at the other end of the fixture. The hot members may have a T-shape and the cold members an hourglass shape to facilitate heat transfer. The direction of heat transfer through the hot members may be perpendicular to the direction of heat transfer through the cold members, and both of these heat transfer directions may be perpendicular to the direction of current flow through the module.
Tsujimoto, K.; Fujii, K.; Kubokawa, H.; Okomura, T.; Simojima, K.; Yoshioka, V.
1982-11-01
In Japan it has recently become necessary to shorten the interphase spacing in overhead transmission lines because of land limitations and economical considerations. In this connection, the authors have attempted to analyze, in-depth, the possibilities of shortened interphase spacing via conductor swinging caused by wind effects: one of the important factors in the design of more compact overhead lines. This paper describes not only the investigative results of conductor swinging that were obtained both through computer simulation and in 3 years of full scale field line testing, but also design methodology for compact overhead lines based on these results.
Quantum-gravity induced Lorentz violation and dynamical mass generation
Mavromatos, Nick E.
2011-01-15
In the eprint by Jean Alexandre [arXiv:1009.5834], a minimal extension of (3+1)-dimensional quantum electrodynamics has been proposed, which includes Lorentz violation (LV) in the form of higher-(spatial)-derivative isotropic terms in the gauge sector, suppressed by a mass scale M. The model can lead to dynamical mass generation for charged fermions. In this article, I elaborate further on this idea and I attempt to connect it to specific quantum-gravity models, inspired from string/brane theory. Specifically, in the first part of the article, I comment briefly on the gauge dependence of the dynamical mass generation in the approximations of J. Alexandre [arXiv:1009.5834.], and I propose a possible avenue for obtaining the true gauge-parameter-independent value of the mass by means of pinch technique argumentations. In the second part of the work, I embed the LV QED model into multibrane world scenarios with a view to provide a geometrical way of enhancing the dynamical mass to phenomenologically realistic values by means of bulk warp metric factors, in an (inverse) Randall-Sundrum hierarchy. Finally, in the third part of this paper, I demonstrate that such Lorentz-violating QED models may represent parts of a low-energy effective action (of Finsler-Born-Infeld type) of open strings propagating in quantum D0-particle stochastic space-time foam backgrounds, which are viewed as consistent quantum-gravity configurations. To capture correctly the quantum-fluctuating nature of the foam background, I replace the D0-recoil-velocity parts of this action by appropriate gradient operators in three-space, keeping the photon field part intact. This is consistent with the summation over world-sheet genera in the first-quantized string approach. I identify a class of quantum orderings which leads to the LV QED action of J. Alexandre, arXiv:1009.5834. In this way I argue, following the logic in that work, that the D-foam can lead to dynamically generated masses for charged
Ground Gravity Survey At Cove Fort Area (Warpinski, Et Al., 2004...
OpenEI (Open Energy Information) [EERE & EIA]
Ground Gravity Survey Activity Date Usefulness not indicated DOE-funding Unknown Notes Update to Warpinski, et al., 2002 References N. R. Warpinski, A. R. Sattler, R. Fortuna, D....
Table 23. Domestic Crude Oil First Purchase Prices by API Gravity
Energy Information Administration (EIA) (indexed site)
18.62 19.26 Source: Energy Information Administration, Form EIA-182, "Domestic Crude Oil First Purchase Report." 23. Domestic Crude Oil First Purchase Prices by API Gravity Energy...
Table 23. Domestic Crude Oil First Purchase Prices by API Gravity
Energy Information Administration (EIA) (indexed site)
20.23 20.91 Source: Energy Information Administration, Form EIA-182, "Domestic Crude Oil First Purchase Report." 23. Domestic Crude Oil First Purchase Prices by API Gravity Energy...
Gravity survey of Dixie Valley, west-central Nevada | Open Energy...
OpenEI (Open Energy Information) [EERE & EIA]
to library Report: Gravity survey of Dixie Valley, west-central Nevada Author Donald H. Schaefer Published US Geological Survey, 1983 Report Number 82-111 DOI Not Provided...
Generalised BRST symmetry and gaugeon formalism for perturbative quantum gravity: Novel observation
Upadhyay, Sudhaker
2014-05-15
In this paper the novel features of Yokoyama gaugeon formalism are stressed out for the theory of perturbative quantum gravity in the Einstein curved spacetime. The quantum gauge transformations for the theory of perturbative gravity are demonstrated in the framework of gaugeon formalism. These quantum gauge transformations lead to renormalised gauge parameter. Further, we analyse the BRST symmetric gaugeon formalism which embeds more acceptable Kugo–Ojima subsidiary condition. Further, the BRST symmetry is made finite and field-dependent. Remarkably, the Jacobian of path integral under finite and field-dependent BRST symmetry amounts to the exact gaugeon action in the effective theory of perturbative quantum gravity. -- Highlights: •We analyse the perturbative gravity in gaugeon formalism. •The generalisation of BRST transformation is also studied in this context. •Within the generalised BRST framework we found the exact gaugeon modes in the theory.
Toward the AdS/CFT gravity dual for high energy collisions. II...
Office of Scientific and Technical Information (OSTI)
II. The stress tensor on the boundary Citation Details In-Document Search Title: Toward the AdSCFT gravity dual for high energy collisions. II. The stress tensor on the boundary ...
Violation of the first law of black hole thermodynamics in f(T) gravity
Miao, Rong-Xin; Li, Miao; Miao, Yan-Gang E-mail: mli@itp.ac.cn
2011-11-01
We prove that, in general, the first law of black hole thermodynamics, ?Q = T?S, is violated in f(T) gravity. As a result, it is possible that there exists entropy production, which implies that the black hole thermodynamics can be in non-equilibrium even in the static spacetime. This feature is very different from that of f(R) or that of other higher derivative gravity theories. We find that the violation of first law results from the lack of local Lorentz invariance in f(T) gravity. By investigating two examples, we note that f''(0) should be negative in order to avoid the naked singularities and superluminal motion of light. When f''(T) is small, the entropy of black holes in f(T) gravity is approximatively equal to f'(T)/4 A.
Mirzatuny, Nareg; Khosravi, Shahram; Baghram, Shant; Moshafi, Hossein E-mail: khosravi@mail.ipm.ir E-mail: hosseinmoshafi@iasbs.ac.ir
2014-01-01
In this work we study the simultaneous effect of primordial non-Gaussianity and the modification of the gravity in f(R) framework on large scale structure observations. We show that non-Gaussianity and modified gravity introduce a scale dependent bias and growth rate functions. The deviation from Î›CDM in the case of primordial non-Gaussian models is in large scales, while the growth rate deviates from Î›CDM in small scales for modified gravity theories. We show that the redshift space distortion can be used to distinguish positive and negative f{sub NL} in standard background, while in f(R) theories they are not easily distinguishable. The galaxy power spectrum is generally enhanced in presence of non-Gaussianity and modified gravity. We also obtain the scale dependence of this enhancement. Finally we define galaxy growth rate and galaxy growth rate bias as new observational parameters to constrain cosmology.
Axi-dilaton gravity in D{>=}4 dimensional space-times with torsion
Cebeci, H.; Dereli, T.
2005-01-15
We study models of axi-dilaton gravity in space-time geometries with torsion. We discuss conformal rescaling rules in both Riemannian and non-Riemannian formulations. We give static, spherically symmetric solutions and examine their singularity behavior.
New Cosmologies on the Horizon. Cosmology and Holography in bigravity and massive gravity
Tolley, Andrew James
2013-03-31
The goal of this research program is to explore the cosmological dynamics, the nature of cosmological and black hole horizons, and the role of holography in a new class of infrared modified theories of gravity. This will capitalize of the considerable recent progress in our understanding of the dynamics of massive spin two fields on curved spacetimes, culminating in the formulation of the first fully consistent theories of massive gravity and bigravity/bimetric theories.
Uniform density static fluid sphere in Einstein-Gauss-Bonnet gravity and its universality
Dadhich, Naresh; Molina, Alfred; Khugaev, Avas
2010-05-15
In Newtonian theory, gravity inside a constant density static sphere is independent of spacetime dimension. Interestingly this general result is also carried over to Einsteinian as well as higher order Einstein-Gauss-Bonnet (Lovelock) gravity notwithstanding their nonlinearity. We prove that the necessary and sufficient condition for universality of the Schwarzschild interior solution describing a uniform density sphere for all n{>=}4 is that its density is constant.
Modification to the luminosity distance redshift relation in modified gravity theories
Flanagan, Eanna E.; Rosenthal, Eran; Wasserman, Ira M.
2009-02-15
We derive an expression for the luminosity distance as a function of redshift for a flat Robertson-Walker spacetime perturbed by arbitrary scalar perturbations possibly produced by a modified gravity theory with two different scalar perturbation potentials. Measurements of the luminosity distance as function of redshift provide a constraint on a combination of the scalar potentials and so they can complement weak lensing and other measurements in trying to distinguish among the various alternative theories of gravity.
Observation of gravity decays of multiple-neutron nuclei during cold fusion
Matsumoto, T. . Dept. of Nuclear Engineering)
1992-08-01
The Nattoh model predicted that multiple-neutron nuclei such as quad-neutrons can be produced during cold fusion, and the gravity decays of the quad-neutrons were recorded on nuclear emulsions. Several different traces that might be produced by the gravity decays of di-neutron and multiple-neutron nuclei have been successfully observed. The mechanisms of the production of multiple-neutron nuclei are discussed in this paper.
Borehole Gravity Meter Surveys at the Waste Treatment Plant, Hanford, Washington.
MacQueen, Jeffrey D.; Mann, Ethan
2007-04-06
Microg-LaCoste (MGL) was contracted by Pacfic Northwest National Laboratories (PNNL) to record borehole gravity density data in 3 wells at the HanfordWaste Treatment Plant (WTP) site. The survey was designed to provide highly accurate density information for use in seismic modeling. The borehole gravity meter (BHGM) tool has a very large depth of investigation (hundreds of feet) compared to other density tools so it is not influenced by casing or near welbore effects, such as washouts.
General results for higher spin Wilson lines and entanglement in Vasiliev theory
Hegde, Ashwin; Kraus, Per; Perlmutter, Eric
2016-01-28
Here, we develop tools for the efficient evaluation of Wilson lines in 3D higher spin gravity, and use these to compute entanglement entropy in the hs[Î» ] Vasiliev theory that governs the bulk side of the duality proposal of Gaberdiel and Gopakumar. Our main technical advance is the determination of SL(N) Wilson lines for arbitrary N, which, in suitable cases, enables us to analytically continue to hs[Î» ] via Nâ†’ -Î». We then apply this result to compute various quantities of interest, including entanglement entropy expanded perturbatively in the background higher spin charge, chemical potential, and interval size. This includesmoreÂ Â» a computation of entanglement entropy in the higher spin black hole of the Vasiliev theory. Our results are consistent with conformal field theory calculations. We also provide an alternative derivation of the Wilson line, by showing how it arises naturally from earlier work on scalar correlators in higher spin theory. The general picture that emerges is consistent with the statement that the SL(N) Wilson line computes the semiclassical WN vacuum block, and our results provide an explicit result for this object.Â«Â less
Generalized second law of thermodynamics in f(T) gravity
Karami, K.; Abdolmaleki, A. E-mail: AAbdolmaleki@uok.ac.ir
2012-04-01
We investigate the validity of the generalized second law (GSL) of gravitational thermodynamics in the framework of f(T) modified teleparallel gravity. We consider a spatially flat FRW universe containing only the pressureless matter. The boundary of the universe is assumed to be enclosed by the Hubble horizon. For two viable f(T) models containing f(T) = T+?{sub 1}((?T)){sup n} and f(T) = T??{sub 2}T(1?e{sup ?T{sub 0}/T}), we first calculate the effective equation of state and deceleration parameters. Then, (we investigate the null and strong energy conditions and conclude that a sudden future singularity appears in both models. Furthermore, using a cosmographic analysis we check the viability of two models. Finally, we examine the validity of the GSL and find that for both models it) is satisfied from the early times to the present epoch. But in the future, the GSL is violated for the special ranges of the torsion scalar T.
Topological black holes in Lovelock-Born-Infeld gravity
Dehghani, M. H.; Alinejadi, N.; Hendi, S. H.
2008-05-15
In this paper, we present topological black holes of third order Lovelock gravity in the presence of cosmological constant and nonlinear electromagnetic Born-Infeld field. Depending on the metric parameters, these solutions may be interpreted as black hole solutions with inner and outer event horizons, an extreme black hole or naked singularity. We investigate the thermodynamics of asymptotically flat solutions and show that the thermodynamic and conserved quantities of these black holes satisfy the first law of thermodynamic. We also endow the Ricci flat solutions with a global rotation and calculate the finite action and conserved quantities of these class of solutions by using the counterterm method. We compute the entropy through the use of the Gibbs-Duhem relation and find that the entropy obeys the area law. We obtain a Smarr-type formula for the mass as a function of the entropy, the angular momenta, and the charge, and compute temperature, angular velocities, and electric potential and show that these thermodynamic quantities coincide with their values which are computed through the use of geometry. Finally, we perform a stability analysis for this class of solutions in both the canonical and the grand-canonical ensemble and show that the presence of a nonlinear electromagnetic field and higher curvature terms has no effect on the stability of the black branes, and they are stable in the whole phase space.
Avoidance of singularities in asymptotically safe Quantum Einstein Gravity
Kofinas, Georgios; Zarikas, Vasilios
2015-10-30
New general spherically symmetric solutions have been derived with a cosmological â€śconstantâ€ť Î› as a source. This Î› term is not constant but it satisfies the properties of the asymptotically safe gravity at the ultraviolet fixed point. The importance of these solutions comes from the fact that they may describe the near to the centre region of black hole spacetimes as this is modified by the Renormalization Group scaling behaviour of the fields. The consistent set of field equations which respect the Bianchi identities is derived and solved. One of the solutions (with conventional sign of temporal-radial metric components) is timelike geodesically complete, and although there is still a curvature divergent origin, this is never approachable by an infalling massive particle which is reflected at a finite distance due to the repulsive origin. Another family of solutions (of both signatures) range from a finite radius outwards, they cannot be extended to the centre of spherical symmetry, and the curvature invariants are finite at the minimum radius.
Slowly rotating neutron and strange stars in R{sup 2} gravity
Staykov, Kalin V.; Yazadjiev, Stoytcho S.; Doneva, Daniela D.; Kokkotas, Kostas D. E-mail: daniela.doneva@uni-tuebingen.de E-mail: kostas.kokkotas@uni-tuebingen.de
2014-10-01
In the present paper we investigate self-consistently slowly rotating neutron and strange stars in R-squared gravity with Lagrangian f(R) = R + aR{sup 2}, where a is a parameter. For this purpose we first derive the equations describing the structure of the slowly rotating compact stars in f(R)-gravity and then simultaneously solve numerically the exterior and the interior problem. The structure of the slowly rotating neutron stars is studied for two different hadronic equations of state and a strange matter equation of state. The moment of inertia and its dependence on the stellar mass and the R-squared gravity parameter a is also examined in details. The numerical results show that the neutron star moment of inertia can be up to 30% larger compared to the corresponding general relativistic models. This is much higher than the change in the maximum mass induced by R-squared gravity and is beyond the EOS uncertainty. In this way the future observations of the moment of inertia of compact stars could allow us to distinguish between general relativity and f(R) gravity, and more generally to test the strong field regime of gravity.
AN EXTREME GRAVITATIONALLY REDSHIFTED IRON LINE AT 4.8 KeV IN Mrk 876
Bottacini, Eugenio; Orlando, Elena; Moskalenko, Igor [W. W. Hansen Experimental Physics Laboratory and Kavli Institute for Particle Astrophysics and Cosmology, Stanford University (United States); Greiner, Jochen [Max-Planck-Institut für extraterrestrische Physik, Giessenbachstrasse 1, D-85748 Garching (Germany); Ajello, Marco [Department of Physics and Astronomy, Clemson University, Clemson, SC 29634-0978 (United States); Persic, Massimo, E-mail: eugenio.bottacini@stanford.edu [INAF-Trieste, via G.B.Tiepolo 11, I-34143 Trieste (Italy)
2015-01-01
X-ray spectral lines at unforeseen energies are important because they can shed light on the extreme physical conditions of the environment around the supermassive black holes of active galactic nuclei (AGNs). Mrk 876 displays such a line at 4.80{sub ?0.04}{sup +0.05} rest-frame energy. A possible interpretation of its origin can be found in the hotspot scenario. In this scenario, the primary radiation from a flare in the hot corona of an AGN illuminates a limited portion of the accretion disk that emits by fluorescence. In this context, the line can represent an extreme gravitationally redshifted Fe line originating on the accretion disk below six gravitational radii from a rotating supermassive black hole. The correct estimate of the line significance requires a dedicated approach. Based on an existing rigorous approach, we have performed extensive Monte Carlo simulations. We determine that the line is a real feature at a ?99% confidence level.
Thermal island destabilization and the Greenwald limit
White, R. B.; Gates, D. A.; Brennan, D. P.
2015-02-24
Magnetic reconnection is ubiquitous in the magnetosphere, the solar corona, and in toroidal fusion research discharges. A magnetic island saturates at a width which produces a minimum in the magnetic energy of the configuration is evident in a fusion device. At saturation, the modified current density profile, a function of the flux in the island, is essentially flat, the growth rate proportional to the difference in the current at the O-point and the X-point. Furthermore, modification of the current density profile in the island interior causes a change in the island stability and additional growth or contraction of the saturatedmoreÂ Â» island. Because field lines in an island are isolated from the outside plasma, an island can heat or cool preferentially depending on the balance of Ohmic heating and radiation loss in the interior, changing the resistivity and hence the current in the island. A simple model of island destabilization due to radiation cooling of the island is constructed, and the effect of modification of the current within an island is calculated. In addition destabilization effect is described, and it is shown that a small imbalance of heating can lead to exponential growth of the island. A destabilized magnetic island near the plasma edge can lead to plasma loss, and because the radiation is proportional to plasma density and charge, this effect can cause an impurity dependent density limit.Â«Â less
Thermal island destabilization and the Greenwald limit
White, R. B.; Gates, D. A.; Brennan, D. P.
2015-02-15
Magnetic reconnection is ubiquitous in the magnetosphere, the solar corona, and in toroidal fusion research discharges. In a fusion device, a magnetic island saturates at a width which produces a minimum in the magnetic energy of the configuration. At saturation, the modified current density profile, a function of the flux in the island, is essentially flat, the growth rate proportional to the difference in the current at the O-point and the X-point. Further modification of the current density profile in the island interior causes a change in the island stability and additional growth or contraction of the saturated island. Because field lines in an island are isolated from the outside plasma, an island can heat or cool preferentially depending on the balance of Ohmic heating and radiation loss in the interior, changing the resistivity and hence the current in the island. A simple model of island destabilization due to radiation cooling of the island is constructed, and the effect of modification of the current within an island is calculated. An additional destabilization effect is described, and it is shown that a small imbalance of heating can lead to exponential growth of the island. A destabilized magnetic island near the plasma edge can lead to plasma loss, and because the radiation is proportional to plasma density and charge, this effect can cause an impurity dependent density limit.
Tritium Detection Methods and Limitations
Office of Environmental Management (EM)
Detection Methods and Limitations Tritium Focus Group Meeting, April 2014 Tom Voss, Northern New Mexico DOE-HDBK-1105-2002 RADIOLOGICAL TRAINING FOR TRITIUM FACILITIES U.S. Department of Energy AREA TRNG Washington, D.C. 20585 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. DOE-HDBK-1105-2002 Radiological Training for Tritium Facilities U.S. Department of Energy, Radiological Control Programs for Special Tritium Compounds, DOE-STD- draft, Washington, D.C.
Summary of Dissolved Concentration Limits
Yueting Chen
2001-06-11
According to the Technical Work Plan titled Technical Work Plan for Waste Form Degradation Process Model Report for SR (CRWMS M&O 2000a), the purpose of this study is to perform abstractions on solubility limits of radioactive elements based on the process-level information and thermodynamic databases provided by Natural Environment Program Operations (NEPO) and Waste Package Operations (WPO). The scope of this analysis is to produce solubility limits as functions, distributions, or constants for all transported radioactive elements identified by the Performance Assessment Operations (PAO) radioisotope screening. Results from an expert elicitation for solubility limits of most radioactive elements were used in the previous Total System Performance Assessments (TSPAs). However, the elicitation conducted in 1993 does not meet the criteria set forth by the U.S. Nuclear Regulatory Commission (NRC) due to lack of documentation and traceability (Kotra et al. 1996, Section 3). Therefore, at the Waste Form Abstraction Workshop held on February 2-4, 1999, at Albuquerque, New Mexico, the Yucca Mountain Site Characterization Project (YMP) decided to develop geochemical models to study solubility for the proposed Monitored Geologic Repository. WPO/NEPO is to develop process-level solubility models, including review and compilation of relevant thermodynamic data. PAO's responsibility is to perform abstractions based on the process models and chemical conditions and to produce solubility distributions or response surfaces applicable to the proposed repository. The results of this analysis and conceptual model will feed the performance assessment for Total System Performance Assessment--Site Recommendation (TSPA-SR) and Total System Performance Assessment--License Application (TSPA-LA), and to the Waste Form Degradation Process Model Report section on concentration limits.
Lumped transmission line avalanche pulser
Booth, R.
1995-07-18
A lumped linear avalanche transistor pulse generator utilizes stacked transistors in parallel within a stage and couples a plurality of said stages, in series with increasing zener diode limited voltages per stage and decreasing balanced capacitance load per stage to yield a high voltage, high and constant current, very short pulse. 8 figs.
Lumped transmission line avalanche pulser
Booth, Rex
1995-01-01
A lumped linear avalanche transistor pulse generator utilizes stacked transistors in parallel within a stage and couples a plurality of said stages, in series with increasing zener diode limited voltages per stage and decreasing balanced capacitance load per stage to yield a high voltage, high and constant current, very short pulse.
Plains and Eastern Clean Line Transmission Line: Comment from Save The
Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)
Ozarks | Department of Energy from Save The Ozarks Plains and Eastern Clean Line Transmission Line: Comment from Save The Ozarks Comment submitted on updated Part 2 application. Comment by Save the Ozarks 07-13-15.pdf (112.79 KB) More Documents & Publications Plains & Eastern Clean Line Transmission Line - Part 2 Application Plains & Eastern Clean Line Project Proposal for New or Upgraded Transmission Line Projects Under Section 1222 of the Energy Policy Act of 2005 Plains and
CXD 4601, Line Yard Fence Project (4601)
U.S. Department of Energy (DOE) - all webpages (Extended Search)
Line Yard Fence Project (4601) Y-12 Site Office Oak Ridge, Anderson County, Tennessee The proposed action is to install fencing around the Old Line Yard to provide protected...
FB Line Basis for Interim Operation
Shedrow, B.
1998-10-19
The safety analysis of the FB-Line Facility indicates that the operation of FB-Line to support the current mission does not present undue risk to the facility and co-located workers, general public, or the environment.
Thermodynamics of Taub-NUT/bolt black holes in Einstein-Maxwell gravity
Dehghani, M.H.; Khodam-Mohammadi, A.
2006-06-15
First, we construct the Taub-NUT/bolt solutions of (2k+2)-dimensional Einstein-Maxwell gravity, when all the factor spaces of 2k-dimensional base space B have positive curvature. These solutions depend on two extra parameters, other than the mass and the NUT charge. These are electric charge q and electric potential at infinity V. We investigate the existence of Taub-NUT solutions and find that in addition to the two conditions of uncharged NUT solutions, there exist two extra conditions. These two extra conditions come from the regularity of vector potential at r=N and the fact that the horizon at r=N should be the outer horizon of the NUT charged black hole. We find that the NUT solutions in 2k+2 dimensions have no curvature singularity at r=N, when the 2k-dimensional base space is chosen to be CP{sup 2k}. For bolt solutions, there exists an upper limit for the NUT parameter which decreases as the potential parameter increases. Second, we study the thermodynamics of these spacetimes. We compute temperature, entropy, charge, electric potential, action and mass of the black hole solutions, and find that these quantities satisfy the first law of thermodynamics. We perform a stability analysis by computing the heat capacity, and show that the NUT solutions are not thermally stable for even k's, while there exists a stable phase for odd k's, which becomes increasingly narrow with increasing dimensionality and wide with increasing V. We also study the phase behavior of the 4 and 6 dimensional bolt solutions in canonical ensemble and find that these solutions have a stable phase, which becomes smaller as V increases.
O.A.R. 734-055 - Pole Lines, Buried Cables, Pipe lines, Signs...
OpenEI (Open Energy Information) [EERE & EIA]
rules outline the requirements for location, installation, construction, maintenance and use of pole lines, buried cables, pipe lines, signs miscellaneous operations...
Jankowiak, R.J.; Small, G.J.; Shields, P.A.
1999-04-27
Capillary electrophoresis (CE) is interfaced with low temperature fluorescence line-narrowing (FLN) spectroscopy for on-line structural characterization of separated molecular analytes. 21 figs.
Jankowiak, Ryszard J.; Small, Gerald J.; Shields, Peter A.
1999-04-27
Capillary electrophoresis (CE) is interfaced with low temperature fluorescence line-narrowing (FLN) spectroscopy for on-line structural characterization of separated molecular analytes.
Gravity waves from non-minimal quadratic inflation
Pallis, Constantinos; Shafi, Qaisar
2015-03-12
We discuss non-minimal quadratic inflation in supersymmetric (SUSY) and non-SUSY models which entails a linear coupling of the inflaton to gravity. Imposing a lower bound on the parameter c{sub R}, involved in the coupling between the inflaton and the Ricci scalar curvature, inflation can be attained even for subplanckian values of the inflaton while the corresponding effective theory respects the perturbative unitarity up to the Planck scale. Working in the non-SUSY context we also consider radiative corrections to the inflationary potential due to a possible coupling of the inflaton to bosons or fermions. We find ranges of the parameters, depending mildly on the renormalization scale, with adjustable values of the spectral index n{sub s}, tensor-to-scalar ratio râ‰(2â’4)â‹…10{sup â’3}, and an inflaton mass close to 3â‹…10{sup 13} GeV. In the SUSY framework we employ two gauge singlet chiral superfields, a logarithmic KĂ¤hler potential including all the allowed terms up to fourth order in powers of the various fields, and determine uniquely the superpotential by applying a continuous R and a global U(1) symmetry. When the KĂ¤hler manifold exhibits a no-scale-type symmetry, the model predicts n{sub s}â‰0.963 and râ‰0.004. Beyond no-scale SUGRA, n{sub s} and r depend crucially on the coefficient involved in the fourth order term, which mixes the inflaton with the accompanying non-inflaton field in the KĂ¤hler potential, and the prefactor encountered in it. Increasing slightly the latter above (â’3), an efficient enhancement of the resulting r can be achieved putting it in the observable range. The inflaton mass in the last case is confined in the range (5â’9)â‹…10{sup 13} GeV.
Effective field theory of gravity for extended objects
Goldberger, Walter D.; Rothstein, Ira Z.
2006-05-15
Using effective field theory (EFT) methods we present a Lagrangian formalism which describes the dynamics of nonrelativistic extended objects coupled to gravity. The formalism is relevant to understanding the gravitational radiation power spectra emitted by binary star systems, an important class of candidate signals for gravitational wave observatories such as LIGO or VIRGO. The EFT allows for a clean separation of the three relevant scales: r{sub s}, the size of the compact objects, r, the orbital radius, and r/v, the wavelength of the physical radiation (where the velocity v is the expansion parameter). In the EFT, radiation is systematically included in the v expansion without the need to separate integrals into near zones and radiation zones. Using the EFT, we show that the renormalization of ultraviolet divergences which arise at v{sup 6} in post-Newtonian (PN) calculations requires the presence of two nonminimal worldline gravitational couplings linear in the Ricci curvature. However, these operators can be removed by a redefinition of the metric tensor, so that the divergences arising at v{sup 6} have no physically observable effect. Because in the EFT finite size features are encoded in the coefficients of nonminimal couplings, this implies a simple proof of the decoupling of internal structure for spinless objects to at least order v{sup 6}. Neglecting absorptive effects, we find that the power counting rules of the EFT indicate that the next set of short distance operators, which are quadratic in the curvature and are associated with tidal deformations, does not play a role until order v{sup 10}. These operators, which encapsulate finite size properties of the sources, have coefficients that can be fixed by a matching calculation. By including the most general set of such operators, the EFT allows one to work within a point-particle theory to arbitrary orders in v.
Magnetically insulated transmission line oscillator
Bacon, Larry D.; Ballard, William P.; Clark, M. Collins; Marder, Barry M.
1988-01-01
A magnetically insulated transmission line oscillator employs self-generated magnetic fields to generate microwave energy. An anode of the oscillator includes slow-wave structures which are formed of a plurality of thin conductive vanes defining cavities therebetween, and a gap is formed between the anode and a cathode of the oscillator. In response to a pulsed voltage applied to the anode and cathode, self-generated magnetic fields arfe produced in a cross-field orientation with respect to the orientation of the electric field between the anode and the cathode. The cross-field magnetic fields insulate the flow of electrons in the gap and confine the flow of electrons within the gap.
Magnetically insulated transmission line oscillator
Bacon, L.D.; Ballard, W.P.; Clark, M.C.; Marder, B.M.
1987-05-19
A magnetically insulated transmission line oscillator employs self-generated magnetic fields to generate microwave energy. An anode of the oscillator includes slow-wave structures which are formed of a plurality of thin conductive vanes defining cavities therebetween, and a gap is formed between the anode and a cathode of the oscillator. In response to a pulsed voltage applied to the anode and cathode, self-generated magnetic fields are produced in a cross-field orientation with respect to the orientation of the electric field between the anode and the cathode. The cross-field magnetic fields insulate the flow of electrons in the gap and confine the flow of electrons within the gap. 11 figs.
Superconducting transmission line particle detector
Gray, K.E.
1988-07-28
A microvertex particle detector for use in a high energy physic collider including a plurality of parallel superconducting thin film strips separated from a superconducting ground plane by an insulating layer to form a plurality of superconducting waveguides. The microvertex particle detector indicates passage of a charged subatomic particle by measuring a voltage pulse measured across a superconducting waveguide caused by the transition of the superconducting thin film strip from a superconducting to a non- superconducting state in response to the passage of a charged particle. A plurality of superconducting thin film strips in two orthogonal planes plus the slow electromagnetic wave propagating in a superconducting transmission line are used to resolve N/sup 2/ ambiguity of charged particle events. 6 figs.
Superconducting transmission line particle detector
Gray, Kenneth E.
1989-01-01
A microvertex particle detector for use in a high energy physic collider including a plurality of parallel superconducting thin film strips separated from a superconducting ground plane by an insulating layer to form a plurality of superconducting waveguides. The microvertex particle detector indicates passage of a charged subatomic particle by measuring a voltage pulse measured across a superconducting waveguide caused by the transition of the superconducting thin film strip from a superconducting to a non-superconducting state in response to the passage of a charged particle. A plurality of superconducting thin film strips in two orthogonal planes plus the slow electromagnetic wave propogating in a superconducting transmission line are used to resolve N.sup.2 ambiguity of charged particle events.
Unsplit bipolar pulse forming line
Rhodes, Mark A.
2011-05-24
A bipolar pulse forming transmission line module and system for linear induction accelerators having first, second, third, and fourth planar conductors which form a sequentially arranged interleaved stack having opposing first and second ends, with dielectric layers between the conductors. The first and second planar conductors are connected to each other at the first end, and the first and fourth planar conductors are connected to each other at the second end via a shorting plate. The third planar conductor is electrically connectable to a high voltage source, and an internal switch functions to short at the first end a high voltage from the third planar conductor to the fourth planar conductor to produce a bipolar pulse at the acceleration axis with a zero net time integral. Improved access to the switch is enabled by an aperture through the shorting plate and the proximity of the aperture to the switch.
A Sea Floor Gravity Survey of the Sleipner Field to Monitor CO2 Migration
Mark Zumberge
2011-09-30
Carbon dioxide gas (CO{sub 2}) is a byproduct of many wells that produce natural gas. Frequently the CO{sub 2} separated from the valuable fossil fuel gas is released into the atmosphere. This adds to the growing problem of the climatic consequences of greenhouse gas contamination. In the Sleipner North Sea natural gas production facility, the separated CO{sub 2} is injected into an underground saline aquifer to be forever sequestered. Monitoring the fate of such sequestered material is important - and difficult. Local change in Earth's gravity field over the injected gas is one way to detect the CO{sub 2} and track its migration within the reservoir over time. The density of the injected gas is less than that of the brine that becomes displaced from the pore space of the formation, leading to slight but detectable decrease in gravity observed on the seafloor above the reservoir. Using equipment developed at Scripps Institution of Oceanography, we have been monitoring gravity over the Sleipner CO{sub 2} sequestration reservoir since 2002. We surveyed the field in 2009 in a project jointly funded by a consortium of European oil and gas companies and the US Department of Energy. The value of gravity at some 30 benchmarks on the seafloor, emplaced at the beginning of the monitoring project, was observed in a week-long survey with a remotely operated vehicle. Three gravity meters were deployed on the benchmarks multiple times in a campaign-style survey, and the measured gravity values compared to those collected in earlier surveys. A clear signature in the map of gravity differences is well correlated with repeated seismic surveys.
Aad, G.; Abbott, B.; Abdallah, J.; Abdinov, O.; Abeloos, B.; Aben, R.; Abolins, M.; AbouZeid, O. S.; Abramowicz, H.; Abreu, H.; et al
2016-03-07
A search is conducted for new physics in multijet final states using 3.6 inverse femtobarns of data from proton-proton collisions at âšs = 13 TeV taken at the CERN Large Hadron Collider with the ATLAS detector. Events are selected containing at least three jets with scalar sum of jet transverse momenta (HT) greater than 1 TeV. No excess is seen at large HT and limits are presented on new physics: models which produce final states containing at least three jets and having cross sections larger than 1.6 fb with HT > 5.8 TeV are excluded. As a result, limits aremoreÂ Â» also given in terms of new physics models of strong gravity that hypothesize additional space-time dimensions.Â«Â less
Device for detecting the specific gravity of a liquid. [Patent application
Derouin, C.R.; Kerwin, W.J.; McCormick, J.B.; Bobbett, R.E.
1980-11-18
A device for detecting the specific gravity of a liquid and a device for detecting the state of charge of a liquid phase electrolyte battery are described. In one embodiment of the present invention, a change in the critical angle of total internal reflection is utilized to determine the index of refraction of the liquid to be measured. It is shown that the index of refraction of the liquid is a function of the specific gravity of the liquid. In applications for measuring the state of charge of a battery, the specific gravity is proportional to the state of charge of the battery. A change in intensity of rays intersecting an interface surface indicates the critical angle which is a direct indication of the specific gravity of the liquid and the state of charge of a battery. In another embodiment, a light beam is projected through a transparent medium and then through a portion of the liquid to be measured. A change in refraction due to a change in the index of refraction of the liquid produces a deflection of the beam which is measured by a detector. The magnitude of deflection of the beam is directly proportional to the specific gravity of the liquid and the state of charge of a battery.
Constraining the range of Yukawa gravity interaction from S2 star orbits
Borka, D.; Jovanovi?, V. Borka; Jovanovi?, P.; Zakharov, A.F. E-mail: pjovanovic@aob.rs E-mail: zakharov@itep.ru
2013-11-01
We consider possible signatures for Yukawa gravity within the Galactic Central Parsec, based on our analysis of the S2 star orbital precession around the massive compact dark object at the Galactic Centre, and on the comparisons between the simulated orbits in Yukawa gravity and two independent sets of observations. Our simulations resulted in strong constraints on the range of Yukawa interaction ? and showed that its most probable value in the case of S2 star is around 5000 - 7000 AU. At the same time, we were not able to obtain reliable constrains on the universal constant ? of Yukawa gravity, because the current observations of S2 star indicated that it may be highly correlated with parameter ? in the range (0 < ? < 1). For ? > 2 they are not correlated. However, the same universal constant which was successfully applied to clusters of galaxies and rotation curves of spiral galaxies (? = 1/3) also gives a satisfactory agreement with the observed orbital precession of the S2 star, and in that case the most probable value for the scale parameter is ? ? 3000±1500 AU. Also, the Yukawa gravity potential induces precession of S2 star orbit in the same direction as General Relativity for ? > 0 and for ? < ?1, and in the opposite direction for ?1 < ? < 0. The future observations with advanced facilities, such as GRAVITY or/and European Extremely Large Telescope, are needed in order to verify these claims.
Penarrubia, Jorge; Walker, Matthew G.
2012-11-20
We introduce the Minimum Entropy Method, a simple statistical technique for constraining the Milky Way gravitational potential and simultaneously testing different gravity theories directly from 6D phase-space surveys and without adopting dynamical models. We demonstrate that orbital energy distributions that are separable (i.e., independent of position) have an associated entropy that increases under wrong assumptions about the gravitational potential and/or gravity theory. Of known objects, 'cold' tidal streams from low-mass progenitors follow orbital distributions that most nearly satisfy the condition of separability. Although the orbits of tidally stripped stars are perturbed by the progenitor's self-gravity, systematic variations of the energy distribution can be quantified in terms of the cross-entropy of individual tails, giving further sensitivity to theoretical biases in the host potential. The feasibility of using the Minimum Entropy Method to test a wide range of gravity theories is illustrated by evolving restricted N-body models in a Newtonian potential and examining the changes in entropy introduced by Dirac, MONDian, and f(R) gravity modifications.
Neutron stars in a perturbative f(R) gravity model with strong magnetic fields
Cheoun, Myung-Ki; Deliduman, Cemsinan; Güngör, Can; Kele?, Vildan; Ryu, C.Y.; Kajino, Toshitaka; Mathews, Grant J. E-mail: cemsinan@msgsu.edu.tr E-mail: kelesvi@itu.edu.tr E-mail: kajino@nao.ac.jp
2013-10-01
In Kaluza-Klein electromagnetism it is natural to associate modified gravity with strong electromagnetic fields. Hence, in this paper we investigate the combined effects of a strong magnetic field and perturbative f(R) gravity on the structure of neutron stars. The effect of an interior strong magnetic field of about 10{sup 17?18} G on the equation of state is derived in the context of a quantum hadrodynamics (QHD) equation of state (EoS) including effects of the magnetic pressure and energy along with occupied Landau levels. Adopting a random orientation of interior field domains, we solve the modified spherically symmetric hydrostatic equilibrium equations derived for a gravity model with f(R) = R+?R{sup 2}. Effects of both the finite magnetic field and the modified gravity are detailed for various values of the magnetic field and the perturbation parameter ? along with a discussion of their physical implications. We show that there exists a parameter space of the modified gravity and the magnetic field strength, in which even a soft equation of state can accommodate a large ( > 2 M{sub s}un) maximum neutron star mass.
Christian, Joshua M.; Ho, Clifford Kuofei
2010-04-01
Understanding the effects of gravity and wind loads on concentrating solar power (CSP) collectors is critical for performance calculations and developing more accurate alignment procedures and techniques. This paper presents a rigorous finite-element model of a parabolic trough collector that is used to determine the impact of gravity loads on bending and displacements of the mirror facets and support structure. The geometry of the LUZ LS-2 parabolic trough collector was modeled using SolidWorks, and gravity-induced loading and displacements were simulated in SolidWorks Simulation. The model of the trough collector was evaluated in two positions: the 90{sup o} position (mirrors facing upward) and the 0{sup o} position (mirrors facing horizontally). The slope errors of the mirror facet reflective surfaces were found by evaluating simulated angular displacements of node-connected segments along the mirror surface. The ideal (undeformed) shape of the mirror was compared to the shape of the deformed mirror after gravity loading. Also, slope errors were obtained by comparing the deformed shapes between the 90{sup o} and 0{sup o} positions. The slope errors resulting from comparison between the deformed vs. undeformed shape were as high as {approx}2 mrad, depending on the location of the mirror facet on the collector. The slope errors resulting from a change in orientation of the trough from the 90{sup o} position to the 0{sup o} position with gravity loading were as high as {approx}3 mrad, depending on the location of the facet.
Limited-life cartridge primers
Makowiecki, Daniel M.; Rosen, Robert S.
2005-04-19
A cartridge primer which utilizes an explosive that can be designed to become inactive in a predetermined period of time: a limited-life primer. The explosive or combustible material of the primer is an inorganic reactive multilayer (RML). The reaction products of the RML are sub-micron grains of non-corrosive inorganic compounds that would have no harmful effects on firearms or cartridge cases. Unlike use of primers containing lead components, primers utilizing RML's would not present a hazard to the environment. The sensitivity of an RML is determined by the physical structure and the stored interfacial energy. The sensitivity lowers with time due to a decrease in interfacial energy resulting from interdiffusion of the elemental layers. Time-dependent interdiffusion is predictable, thereby enabling the functional lifetime of an RML primer to be predetermined by the initial thickness and materials selection of the reacting layers.
Limited-life cartridge primers
Makowiecki, D.M.; Rosen, R.S.
1998-06-30
A cartridge primer is described which utilizes an explosive that can be designed to become inactive in a predetermined period of time: a limited-life primer. The explosive or combustible material of the primer is an inorganic reactive multilayer (RML). The reaction products of the RML are sub-micron grains of non-corrosive inorganic compounds that would have no harmful effects on firearms or cartridge cases. Unlike use of primers containing lead components, primers utilizing RML`s would not present a hazard to the environment. The sensitivity of an RML is determined by the physical structure and the stored interfacial energy. The sensitivity lowers with time due to a decrease in interfacial energy resulting from interdiffusion of the elemental layers. Time-dependent interdiffusion is predictable, thereby enabling the functional lifetime of an RML primer to be predetermined by the initial thickness and materials selection of the reacting layers. 10 figs.
Limited-life cartridge primers
Makowiecki, Daniel M.; Rosen, Robert S.
1998-01-01
A cartridge primer which utilizes an explosive that can be designed to become inactive in a predetermined period of time: a limited-life primer. The explosive or combustible material of the primer is an inorganic reactive multilayer (RML). The reaction products of the RML are sub-micron grains of non-corrosive inorganic compounds that would have no harmful effects on firearms or cartridge cases. Unlike use of primers containing lead components, primers utilizing RML's would not present a hazard to the environment. The sensitivity of an RML is determined by the physical structure and the stored interfacial energy. The sensitivity lowers with time due to a decrease in interfacial energy resulting from interdiffusion of the elemental layers. Time-dependent interdiffusion is predictable, thereby enabling the functional lifetime of an RML primer to be predetermined by the initial thickness and materials selection of the reacting layers.
WaikatoLink Limited | Open Energy Information
OpenEI (Open Energy Information) [EERE & EIA]
Limited Jump to: navigation, search Name: WaikatoLink Limited Place: New Zealand Sector: Services Product: General Financial & Legal Services ( Individual Angel network )...
Power Projects Limited | Open Energy Information
OpenEI (Open Energy Information) [EERE & EIA]
Limited Jump to: navigation, search Name: Power Projects Limited Address: PO Box 25456 Panama Street Place: Wellington Zip: 6146 Region: New Zealand Sector: Marine and Hydrokinetic...
Nufcor International Limited Nufcor | Open Energy Information
OpenEI (Open Energy Information) [EERE & EIA]
Limited (Nufcor) Place: United Kingdom Sector: Services Product: UK-based uranium marketing services company. References: Nufcor International Limited (Nufcor)1 This article...
Voith Hydro Wavegen Limited | Open Energy Information
OpenEI (Open Energy Information) [EERE & EIA]
Voith Hydro Wavegen Limited Jump to: navigation, search Name: Voith Hydro Wavegen Limited Region: United Kingdom Sector: Marine and Hydrokinetic Website: www.wavegen.co.uk This...
Cape Systems Limited | Open Energy Information
OpenEI (Open Energy Information) [EERE & EIA]
Limited Jump to: navigation, search Name: Cape Systems Limited Place: Rock Sound, Bahamas Sector: Services Product: Offers installation and site surveying services for clean...
SRSL Ethanol Limited | Open Energy Information
OpenEI (Open Energy Information) [EERE & EIA]
SRSL Ethanol Limited Jump to: navigation, search Name: SRSL Ethanol Limited Place: Mumbai, Maharashtra, India Product: Mumbai-based ethanol subsidiary of Shree Renuka Sugars...
Rix Biodiesel Limited | Open Energy Information
OpenEI (Open Energy Information) [EERE & EIA]
Rix Biodiesel Limited Jump to: navigation, search Name: Rix Biodiesel Limited Place: Hull, United Kingdom Zip: HU8 7JR Product: Manufacture, blends and resells biodiesel....
Tidal Energy Limited | Open Energy Information
OpenEI (Open Energy Information) [EERE & EIA]
Limited Jump to: navigation, search Name: Tidal Energy Limited (TEL) Place: Cardiff, Wales, United Kingdom Zip: CF23 8RS Product: Tidal stream device developer. Coordinates:...
China Innovation Investment Limited | Open Energy Information
OpenEI (Open Energy Information) [EERE & EIA]
Innovation Investment Limited Jump to: navigation, search Name: China Innovation Investment Limited Place: Hong Kong Sector: Solar Product: Hong Kong-listed alternative energy...
Gujarat Ambuja Cements Limited | Open Energy Information
OpenEI (Open Energy Information) [EERE & EIA]
Limited Jump to: navigation, search Name: Gujarat Ambuja Cements Limited Place: Mumbai, India Zip: 400 021 Sector: Biomass Product: Indian cement company. the company...
Catamount Energy Limited | Open Energy Information
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Limited Jump to: navigation, search Name: Catamount Energy Limited Place: United Kingdom Sector: Wind energy Product: Wind power project developer working on projects in Scotland....
Central Electronics Limited CEL | Open Energy Information
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Electronics Limited CEL Jump to: navigation, search Name: Central Electronics Limited (CEL) Place: Sahibabad, Uttar Pradesh, India Zip: 201010 Sector: Solar Product: String...
Clipper Windpower Europe Limited | Open Energy Information
OpenEI (Open Energy Information) [EERE & EIA]
Clipper Windpower Europe Limited Jump to: navigation, search Name: Clipper Windpower Europe Limited Place: London, Greater London, United Kingdom Zip: SE1 7TJ Sector: Wind energy...
BFC Solutions Limited | Open Energy Information
OpenEI (Open Energy Information) [EERE & EIA]
BFC Solutions Limited Jump to: navigation, search Name: BFC Solutions Limited Place: Taunton, England, United Kingdom Zip: TA1 PEJ Sector: Carbon Product: Somerset-based...
Greenergy Biofuels Limited | Open Energy Information
OpenEI (Open Energy Information) [EERE & EIA]
Biofuels Limited Jump to: navigation, search Name: Greenergy Biofuels Limited Place: London, Greater London, United Kingdom Zip: WC1V 7BD Sector: Biofuels Product: Imports, blends...
Transmission Capital Limited | Open Energy Information
OpenEI (Open Energy Information) [EERE & EIA]
Transmission Capital Limited Jump to: navigation, search Name: Transmission Capital Limited Place: London, United Kingdom Zip: EC2V 7HR Sector: Renewable Energy, Services Product:...
Impact Capital Partners Limited | Open Energy Information
OpenEI (Open Energy Information) [EERE & EIA]
Capital Partners Limited Jump to: navigation, search Name: Impact Capital Partners Limited Place: Los Angeles, California Zip: CA 90067-1509 Product: Los Angeles-based, investment...
Universal Carbon Credits Limited | Open Energy Information
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Universal Carbon Credits Limited Jump to: navigation, search Name: Universal Carbon Credits Limited Place: London, England, United Kingdom Zip: EC3A6DF Sector: Carbon Product:...
Carbon Trust Enterprises Limited | Open Energy Information
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Enterprises Limited Jump to: navigation, search Name: Carbon Trust Enterprises Limited Place: London, United Kingdom Zip: WC2A 2AZ Sector: Carbon Product: Carbon Trust Enterprises...
Carbon Limiting Technologies | Open Energy Information
OpenEI (Open Energy Information) [EERE & EIA]
Limiting Technologies Jump to: navigation, search Name: Carbon Limiting Technologies Place: London, Greater London, United Kingdom Zip: N1 8HA Sector: Carbon Product: UK-based...
Harvard Dedicated Energy Limited | Open Energy Information
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Harvard Dedicated Energy Limited Jump to: navigation, search Name: Harvard Dedicated Energy Limited Place: Massachusetts Phone Number: (617) 495-5560 Website: www.energyandfaciliti...
United Biofuels Private Limited | Open Energy Information
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United Biofuels Private Limited Jump to: navigation, search Name: United Biofuels Private Limited Place: Tamil Nadu, India Sector: Biomass Product: India-based owner and operator...
Mauktika Energy Limited MEL | Open Energy Information
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Mauktika Energy Limited MEL Jump to: navigation, search Name: Mauktika Energy Limited (MEL) Place: Hyderabad, Andhra Pradesh, India Zip: 500033 Sector: Renewable Energy Product:...
United Group Limited | Open Energy Information
OpenEI (Open Energy Information) [EERE & EIA]
Limited Jump to: navigation, search Name: United Group Limited Place: Perth, Western Australia, Australia Zip: 6001 Product: The United Group Resources (UGL) division is an EPC and...
Renewable Fuels Limited RFL | Open Energy Information
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Limited RFL Jump to: navigation, search Name: Renewable Fuels Limited (RFL) Place: York, United Kingdom Zip: YO19 6ET Sector: Biomass Product: Supplies various biomass fuels and...
Danes, Z.F.; Phillips, W.M.
1983-02-01
Since 1974, the Division of Geology and Earth Resources, in conjunction with the US Department of Energy, has supported gravity studies in the Cascade Mountains of Washington State. Results of the Cascade gravity project are summarized graphically as a complete Bouguer gravity anomaly map of the Cascade Mountains, Washington (Danes and Phillips, 1983). This report provides supplementary data and documentation for the complete Bouguer gravity anomaly map. Presented are principal gravity facts, simple Bouguer and Free-air gravity anomalies, computational methods, error analysis and a discussion of terrain corrections.
Relativistic redshifts in quasar broad lines
Tremaine, Scott; Shen, Yue; Liu, Xin; Loeb, Abraham E-mail: yshen@obs.carnegiescience.edu E-mail: aloeb@cfa.harvard.edu
2014-10-10
The broad emission lines commonly seen in quasar spectra have velocity widths of a few percent of the speed of light, so special- and general-relativistic effects have a significant influence on the line profile. We have determined the redshift of the broad HÎ˛ line in the quasar rest frame (determined from the core component of the [O III] line) for over 20,000 quasars from the Sloan Digital Sky Survey Data Release 7 quasar catalog. The mean redshift as a function of line width is approximately consistent with the relativistic redshift that is expected if the line originates in a randomly oriented Keplerian disk that is obscured when the inclination of the disk to the line of sight exceeds âĽ30Â°-45Â°, consistent with simple active galactic nucleus unification schemes. This result also implies that the net line-of-sight inflow/outflow velocities in the broad-line region are much less than the Keplerian velocity when averaged over a large sample of quasars with a given line width.
Method and apparatus to trigger superconductors in current limiting devices
Yuan, Xing; Hazelton, Drew Willard; Walker, Michael Stephen
2004-10-26
A method and apparatus for magnetically triggering a superconductor in a superconducting fault current limiter to transition from a superconducting state to a resistive state. The triggering is achieved by employing current-carrying trigger coil or foil on either or both the inner diameter and outer diameter of a superconductor. The current-carrying coil or foil generates a magnetic field with sufficient strength and the superconductor is disposed within essentially uniform magnetic field region. For superconductor in a tubular-configured form, an additional magnetic field can be generated by placing current-carrying wire or foil inside the tube and along the center axial line.
The Penetrant System Monitoring (PSM) panel: Its use and limitations
Robinson, S.J. [Sherwin Inc., South Gate, CA (United States)
1996-12-31
In the last several years, the Penetrant System Monitoring (PSM) panel has been increasingly used for purposes for which it was never intended. Intended originally for use by penetrant system operators, the PSM panel is increasingly being used by material control departments and by process engineering departments. This paper`s purpose is to describe and give guidance concerning the proper use and maintenance of PSM panels. It recounts the evolution of penetrant system test panels, and compares how the different types of panels are made. It discusses the limitations of the PSM panel as used by the material control department, the process engineering department, and the production line.
Fermi LAT Search for Photon Lines from 30 to 200 GeV
Abdo, A.A.; Ackermann, M.; Ajello, M.; Atwood, W.B.; Baldini, L.; Ballet, J.; Barbiellini, G.; Bastieri, D.; Bechtol, K.; Bellazzini, R.; Berenji, B.; Bloom, E.D.; Bonamente, E.; Borgland, A.W.; Bouvier, A.; Bregeon, J.; Brez, A.; Brigida, M.; Bruel, P.; Burnett, T.H.; Buson, S.; /Padua U. /Barcelona, IEEC /Stanford U. /SLAC /IASF, Milan /Padua U. /DAPNIA, Saclay /INFN, Perugia /Perugia U. /NASA, Goddard /JAXA, Sagamihara /NASA, Goddard /Maryland U., Baltimore County /Naval Research Lab, Wash., D.C. /George Mason U. /Stanford U. /SLAC /Perugia U. /Stanford U. /SLAC /Montpellier U. /Stockholm U. /Stockholm U., OKC /Naval Research Lab, Wash., D.C. /Udine U. /INFN, Trieste /Bari U. /INFN, Bari /Stanford U. /SLAC /CENBG, Gradignan /Stanford U. /SLAC /Montpellier U. /Bari U. /INFN, Bari /Ecole Polytechnique /Stanford U. /SLAC /Ecole Polytechnique /Udine U. /INFN, Trieste /Hiroshima U. /Stanford U. /SLAC /Bari U. /INFN, Bari /INFN, Bari /ASDC, Frascati /NASA, Goddard /Penn State U. /Maryland U. /INFN, Perugia /Perugia U. /Bari U. /INFN, Bari /Stanford U. /SLAC /DAPNIA, Saclay /Naval Research Lab, Wash., D.C. /Bonn, Max Planck Inst., Radioastron. /Alabama U., Huntsville /Padua U. /INFN, Padua /ICREA, Barcelona /NASA, Goddard /Ecole Polytechnique /Taiwan, Natl. Taiwan U. /Ohio State U. /Stockholm U., OKC /Royal Inst. Tech., Stockholm /Stanford U. /SLAC /UC, Santa Cruz /Naval Research Lab, Wash., D.C. /Stanford U. /SLAC /Hiroshima U. /Waseda U. /Tokyo Inst. Tech. /Wako, RIKEN /Washington U., Seattle /Toulouse, CESR /INFN, Pisa /Stanford U. /SLAC /INFN, Pisa /Stockholm U. /Stockholm U., OKC /INFN, Trieste /Trieste U. /Bari U. /INFN, Bari /CENBG, Gradignan /Naval Research Lab, Wash., D.C. /INFN, Perugia /Perugia U. /Naval Research Lab, Wash., D.C. /George Mason U. /INFN, Bari /NASA, Goddard /Maryland U. /Stockholm U. /Stockholm U., OKC /Stanford U. /SLAC /Hiroshima U. /JAXA, Sagamihara /NASA, Goddard /Maryland U. /Bari U. /INFN, Bari /Stanford U. /SLAC /Rome U.,Tor Vergata /Stanford U. /SLAC /Denver U. /Montpellier U. /Hiroshima U. /INFN, Pisa /Garching, Max Planck Inst., MPE /Denver U. /JAXA, Sagamihara /Stanford U. /SLAC /CENBG, Gradignan /Montpellier U. /INFN, Perugia /Perugia U. /INFN, Pisa /Montpellier U. /Bari U. /INFN, Bari /INFN, Padua /Padua U. /INFN, Pisa /Innsbruck U. /Stanford U. /SLAC /CENBG, Gradignan /Stockholm U. /Stockholm U., OKC /UC, Santa Cruz /Barcelona, IEEC /Washington U., Seattle /UC, Santa Cruz /Taiwan, Natl. Taiwan U. /Ohio State U. /UC, Santa Cruz /NASA, Ames /UC, Santa Cruz /Stockholm U. /Stockholm U., OKC /INFN, Pisa /Unlisted /CENBG, Gradignan /Taiwan, Natl. Taiwan U. /Ohio State U. /INFN, Pisa /Bari U. /INFN, Bari /DAPNIA, Saclay /Naval Research Lab, Wash., D.C. /Purdue U. /Stanford U. /SLAC /Hiroshima U. /Stanford U. /SLAC /INFN, Padua /Padua U. /DAPNIA, Saclay /ICREA, Barcelona /Barcelona, IEEC /Stanford U. /SLAC /JAXA, Sagamihara /NASA, Goddard /Maryland U., Baltimore County /Toulouse, CESR /Rome U.,Tor Vergata /Banca di Roma /Stanford U. /SLAC /Taiwan, Natl. Taiwan U. /Ohio State U. /Naval Research Lab, Wash., D.C. /Royal Inst. Tech., Stockholm /Tsukuba U., GSPAS /Kalmar U. /Stockholm U., OKC /UC, Santa Cruz
2010-05-26
Dark matter (DM) particle annihilation or decay can produce monochromatic {gamma}-rays readily distinguishable from astrophysical sources. {gamma}-ray line limits from 30 GeV to 200 GeV obtained from 11 months of Fermi Large Area Space Telescope data from 20-300 GeV are presented using a selection based on requirements for a {gamma}-ray line analysis, and integrated over most of the sky. We obtain {gamma}-ray line flux upper limits in the range 0.6-4.5 x 10{sup -9} cm{sup -2}s{sup -1}, and give corresponding DM annihilation cross-section and decay lifetime limits. Theoretical implications are briefly discussed.
An experimental study of pool boiling heat transfer in reduced gravity
Shatto, D.P.; Renzi, K.I.; Peterson, G.P.; Morris, T.K.; Aaron, J.W.
1996-12-31
Experiments were performed in which pool boiling of pure water at reduced pressures was observed for behavior of the critical heatflux (CHF) and nucleate boiling heat transfer coefficients in a reduced gravitational environment. The experiments took place while alternating between microgravity and g/g{sub o} = 1.8 during parabolic flights aboard the NASA 930 (KC-135A). Heat transfer data were also obtained at Martian gravity levels (g/g{sub o} = 1/3). Parts of the test chamber were constructed of transparent materials to allow viewing and recording of the various boiling regimes encountered during the experiments. Results indicate that the onset of nucleate boiling occurred at lower heat fluxes in reduced gravity, resulting in higher two-phase heat transfer coefficients for g/g{sub o} < 1 than for g/g{sub o} = 1.8. In addition, the results indicate a significant reduction in the critical heat flux under reduced gravity conditions.
Thermodynamics of asymptotically flat charged black holes in third order Lovelock gravity
Dehghani, M.H.; Shamirzaie, M.
2005-12-15
We present a new class of asymptotically flat charge static solutions in third order Lovelock gravity. These solutions present black hole solutions with two inner and outer event horizons, extreme black holes, or naked singularities provided the parameters of the solutions are chosen suitable. We find that the uncharged asymptotically flat solutions can present black holes with two inner and outer horizons. This kind of solution does not exist in Einstein or Gauss-Bonnet gravity, and it is a special effect in third order Lovelock gravity. We compute temperature, entropy, charge, electric potential, and mass of the black hole solutions, and find that these quantities satisfy the first law of thermodynamics. We also perform a stability analysis by computing the determinant of the Hessian matrix of the mass with respect to its thermodynamic variables in both the canonical and the grand-canonical ensembles, and show that there exists only an intermediate stable phase.
NSLS-II Transport Line Progress
Fliller R. P.; Wahl, W.; Anderson, A.; Benish, B.; DeBoer, W.; Ganetis, G.; Heese, R.; Hseuh, H.-C.; Hu, J.-P.; Johanson, M.P.; Kosciuk, B.N.; Padrazo, D.; Roy, K.; Shaftan, T.; Singh, O.; Tuozzolo, J.; Wang, G.
2012-05-20
The National Synchrotron Light Source II (NSLS-II) is a state-of-the-art 3-GeV third generation light source currently under construction at Brookhaven National Laboratory. The NSLS-II injection system consists of a 200 MeV linac, a 3-GeV booster synchrotron and associated transfer lines. The first part of the Linac to Booster Transport (LBT) line has been installed for linac commissioning. This part includes all components necessary to commission the NSLS-II linac. The second part of this transport line is undergoing installation. Initial results of hardware commissioning will be discussed. The Booster to Storage Ring (BSR) transport line underwent a design review. The first part of the BSR transport line, consisting of all components necessary to commission the booster will be installed in 2012 for booster commissioning. We report on the final design of the BSR line along with the plan to commission the booster.
Single transmission line data acquisition system
Fasching, George E.
1984-01-01
A single transmission line interrogated multiple channel data acquisition system is provided in which a plurality of remote station/sensors monitor specific process variables and transmit measurement values over the single transmission line to a master station when addressed by the master station. Power for all remote stations (up to 980) is provided by driving the line with constant voltage supplied from the master station and automatically maintained independent of the number of remote stations directly connected to the line. The transmission line can be an RG-62 coaxial cable with lengths up to about 10,000 feet with branches up to 500 feet. The remote stations can be attached randomly along the line. The remote stations can be scanned at rates up to 980 channels/second.
Shear wall ultimate drift limits
Duffey, T.A.; Goldman, A.; Farrar, C.R.
1994-04-01
Drift limits for reinforced-concrete shear walls are investigated by reviewing the open literature for appropriate experimental data. Drift values at ultimate are determined for walls with aspect ratios ranging up to a maximum of 3.53 and undergoing different types of lateral loading (cyclic static, monotonic static, and dynamic). Based on the geometry of actual nuclear power plant structures exclusive of containments and concerns regarding their response during seismic (i.e.,cyclic) loading, data are obtained from pertinent references for which the wall aspect ratio is less than or equal to approximately 1, and for which testing is cyclic in nature (typically displacement controlled). In particular, lateral deflections at ultimate load, and at points in the softening region beyond ultimate for which the load has dropped to 90, 80, 70, 60, and 50 percent of its ultimate value, are obtained and converted to drift information. The statistical nature of the data is also investigated. These data are shown to be lognormally distributed, and an analysis of variance is performed. The use of statistics to estimate Probability of Failure for a shear wall structure is illustrated.
Microsoft Word - STO Comments on Clean Line Application under...
Energy.gov [DOE] (indexed site)
Clean Line Transmission Line Project ("Clean Line Project" or "Project"). ... "objective of integrating more renewable resources onto the grid," 1 However, after reviewing Section ...
Salt Waste Processing Facility, Line Management Review Board...
Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)
Line Management Review Board Charter Salt Waste Processing Facility, Line Management Review Board Charter The Line Management Review Board (LMRB) serves an important oversight ...
Electromagnetic field limits set by the V-Curve.
Warne, Larry Kevin; Jorgenson, Roy Eberhardt; Hudson, Howard Gerald
2014-07-01
When emitters of electromagnetic energy are operated in the vicinity of sensitive components, the electric field at the component location must be kept below a certain level in order to prevent the component from being damaged, or in the case of electro-explosive devices, initiating. The V-Curve is a convenient way to set the electric field limit because it requires minimal information about the problem configuration. In this report we will discuss the basis for the V-Curve. We also consider deviations from the original V-Curve resulting from inductive versus capacitive antennas, increases in directivity gain for long antennas, decreases in input impedance when operating in a bounded region, and mismatches dictated by transmission line losses. In addition, we consider mitigating effects resulting from limited antenna sizes.
Zhao, Gong-Bo
2014-04-01
Based on a suite of N-body simulations of the Hu-Sawicki model of f(R) gravity with different sets of model and cosmological parameters, we develop a new fitting formula with a numeric code, MGHalofit, to calculate the nonlinear matter power spectrum P(k) for the Hu-Sawicki model. We compare the MGHalofit predictions at various redshifts (z ? 1) to the f(R) simulations and find that the relative error of the MGHalofit fitting formula of P(k) is no larger than 6% at k ? 1 h Mpc{sup –1} and 12% at k in (1, 10] h Mpc{sup –1}, respectively. Based on a sensitivity study of an ongoing and a future spectroscopic survey, we estimate the detectability of a signal of modified gravity described by the Hu-Sawicki model using the power spectrum up to quasi-nonlinear scales.
Holographic superconductors in Gauss-Bonnet gravity with Born-Infeld electrodynamics
Jing Jiliang; Wang Liancheng; Pan Qiyuan; Chen Songbai
2011-03-15
We investigate the holographic superconductors in Gauss-Bonnet gravity with Born-Infeld electrodynamics. We find that the Gauss-Bonnet constant, the model parameters, and the Born-Infeld coupling parameter will affect the formation of the scalar hair, the transition point of the phase transition from the second order to the first order, and the relation connecting the gap frequency in conductivity with the critical temperature. The combination of Gauss-Bonnet gravity and the Born-Infeld electrodynamics provides richer physics in the phase transition and the condensation of the scalar hair.
,"Domestic Crude Oil First Purchase Prices by API Gravity"
Energy Information Administration (EIA) (indexed site)
API Gravity" ,"Click worksheet name or tab at bottom for data" ,"Worksheet Name","Description","# Of Series","Frequency","Latest Data for" ,"Data 1","Domestic Crude Oil First Purchase Prices by API Gravity",6,"Monthly","8/2016","10/15/1993" ,"Release Date:","11/1/2016" ,"Next Release Date:","12/1/2016" ,"Excel File
Quasispherical gravitational collapse in 5D Einstein-Gauss-Bonnet gravity
Ghosh, Sushant G.; Jhingan, S.
2010-07-15
We obtain a general five-dimensional quasispherical collapsing solutions of irrotational dust in Einstein gravity with the Gauss-Bonnet combination of quadratic curvature terms. These solutions are a generalization, to Einstein-Gauss-Bonnet gravity, of the five-dimensional quasispherical Szkeres like collapsing solutions in general relativity. It is found that the collapse proceeds in the same way as in the analogous spherical collapse, i.e., there exists regular initial data such that the collapse proceed to form naked singularities violating cosmic censorship conjecture. The effect of Gauss-Bonnet quadratic curvature terms on the formation and locations of the apparent horizon is deduced.
Color-kinematics duality for pure Yang-Mills and gravity at one and two
Office of Scientific and Technical Information (OSTI)
loops (Journal Article) | SciTech Connect Color-kinematics duality for pure Yang-Mills and gravity at one and two loops Citation Details In-Document Search Title: Color-kinematics duality for pure Yang-Mills and gravity at one and two loops Authors: Bern, Zvi ; Davies, Scott ; Dennen, Tristan ; Huang, Yu-tin ; Nohle, Josh Publication Date: 2015-08-31 OSTI Identifier: 1213605 Grant/Contract Number: FG03-91ER40662; SC0007859; SC0008279 Type: Publisher's Accepted Manuscript Journal Name:
Detonator comprising a nonlinear transmission line
Elizondo-Decanini, Juan M
2014-12-30
Detonators are described herein. In a general embodiment, the detonator includes a nonlinear transmission line that has a variable capacitance. Capacitance of the nonlinear transmission line is a function of voltage on the nonlinear transmission line. The nonlinear transmission line receives a voltage pulse from a voltage source and compresses the voltage pulse to generate a trigger signal. Compressing the voltage pulse includes increasing amplitude of the voltage pulse and decreasing length of the voltage pulse in time. An igniter receives the trigger signal and detonates an explosive responsive to receipt of the trigger signal.
Strengthening Line Management Oversight and Federal Monitoring...
Office of Environmental Management (EM)
Strengthening Line Management Oversight and Federal Monitoring of Nuclear Facilities Standard Review Plan Volume 4 - Nuclear Safety Basis Program Review During Facility ...
Strengthening Line Management Oversight and Federal Monitoring...
Office of Environmental Management (EM)
4 Strengthening Line Management Oversight and Federal Monitoring of Nuclear Facilities Standard Review Plan Commercial Grade Dedication (CGD) August 2013 2 of 14 OFFICE OF ...
Strengthening Line Management Oversight and Federal Monitoring...
Office of Environmental Management (EM)
Strengthening Line Management Oversight and Federal Monitoring of Nuclear Facilities Standard Review Plan Volume 2 -- Nuclear Safety Basis Program Review During Design February ...
Transmission Line Security Monitor: Final Report
John Svoboda
2011-04-01
The Electric Power Transmission Line Security Monitor System Operational Test is a project funded by the Technical Support Working Group (TSWG). TSWG operates under the Combating Terrorism Technical Support Office that functions under the Department of Defense. The Transmission Line Security Monitor System is based on technology developed by Idaho National Laboratory. The technology provides a means for real-time monitoring of physical threats and/or damage to electrical transmission line towers and conductors as well as providing operational parameters to transmission line operators to optimize transmission line operation. The end use is for monitoring long stretches of transmission lines that deliver electrical power from remote generating stations to cities and industry. These transmission lines are generally located in remote transmission line corridors where security infrastructure may not exist. Security and operational sensors in the sensor platform on the conductors take power from the transmission line and relay security and operational information to operations personnel hundreds of miles away without relying on existing infrastructure. Initiated on May 25, 2007, this project resulted in pre-production units tested in realistic operational environments during 2010. A technology licensee, Lindsey Manufacturing of Azusa California, is assisting in design, testing, and ultimately production. The platform was originally designed for a security monitoring mission, but it has been enhanced to include important operational features desired by electrical utilities.
DOE Sustainability Reporting Open Line Help Call
The Sustainability Performance Office (SPO) sponsors open line help calls to assist DOE sites and national laboratories with the annual sustainability reporting process. Representatives from the...
Supervisory Transmission Lines and Substation Maintenance Manager
(See Frequently Asked Questions for more information). Where would I be working? Western Area Power Administration Desert Southwest Region Transmission Lines and Substation Maintenance (G5200) 615...
MMW Drilling & Lining | Department of Energy
Energy.gov [DOE] (indexed site)
MMW Drilling & Lining presentation at the April 2013 peer review meeting held in Denver, Colorado. mmwdrillingpeer2013.pdf (1 MB) More Documents & Publications Microhole Arrays ...
Rohatgi, Upendra S. [Brookhaven National Laboratory (United States); Jo, Jae H. [Brookhaven National Laboratory (United States); Chung, Bub Dong [Brookhaven National Laboratory (United States); Takahashi, Hiroshi [Brookhaven National Laboratory (United States); Downar, Thomas J. [Purdue University (United States)
2004-01-15
Safety analyses of a proliferation-resistant, economically competitive, high-conversion boiling water reactor (HCBWR) fueled with fissile plutonium and fertile thorium oxide fuel elements, and with passive safety systems, are presented here. The HCBWR developed here is characterized by a very tight lattice with a relatively small water volume fraction in the core that therefore operates with a fast reactor neutron spectrum and a considerably improved neutron economy compared to the current generation of light water reactors. The tight lattice core has a very narrow flow channel with a hydraulic diameter less than half of the regular boiling water reactor (BWR) core and, thus, presents a special challenge to core cooling because of reduced water inventory and high friction in the core. The primary safety concern when reducing the moderator-to-fuel ratio and when using a tightly packed lattice arrangement is to maintain adequate cooling of the core during both normal operation and accident scenarios.In the preliminary HCBWR design, the core is placed in a vessel with a large chimney section, and the vessel is connected to the isolation condenser system (ICS). The vessel is placed in containment with the gravity driven cooling system (GDCS) and passive containment cooling system (PCCS) in a configuration similar to General Electric's simplified BWR (SBWR). The safety systems are similar to those of the SBWR; the ICS and PCCS are scaled with power. An internal recirculation pump is placed in the downcomer to augment the buoyancy head provided by the chimney since the buoyancy provided by the chimney alone could not generate sufficient recirculation in the vessel as the tight lattice configuration results in much larger friction in the core than with the SBWR.The constitutive relationships for RELAP5 are assessed for narrow channels, and as a result the heat transfer package is modified. The modified RELAP5 is used to simulate and analyze two of the most limiting events
THE SDSS-III APOGEE SPECTRAL LINE LIST FOR H-BAND SPECTROSCOPY
Shetrone, M.; Bizyaev, D.; Chojnowski, D.; Lawler, J. E.; Prieto, C. Allende; Zamora, O.; GarcĂa-HernĂˇndez, D. A.; Souto, D.; Smith, V. V.; Cunha, K.; Holtzman, J.; PĂ©rez, A. E. GarcĂa; Sobeck, J.; Majewski, S.; MĂ©szĂˇros, Sz.; Koesterke, L.; Zasowski, G.
2015-12-15
We present the H-band spectral line lists adopted by the Apache Point Observatory Galactic Evolution Experiment (APOGEE). The APOGEE line lists comprise astrophysical, theoretical, and laboratory sources from the literature, as well as newly evaluated astrophysical oscillator strengths and damping parameters. We discuss the construction of the APOGEE line list, which is one of the critical inputs for the APOGEE Stellar Parameters and Chemical Abundances Pipeline, and present three different versions that have been used at various stages of the project. The methodology for the newly calculated astrophysical line lists is reviewed. The largest of these three line lists contains 134,457 molecular and atomic transitions. In addition to the format adopted to store the data, the line lists are available in MOOG, Synspec, and Turbospectrum formats. The limitations of the line lists along with guidance for its use on different spectral types are discussed. We also present a list of H-band spectral features that are either poorly represented or completely missing in our line list. This list is based on the average of a large number of spectral fit residuals for APOGEE observations spanning a wide range of stellar parameters.
Soliton production with nonlinear homogeneous lines
Elizondo-Decanini, Juan M.; Coleman, Phillip D.; Moorman, Matthew W.; Petney, Sharon Joy Victor; Dudley, Evan C.; Youngman, Kevin; Penner, Tim Dwight; Fang, Lu; Myers, Katherine M.
2015-11-24
Low- and high-voltage Soliton waves were produced and used to demonstrate collision and compression using diode-based nonlinear transmission lines. Experiments demonstrate soliton addition and compression using homogeneous nonlinear lines. We built the nonlinear lines using commercially available diodes. These diodes are chosen after their capacitance versus voltage dependence is used in a model and the line design characteristics are calculated and simulated. Nonlinear ceramic capacitors are then used to demonstrate high-voltage pulse amplification and compression. The line is designed such that a simple capacitor discharge, input signal, develops soliton trains in as few as 12 stages. We also demonstrated outputmoreÂ Â» voltages in excess of 40 kV using Y5V-based commercial capacitors. The results show some key features that determine efficient production of trains of solitons in the kilovolt range.Â«Â less
Soliton production with nonlinear homogeneous lines
Elizondo-Decanini, Juan M.; Coleman, Phillip D.; Moorman, Matthew W.; Petney, Sharon Joy Victor; Dudley, Evan C.; Youngman, Kevin; Penner, Tim Dwight; Fang, Lu; Myers, Katherine M.
2015-11-24
Low- and high-voltage Soliton waves were produced and used to demonstrate collision and compression using diode-based nonlinear transmission lines. Experiments demonstrate soliton addition and compression using homogeneous nonlinear lines. We built the nonlinear lines using commercially available diodes. These diodes are chosen after their capacitance versus voltage dependence is used in a model and the line design characteristics are calculated and simulated. Nonlinear ceramic capacitors are then used to demonstrate high-voltage pulse amplification and compression. The line is designed such that a simple capacitor discharge, input signal, develops soliton trains in as few as 12 stages. We also demonstrated output voltages in excess of 40 kV using Y5V-based commercial capacitors. The results show some key features that determine efficient production of trains of solitons in the kilovolt range.
Large-scale structure in brane-induced gravity. I. Perturbation theory
Scoccimarro, Roman
2009-11-15
We study the growth of subhorizon perturbations in brane-induced gravity using perturbation theory. We solve for the linear evolution of perturbations taking advantage of the symmetry under gauge transformations along the extra-dimension to decouple the bulk equations in the quasistatic approximation, which we argue may be a better approximation at large scales than thought before. We then study the nonlinearities in the bulk and brane equations, concentrating on the workings of the Vainshtein mechanism by which the theory becomes general relativity (GR) at small scales. We show that at the level of the power spectrum, to a good approximation, the effect of nonlinearities in the modified gravity sector may be absorbed into a renormalization of the gravitational constant. Since the relation between the lensing potential and density perturbations is entirely unaffected by the extra physics in these theories, the modified gravity can be described in this approximation by a single function, an effective gravitational constant for nonrelativistic motion that depends on space and time. We develop a resummation scheme to calculate it, and provide predictions for the nonlinear power spectrum. At the level of the large-scale bispectrum, the leading order corrections are obtained by standard perturbation theory techniques, and show that the suppression of the brane-bending mode leads to characteristic signatures in the non-Gaussianity generated by gravity, generic to models that become GR at small scales through second-derivative interactions. We compare the predictions in this work to numerical simulations in a companion paper.
Existence of global weak solution for a reduced gravity two and a half layer model
Guo, Zhenhua Li, Zilai Yao, Lei
2013-12-15
We investigate the existence of global weak solution to a reduced gravity two and a half layer model in one-dimensional bounded spatial domain or periodic domain. Also, we show that any possible vacuum state has to vanish within finite time, then the weak solution becomes a unique strong one.
A scaling analysis of thermoacoustic convection in a zero-gravity environment
Krane, R.J.; Parang, M.
1982-01-01
This paper presents a scaling analysis of a one-dimensional thermoacoustic convection heat transfer process in a zero-gravity environment. The relative importance of the terms in the governing equations is discussed for different time scales without attempting to solve the equations. The scaling analysis suggests certain generalizations that can be made in this class of heat transfer problems.
Asymptotically (anti)-de Sitter solutions in Gauss-Bonnet gravity without a cosmological constant
Dehghani, M.H.
2004-09-15
In this paper I show that one can have asymptotically de Sitter, anti-de Sitter (AdS), and flat solutions in Gauss-Bonnet gravity without a cosmological constant term in field equations. First, I introduce static solutions whose three surfaces at fixed r and t have constant positive (k=1), negative (k=-1), or zero (k=0) curvature. I show that for k={+-}1 one can have asymptotically de Sitter, AdS, and flat spacetimes, while for the case of k=0, one has only asymptotically AdS solutions. Some of these solutions present naked singularities, while some others are black hole or topological black hole solutions. I also find that the geometrical mass of these five-dimensional spacetimes is m+2{alpha}|k|, which is different from the geometrical mass m of the solutions of Einstein gravity. This feature occurs only for the five-dimensional solutions, and is not repeated for the solutions of Gauss-Bonnet gravity in higher dimensions. Second, I add angular momentum to the static solutions with k=0, and introduce the asymptotically AdS charged rotating solutions of Gauss-Bonnet gravity. Finally, I introduce a class of solutions which yields an asymptotically AdS spacetime with a longitudinal magnetic field, which presents a naked singularity, and generalize it to the case of magnetic rotating solutions with two rotation parameters.
Some Cosmological Models for Poincare Gauge Gravity and Accelerated Expansion of the Universe
Mebarki, N.
2010-10-31
Two cosmological Models for the Poincare Gauge Gravity theory with a non vanishing torsion are proposed. It is shown that the torsion plays an important role in explaining the accelerated expansion of the universe. Some of the cosmological parameters are also expressed in terms of the redshift and the dark energy scenarios are discussed.
Entirely passive heat-pipe apparatus capable of operating against gravity
Koenig, D.R.
1981-02-11
The disclosure is directed to an entirely passive heat pipe apparatus capable of operating against gravity for vertical distances in the order of 3 to 7 and more. A return conduit into which an inert gas is introduced is used to lower the specific density of the working fluid so that it may be returned a greater vertical distance from condenser to evaporator.
Effective matter cosmologies of massive gravity I: non-physical fluids
Y?lmaz, Nejat Tevfik
2014-08-01
For the massive gravity, after decoupling from the metric equation we find a broad class of solutions of the Stückelberg sector by solving the background metric in the presence of a diagonal physical metric. We then construct the dynamics of the corresponding FLRW cosmologies which inherit effective matter contribution through the decoupling solution mechanism of the scalar sector.
Detection of an unidentified emission line in the stacked X-ray spectrum of galaxy clusters
Bulbul, Esra; Foster, Adam; Smith, Randall K.; Randall, Scott W.; Markevitch, Maxim; Loewenstein, Michael
2014-07-01
We detect a weak unidentified emission line at E = (3.55-3.57) ± 0.03 keV in a stacked XMM-Newton spectrum of 73 galaxy clusters spanning a redshift range 0.01-0.35. When the full sample is divided into three subsamples (Perseus, Centaurus+Ophiuchus+Coma, and all others), the line is seen at >3? statistical significance in all three independent MOS spectra and the PN 'all others' spectrum. It is also detected in the Chandra spectra of the Perseus Cluster. However, it is very weak and located within 50-110 eV of several known lines. The detection is at the limit of the current instrument capabilities. We argue that there should be no atomic transitions in thermal plasma at this energy. An intriguing possibility is the decay of sterile neutrino, a long-sought dark matter particle candidate. Assuming that all dark matter is in sterile neutrinos with m{sub s} = 2E = 7.1 keV, our detection corresponds to a neutrino decay rate consistent with previous upper limits. However, based on the cluster masses and distances, the line in Perseus is much brighter than expected in this model, significantly deviating from other subsamples. This appears to be because of an anomalously bright line at E = 3.62 keV in Perseus, which could be an Ar XVII dielectronic recombination line, although its emissivity would have to be 30 times the expected value and physically difficult to understand. Another alternative is the above anomaly in the Ar line combined with the nearby 3.51 keV K line also exceeding expectation by a factor of 10-20. Confirmation with Astro-H will be critical to determine the nature of this new line.
Biodiesel Energy Trading Limited | Open Energy Information
OpenEI (Open Energy Information) [EERE & EIA]
Limited Jump to: navigation, search Name: Biodiesel Energy Trading Limited Place: London, United Kingdom Zip: W1J 8DY Product: London-based company focused on trading of biodiesel....
EU Energy Wind Limited | Open Energy Information
OpenEI (Open Energy Information) [EERE & EIA]
Wind Limited Jump to: navigation, search Name: EU Energy (Wind) Limited Place: Central Milton Keynes, United Kingdom Zip: K9 1LH Sector: Wind energy Product: The company will be...
Graduate Program Time Limits and Work Schedules
U.S. Department of Energy (DOE) - all webpages (Extended Search)
Time Limits and Work Schedules Graduate Program Time Limits and Work Schedules Point your career towards Los Alamos Lab: work with the best minds on the planet in an inclusive...
Undergraduate Program Time Limits and Work Schedules
U.S. Department of Energy (DOE) - all webpages (Extended Search)
Time Limits and Work Schedules Undergraduate Program Time Limits and Work Schedules Point your career towards Los Alamos Lab: work with the best minds on the planet in an inclusive...
Lead Hero Limited | Open Energy Information
OpenEI (Open Energy Information) [EERE & EIA]
Hero Limited Jump to: navigation, search Name: Lead Hero Limited Place: China Product: China-based company that holds a 100% interest in XiAn Lv Jing and a 15.05% interest in...
GenDrive Limited | Open Energy Information
OpenEI (Open Energy Information) [EERE & EIA]
GenDrive Limited Jump to: navigation, search Name: GenDrive Limited Place: Cambridge, United Kingdom Zip: CB23 3GY Sector: Renewable Energy, Solar, Wind energy Product: Developing...
Mistral Invest Limited | Open Energy Information
OpenEI (Open Energy Information) [EERE & EIA]
Mistral Invest Limited Jump to: navigation, search Name: Mistral Invest Limited Place: London, United Kingdom Zip: W1U 7DW Sector: Wind energy Product: Private Equity Fund aiming...
Zebec Biogas Limited | Open Energy Information
OpenEI (Open Energy Information) [EERE & EIA]
Zebec Biogas Limited Jump to: navigation, search Name: Zebec Biogas Limited Place: Glasgow, Scotland, United Kingdom Zip: G12 9JD Product: Sotland-based biogas company. The firm is...
IT Power Limited | Open Energy Information
OpenEI (Open Energy Information) [EERE & EIA]
IT Power Limited Jump to: navigation, search Name: IT Power Limited Place: Basingstoke, England, United Kingdom Zip: RG24 8AG Sector: Renewable Energy Product: IT Power is a...
Exorka International Limited | Open Energy Information
OpenEI (Open Energy Information) [EERE & EIA]
Exorka International Limited is a specialist developer of low-temperature geothermal electricity generation, incorporated in England. References: Exorka International...
Undergraduate Program Time Limits and Work Schedules
U.S. Department of Energy (DOE) - all webpages (Extended Search)
Time Limits and Work Schedules Undergraduate Program Time Limits and Work Schedules Point your career towards Los Alamos Lab: work with the best minds on the planet in an inclusive environment that is rich in intellectual vitality and opportunities for growth. Contact Student Programs (505) 665-0987 Email Time limits The length of participation in the undergraduate program is limited to a maximum of six years for students pursuing a bachelor's degree and three years for students pursuing an
Limited English Proficiency | Department of Energy
Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)
Limited English Proficiency Limited English Proficiency On August 11, 2000, President Clinton signed Executive Order 13166, "Improving Access to Services for Persons with Limited English Proficiency." The Executive Order requires federal agencies, including the Department of Energy, to examine the programs and services they provide, to determine whether there is a need for language assistance for persons with Limited English proficiency (LEP) related to their programs and services, and
Akhter Solar Limited | Open Energy Information
OpenEI (Open Energy Information) [EERE & EIA]
Islamabad, Pakistan Product: Owns a 3MW module assembly line in Pakistan, which uses Q-Cells cells. Coordinates: 33.709839, 73.075912 Show Map Loading map......
High temperature superconducting fault current limiter
Hull, John R.
1997-01-01
A fault current limiter (10) for an electrical circuit (14). The fault current limiter (10) includes a high temperature superconductor (12) in the electrical circuit (14). The high temperature superconductor (12) is cooled below its critical temperature to maintain the superconducting electrical properties during operation as the fault current limiter (10).
High temperature superconducting fault current limiter
Hull, J.R.
1997-02-04
A fault current limiter for an electrical circuit is disclosed. The fault current limiter includes a high temperature superconductor in the electrical circuit. The high temperature superconductor is cooled below its critical temperature to maintain the superconducting electrical properties during operation as the fault current limiter. 15 figs.
Primordial magnetic field limits from cosmological data
Kahniashvili, Tina [McWilliams Center for Cosmology and Department of Physics, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, Pennsylvania 15213 (United States); Department of Physics, Laurentian University, Ramsey Lake Road, Sudbury, Ontario P3E 2C (Canada); Abastumani Astrophysical Observatory, Ilia State University, 2A Kazbegi Ave, Tbilisi, GE-0160 (Georgia); Tevzadze, Alexander G. [Abastumani Astrophysical Observatory, Ilia State University, 2A Kazbegi Ave, Tbilisi, GE-0160 (Georgia); Faculty of Exact and Natural Sciences, Tbilisi State University, 1 Chavchavadze Avenue, Tbilisi, GE-0128 (Georgia); Sethi, Shiv K. [McWilliams Center for Cosmology and Department of Physics, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, Pennsylvania 15213 (United States); Raman Research Institute, Sadashivanagar, Bangalore 560080 (India); Pandey, Kanhaiya [Raman Research Institute, Sadashivanagar, Bangalore 560080 (India); Ratra, Bharat [Department of Physics, Kansas State University, 116 Cardwell Hall, Manhattan, Kansas 66506 (United States)
2010-10-15
We study limits on a primordial magnetic field arising from cosmological data, including that from big bang nucleosynthesis, cosmic microwave background polarization plane Faraday rotation limits, and large-scale structure formation. We show that the physically relevant quantity is the value of the effective magnetic field, and limits on it are independent of how the magnetic field was generated.
Computing Criticality of Lines in Power Systems
Pinar, Ali; Reichert, Adam; Lesieutre, Bernard
2006-10-13
We propose a computationally efficient method based onnonlinear optimization to identify critical lines, failure of which cancause severe blackouts. Our method computes criticality measure for alllines at a time, as opposed to detecting a single vulnerability,providing a global view of the system. This information on criticality oflines can be used to identify multiple contingencies by selectivelyexploring multiple combinations of broken lines. The effectiveness of ourmethod is demonstrated on the IEEE 30 and 118 bus systems, where we canvery quickly detect the most critical lines in the system and identifysevere multiple contingencies.
Electrical Transmission Line Diametrical Retention Mechanism
Hall, David R.; Hall, Jr., H. Tracy; Pixton, David; Dahlgren, Scott; Sneddon, Cameron; Briscoe, Michael; Fox, Joe
2006-01-03
The invention is a mechanism for retaining an electrical transmission line. In one embodiment of the invention it is a system for retaining an electrical transmission line within downhole components. The invention allows a transmission line to be attached to the internal diameter of drilling components that have a substantially uniform drilling diameter. In accordance with one aspect of the invention, the system includes a plurality of downhole components, such as sections of pipe in a drill string, drill collars, heavy weight drill pipe, and jars. The system also includes a coaxial cable running between the first and second end of a drill pipe, the coaxial cable having a conductive tube and a conductive core within it. The invention allows the electrical transmission line to withstand the tension and compression of drill pipe during routine drilling cycles.
Corona losses in HVdc bipolar lines
Corbellini, U.; Pelacchi, P.
1996-07-01
The problem related to the prediction of corona losses in HVdc bipolar lines has been solved, in the past, by means of semi-empirical monomial formulae. However, the proposed formulae that are simpler to use do not always give adequate calculation precision, while the formulae that provide the closest results require implicit functions of different complexity, which are difficult to apply; moreover, it is not possible to understand clearly what influence the variations of the different line parameters have on the losses themselves. The new monomial semi-empirical relationship, proposed to predict the corona losses in HVdc bipolar lines, is very simple to use; it highlights the dependence of power losses due to the corona effect by the different line parameters. The formula has been developed by elaborating a considerable amount of available experimental data.
Electrician - Foreman II (Transmission Lines & Substations) ...
Energy.gov [DOE] (indexed site)
Region Transmission Lines and Substation Maintenance (G5200) 615 S. 43rd Avenue Phoenix, AZ 85009 Duty Location is Page, AZ Find out more about living conditions at this...
Temperatures in the blast furnace refractory lining
Hebel, R.; Streuber, C.; Steiger, R.; Jeschar, R.
1995-12-01
The campaign life duration of a blast furnace is mainly determined by the condition of the refractory lining in heavy-duty zones such as the hearth, bosh, belly and lower stack. To achieve a desired lifetime, the temperature of the lining in these areas thereby proved to be the decisive controllable parameter. Low operating temperatures result in prolonged service life and are attained through high cooling efficiency. Besides the refractory grade chosen, the wear profile is mainly determined by the type of cooling system applied and the cooling intensity. Therefore, an appropriate compromise between long service life and energy losses has to be found in each case. In order to predict the service life of a lining it is important to know the wear condition at all times during the campaign. The paper describes the approaches the authors have made so far on European blast furnaces, on a theoretical and practical basis, on how to analyze the lining wear.
Ames Lab 101: Next Generation Power Lines
Russell, Alan
2016-07-12
Ames Laboratory scientist Alan Russell discusses the need to develop new power lines that are stronger and more conductive as a way to address the problem of the nation's aging and inadequate power grid.
Northern Pass Transmission Line Project Environmental Impact...
Office of Environmental Management (EM)
persons who have subscribed to the email list of this change via email on September 10, ... Line Project (174.73 KB) More Documents & Publications EIS-0463: Notice of ...
On-line chemical composition analyzer development
Garrison, A.A.
1993-01-01
This report relates to the development of an on-line Raman analyzer for control of a distillation column. It is divided into: program issues, experimental control system evaluation, energy savings analysis, and reliability analysis. (DLC)
factsheet - trees and power lines - July 2008
U.S. Department of Energy (DOE) - all webpages (Extended Search)
Trees and power lines July 2008 This summer, BPA maintenance crews are inspecting and clearing high-growing vegetation from all 8,500- miles (15,000 circuit miles) of our...
Line Environment, Safety and Health Oversight
Directives, Delegations, and Other Requirements [Office of Management (MA)]
1997-06-26
Sets forth the Department's expectations line management environment, safety and health (ES&H) oversight and for the use of contractor self-assessment programs as the cornerstone for this oversight. Canceled by DOE O 226.1.
DNA Assembly Line for Nano-Construction
Oleg Gang
2010-01-08
Building on the idea of using DNA to link up nanoparticles scientists at Brookhaven National Lab have designed a molecular assembly line for high-precision nano-construction. Nanofabrication is essential for exploiting the unique properties of nanoparticl
Insulate Steam Distribution and Condensate Return Lines
This tip sheet on insulating steam distribution and condensate return lines provides how-to advice for improving industrial steam systems using low-cost, proven practices and technologies.
Dark matter line emission constraints from NuSTAR observations of the bullet cluster
Riemer-SĂ¸rensen, S.; Wik, D.; Madejski, G.; Molendi, S.; Gastaldello, F.; Harrison, F. A.; Craig, W. W.; Hailey, C. J.; Boggs, S. E.; Christensen, F. E.; Stern, D.; Zhang, W. W.; Hornstrup, A.
2015-08-27
Some dark matter candidates, e.g., sterile neutrinos, provide observable signatures in the form of mono-energetic line emission. Here, we present the first search for dark matter line emission in the $3-80\\;\\mathrm{keV}$ range in a pointed observation of the Bullet Cluster with NuSTAR. We do not detect any significant line emission and instead we derive upper limits (95% CL) on the flux, and interpret these constraints in the context of sterile neutrinos and more generic dark matter candidates. NuSTAR does not have the sensitivity to constrain the recently claimed line detection at $3.5\\;\\mathrm{keV}$, but improves on the constraints for energies of $10-25\\;\\mathrm{keV}$.
Dark matter line emission constraints from NuSTAR observations of the bullet cluster
Riemer-SĂ¸rensen, S.; Wik, D.; Madejski, G.; Molendi, S.; Gastaldello, F.; Harrison, F. A.; Craig, W. W.; Hailey, C. J.; Boggs, S. E.; Christensen, F. E.; et al
2015-08-27
Some dark matter candidates, e.g., sterile neutrinos, provide observable signatures in the form of mono-energetic line emission. Here, we present the first search for dark matter line emission in themoreÂ Â» $$3-80\\;\\mathrm{keV}$$ range in a pointed observation of the Bullet Cluster with NuSTAR. We do not detect any significant line emission and instead we derive upper limits (95% CL) on the flux, and interpret these constraints in the context of sterile neutrinos and more generic dark matter candidates. NuSTAR does not have the sensitivity to constrain the recently claimed line detection at $$3.5\\;\\mathrm{keV}$$, but improves on the constraints for energies of $$10-25\\;\\mathrm{keV}$$.Â«Â less
Design of the ILC RTML Extraction Lines
Seletskiy, S.; Tenenbaum, P.; Walz, D.; Solyak, N.; /Fermilab
2011-10-17
The ILC [1] Damping Ring to the Main Linac beamline (RTML) contains three extraction lines (EL). Each EL can be used both for an emergency abort dumping of the beam and tune-up continual train-by-train extraction. Two of the extraction lines are located downstream of the first and second stages of the RTML bunch compressor, and must accept both compressed and uncompressed beam with energy spreads of 2.5% and 0.15%, respectively. In this paper we report on an optics design that allowed minimizing the length of the extraction lines while offsetting the beam dumps from the main line by the distance required for acceptable radiation levels in the service tunnel. The proposed extraction lines can accommodate beams with different energy spreads while at the same time providing the beam size acceptable for the aluminum dump window. The RTML incorporates three extraction lines, which can be used for either an emergency beam abort or for a train-by-train extraction. The first EL is located downstream of the Damping Ring extraction arc. The other two extraction lines are located downstream of each stage of the two-stage bunch compressor. The first extraction line (EL1) receives 5GeV beam with an 0.15% energy spread. The extraction line located downstream of the first stage of bunch compressor (ELBC1) receives both compressed and uncompressed beam, and therefore must accept beam with both 5 and 4.88GeV energy, and 0.15% and 2.5% energy spread, respectively. The extraction line located after the second stage of the bunch compressor (ELBC2) receives 15GeV beam with either 0.15 or 1.8% energy spread. Each of the three extraction lines is equipped with the 220kW aluminum ball dump, which corresponds to the power of the continuously dumped beam with 5GeV energy, i.e., the beam trains must be delivered to the ELBC2 dump at reduced repetition rate.
LINE Commission Visits Idaho National Laboratory
U.S. Department of Energy (DOE) - all webpages (Extended Search)
LINE Commission Visits Idaho National Laboratory Members of the state of Idahoďż˝s Leadership in Nuclear Energy (LINE) Commission recently visited the Idaho National Laboratory and related DOE-Idaho cleanup facilities. These photos show commission members at the Materials and Fuels Complex, where Steve Marschman from INL talks to the commission members, and the Advanced Mixed Waste Treatment Facility. At the AMWTP, members saw the supercompactor as Facility Manager Jeremy Hampton explained how