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 Gravitational waves (5)
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Articles 1  30 of 50
FullText Articles in Physical Sciences and Mathematics
Rounding Of A FirstOrder Quantum Phase Transition To A StrongCoupling Critical Point, Fawaz Hrahsheh, Jose A. Hoyos, Thomas Vojta
Rounding Of A FirstOrder Quantum Phase Transition To A StrongCoupling Critical Point, Fawaz Hrahsheh, Jose A. Hoyos, Thomas Vojta
Physics Faculty Research & Creative Works
We investigate the effects of quenched disorder on firstorder quantum phase transitions on the example of the Ncolor quantum AshkinTeller model. By means of a strongdisorder renormalization group, we demonstrate that quenched disorder rounds the firstorder quantum phase transition to a continuous one for both weak and strong coupling between the colors. In the strongcoupling case, we find a distinct type of infiniterandomness critical point characterized by additional internal degrees of freedom. We investigate its critical properties in detail and find stronger thermodynamic singularities than in the random transverse field Ising chain. We also discuss the implications for higher spatial ...
Clustering Of Sloan Digital Sky Survey Iii Photometric Luminous Galaxies: The Measurement, Systematics, And Cosmological Implications, Shirley Ho, Antonio J. Cuesta, HeeJong Seo, Roland De Putter, Ashley J. Ross, Martin White, Nikhil Padmanabhan, Shun Saito, For Full List Of Authors, See Publisher's Website.
Clustering Of Sloan Digital Sky Survey Iii Photometric Luminous Galaxies: The Measurement, Systematics, And Cosmological Implications, Shirley Ho, Antonio J. Cuesta, HeeJong Seo, Roland De Putter, Ashley J. Ross, Martin White, Nikhil Padmanabhan, Shun Saito, For Full List Of Authors, See Publisher's Website.
Physics Faculty Research & Creative Works
The Sloan Digital Sky Survey (SDSS) surveyed 14,555 deg^{2}, and delivered over a trillion pixels of imaging data. We present a study of galaxy clustering using 900,000 luminous galaxies with photometric redshifts, spanning between z = 0.45 and z = 0.65, constructed from the SDSS using methods described in Ross et al. This data set spans 11,000 deg^{2} and probes a volume of 3 h^{3} Gpc^{3}, making it the largest volume ever used for galaxy clustering measurements. We describe in detail the construction of the survey window function and various systematics affecting our ...
Acoustic Scale From The Angular Power Spectra Of SdssIii Dr8 Photometric Luminous Galaxies, HeeJong Seo, Shirley Ho, Martin White, Antonio J. Cuesta, Ashley J. Ross, Shun Saito, For Full List Of Authors, See Publisher's Website.
Acoustic Scale From The Angular Power Spectra Of SdssIii Dr8 Photometric Luminous Galaxies, HeeJong Seo, Shirley Ho, Martin White, Antonio J. Cuesta, Ashley J. Ross, Shun Saito, For Full List Of Authors, See Publisher's Website.
Physics Faculty Research & Creative Works
We measure the acoustic scale from the angular power spectra of the Sloan Digital Sky Survey III (SDSSIII) Data Release 8 imaging catalog that includes 872, 921 galaxies over ~10,000 deg^{2} between 0.45 < z < 0.65. The extensive spectroscopic training set of the Baryon Oscillation Spectroscopic Survey luminous galaxies allows precise estimates of the true redshift distributions of galaxies in our imaging catalog. Utilizing the redshift distribution information, we build templates and fit to the power spectra of the data, which are measured in our companion paper, to derive the location of Baryon acoustic oscillations (BAOs) while marginalizing over many free parameters to exclude nearly all of the nonBAO signal. We derive the ratio of the angular diameter distance to the sound horizon scale D_{A}(z)/r_{s} = 9.212^{+0.416}_{0.404 } at z = 0.54, and therefore DA (z) = 1411 ± 65 Mpc at z = 0.54; the result is fairly independent of assumptions on the underlying cosmology. Our measurement of angular diameter distance D_{A}(z) is 1.4σ higher than what is expected for the concordance ΛCDM, in accordance to the trend of other ...
Disordered Bosons In One Dimension: From Weak To StrongRandomness Criticality, Fawaz Hrahsheh, Thomas Vojta
Disordered Bosons In One Dimension: From Weak To StrongRandomness Criticality, Fawaz Hrahsheh, Thomas Vojta
Physics Faculty Research & Creative Works
We investigate the superfluidinsulator quantum phase transition of onedimensional bosons with offdiagonal disorder by means of largescale Monte Carlo simulations. For weak disorder, we find the transition to be in the same universality class as the superfluidMott insulator transition of the clean system. The nature of the transition changes for stronger disorder. Beyond a critical disorder strength, we find nonuniversal, disorderdependent critical behavior. We compare our results to recent perturbative and strongdisorder renormalization group predictions. We also discuss experimental implications as well as extensions of our results to other systems.
LaserInduced Electron Diffraction For Probing Rare Gas Atoms, Junliang Xu, Cosmin I. Blaga, Anthony D. Dichiara, Emily Sistrunk, Kaikai Zhang, Zhangjin Chen, AnhThu Le, Toru Morishita, C. D. Lin, Pierre Agostini, Louis F. Dimauro
LaserInduced Electron Diffraction For Probing Rare Gas Atoms, Junliang Xu, Cosmin I. Blaga, Anthony D. Dichiara, Emily Sistrunk, Kaikai Zhang, Zhangjin Chen, AnhThu Le, Toru Morishita, C. D. Lin, Pierre Agostini, Louis F. Dimauro
Physics Faculty Research & Creative Works
Recently, using midinfrared laserinduced electron diffraction (LIED), snapshots of a vibrating diatomic molecule on a femtosecond time scale have been captured [C.I. Blaga et al., Nature (London) 483, 194 (2012)]. In this Letter, a comprehensive treatment for the atomic LIED response is reported, a critical step in generalizing this imaging method. Electronion differential cross sections (DCSs) of rare gas atoms are extracted from measured angularresolved, highenergy electron momentum distributions generated by intense midinfrared lasers. Following strongfield ionization, the highenergy electrons result from elastic rescattering of a fielddriven wave packet with the parent ion. For recollision energies [greater or equal ...
Theory Of High Harmonic Generation For Probing TimeResolved LargeAmplitude Molecular Vibrations With Ultrashort Intense Lasers, AnhThu Le, Toru Morishita, R. R. Lucchese, C. D. Lin
Theory Of High Harmonic Generation For Probing TimeResolved LargeAmplitude Molecular Vibrations With Ultrashort Intense Lasers, AnhThu Le, Toru Morishita, R. R. Lucchese, C. D. Lin
Physics Faculty Research & Creative Works
We present a theory that incorporates the vibrational degrees of freedom in a highorder harmonic generation (HHG) process with ultrashort intense laser pulses. In this model, laserinduced timedependent transition dipoles for each fixed molecular geometry are added coherently, weighted by the laserdriven timedependent nuclear wave packet distribution. We show that the nuclear distribution can be strongly modified by the HHG driving laser. The validity of this model is first checked against results from the numerical solution of the timedependent Schrödinger equation for a simple model system. We show that in combination with the established quantitative rescattering theory this model is ...
Swift FollowUp Observations Of Candidate GravitationalWave Transient Events, P. A. Evans, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.
Swift FollowUp Observations Of Candidate GravitationalWave Transient Events, P. A. Evans, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.
Physics Faculty Research & Creative Works
We present the first multiwavelength followup observations of two candidate gravitationalwave (GW) transient events recorded by LIGO and Virgo in their 20092010 science run. The events were selected with low latency by the network of GW detectors (within less than 10 minutes) and their candidate sky locations were observed by the Swift observatory (within 12 hr). Image transient detection was used to analyze the collected electromagnetic data, which were found to be consistent with background. Offline analysis of the GW data alone has also established that the selected GW events show no evidence of an astrophysical origin; one of them ...
Monte Carlo Simulations Of The Clean And Disordered Contact Process In Three Dimensions, Thomas Vojta
Monte Carlo Simulations Of The Clean And Disordered Contact Process In Three Dimensions, Thomas Vojta
Physics Faculty Research & Creative Works
The absorbingstate transition in the threedimensional contact process with and without quenched randomness is investigated by means of Monte Carlo simulations. In the clean case, a reweighting technique is combined with a careful extrapolation of the data to infinite time to determine with high accuracy the critical behavior in the threedimensional directed percolation universality class. In the presence of quenched spatial disorder, our data demonstrate that the absorbingstate transition is governed by an unconventional infiniterandomness critical point featuring activated dynamical scaling. The critical behavior of this transition does not depend on the disorder strength, i.e., it is universal. Close ...
Quantum Dynamics In AtomicFountain Experiments For Measuring The Electric Dipole Moment Of The Electron With Improved Sensitivity, Benedikt J. Wundt, Charles T. Munger, Ulrich D. Jentschura
Quantum Dynamics In AtomicFountain Experiments For Measuring The Electric Dipole Moment Of The Electron With Improved Sensitivity, Benedikt J. Wundt, Charles T. Munger, Ulrich D. Jentschura
Physics Faculty Research & Creative Works
An improved measurement of the electron electric dipole moment (EDM) appears feasible using groundstate alkali atoms in an atomic fountain in which a strong electric field, which couples to a conceivable EDM, is applied perpendicular to the fountain axis. In a practical fountain, the ratio of the atomic tensor Stark shift to the Zeeman shift is a factor μ ~ 100.We expand the complete timeevolution operator in inverse powers of this ratio; complete results are presented for atoms of total spin F = 3, 4, and 5. For a specific set of entangled hyperfine sublevels (coherent states), potential systematic errors enter ...
Random Fields At A Nonequilibrium Phase Transition, Hatem Barghathi, Thomas Vojta
Random Fields At A Nonequilibrium Phase Transition, Hatem Barghathi, Thomas Vojta
Physics Faculty Research & Creative Works
We study nonequilibrium phase transitions in the presence of disorder that locally breaks the symmetry between two equivalent macroscopic states. In lowdimensional equilibrium systems, such randomfield disorder is known to have dramatic effects: it prevents spontaneous symmetry breaking and completely destroys the phase transition. In contrast, we show that the phase transition of the onedimensional generalized contact process persists in the presence of randomfield disorder. The ultraslow dynamics in the symmetrybroken phase is described by a Sinai walk of the domain walls between two different absorbing states. We discuss the generality and limitations of our theory, and we illustrate our ...
Search For Gravitational Waves Associated With GammaRay Bursts During Ligo Science Run 6 And Virgo Science Runs 2 And 3, J. Abadie, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.
Search For Gravitational Waves Associated With GammaRay Bursts During Ligo Science Run 6 And Virgo Science Runs 2 And 3, J. Abadie, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.
Physics Faculty Research & Creative Works
We present the results of a search for gravitational waves associated with 154 gammaray bursts (GRBs) that were detected by satellitebased gammaray experiments in 20092010, during the sixth LIGO science run and the second and third Virgo science runs. We perform two distinct searches: a modeled search for coalescences of either two neutron stars or a neutron star and black hole, and a search for generic, unmodeled gravitationalwave bursts. We find no evidence for gravitationalwave counterparts, either with any individual GRB in this sample or with the population as a whole. For all GRBs we place lower bounds on the ...
Erratum: Search For Gravitational Waves From Binary Black Hole Inspiral, Merger, And Ringdown (Physical Review D  Particles, Fields, Gravitation And Cosmology (2011) 83 (122005)), J. Abadie, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.
Erratum: Search For Gravitational Waves From Binary Black Hole Inspiral, Merger, And Ringdown (Physical Review D  Particles, Fields, Gravitation And Cosmology (2011) 83 (122005)), J. Abadie, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.
Physics Faculty Research & Creative Works
Since the publication we have discovered two errors in the calculation of upper limits on binary black hole (BBH) coalescence rates inferred from the nondetection of gravitational waves. The errors caused systematic biases of opposite signs and different sizes in the 90% confidence rate limits; when errors are corrected, the resulting limits are a factor 3 to 5 smaller than those quoted. Here we give a brief description of the errors and report their impacts on the upper limit results.
NonFermi Liquid Transport And "Universal" Ratios In Quantum Griffiths Phases, David Nozadze, Thomas Vojta
NonFermi Liquid Transport And "Universal" Ratios In Quantum Griffiths Phases, David Nozadze, Thomas Vojta
Physics Faculty Research & Creative Works
We use the semiclassical Boltzmann equation to investigate transport properties such as electrical resistivity, thermal resistivity, thermopower, and the Peltier coefficient of disordered metals close to an antiferromagnetic quantum phase transition. In the quantum Griffiths phase, the electrons are scattered by spinfluctuations in the rare regions. This leads to singular temperature dependencies not just at the quantum critical point, but in the entire Griffiths phase. We show that the resulting nonuniversal powerlaws in transport properties are controlled by the same Griffiths exponent λ which governs the thermodynamics. λ takes the value zero at the quantum critical point and increases throughout ...
IonLithium Collision Dynamics Studied With A LaserCooled InRing Target, Daniel Fischer, Dominik Globig, Johannes Goullon, Manfred Grieser, Renate Hubele, Vitor L B D De Jesus, Aditya H. Kelkar, Aaron C. Laforge, H. Lindenblatt, Deepankar S. Misra, B. Najjari, Katharina R. Schneider, Michael Schulz, Martin Sell, Xincheng Wang
IonLithium Collision Dynamics Studied With A LaserCooled InRing Target, Daniel Fischer, Dominik Globig, Johannes Goullon, Manfred Grieser, Renate Hubele, Vitor L B D De Jesus, Aditya H. Kelkar, Aaron C. Laforge, H. Lindenblatt, Deepankar S. Misra, B. Najjari, Katharina R. Schneider, Michael Schulz, Martin Sell, Xincheng Wang
Physics Faculty Research & Creative Works
We present a novel experimental tool allowing for kinematically complete studies of breakup processes of lasercooled atoms. This apparatus, the 'MOTReMi,' is a combination of a magnetooptical trap (MOT) and a reaction microscope (ReMi). Operated in an ionstorage ring, the new setup enables us to study the dynamics in swift ionatom collisions on an unprecedented level of precision and detail. In the inaugural experiment on collisions with 1.5MeV/amu O8 ^{+}Li the pure ionization of the valence electron as well as the ionizationexcitation of the lithium target was investigated.
Erratum: Triple Compton Effect: A Photon Splitting Into Three Upon Collision With A Free Electron (Physical Review Letters (2012) 108 (233201)), Erik Loetstedt, Ulrich D. Jentschura
Erratum: Triple Compton Effect: A Photon Splitting Into Three Upon Collision With A Free Electron (Physical Review Letters (2012) 108 (233201)), Erik Loetstedt, Ulrich D. Jentschura
Physics Faculty Research & Creative Works
No abstract provided.
Quantum Electrodynamic Corrections To The G Factor Of Helium P States, Mariusz Puchalski, Ulrich D. Jentschura
Quantum Electrodynamic Corrections To The G Factor Of Helium P States, Mariusz Puchalski, Ulrich D. Jentschura
Physics Faculty Research & Creative Works
The Landég factor describes the response of an atomic energy level to an external perturbation by a uniform and constant magnetic field. In the case of manyelectron systems, the leading term is given by the interaction μ _{B}(L +2S )•B , where L and S are the orbital and spin angular momentum operators, respectively, summed over all electrons. For helium, a longstanding experimentaltheoretical discrepancy for P states motivates a reevaluation of the higher order terms which follow from relativistic quantum theory and quantum electrodynamics (QED). The tensor structure of relativistic corrections involves scalar, vector, and symmetric and antisymmetric tensor components ...
Percolation Transition In Quantum Ising And Rotor Models With SubOhmic Dissipation, Manal AlAli, Jose Abel Hoyos, Thomas Vojta
Percolation Transition In Quantum Ising And Rotor Models With SubOhmic Dissipation, Manal AlAli, Jose Abel Hoyos, Thomas Vojta
Physics Faculty Research & Creative Works
We investigate the influence of subOhmic dissipation on randomly diluted quantum Ising and rotor models. The dissipation causes the quantum dynamics of sufficiently large percolation clusters to freeze completely. As a result, the zerotemperature quantum phase transition across the lattice percolation threshold separates an unusual superparamagnetic cluster phase from an inhomogeneous ferromagnetic phase. We determine the lowtemperature thermodynamic behavior in both phases, which is dominated by large frozen and slowly fluctuating percolation clusters. We relate our results to the smeared transition scenario for disordered quantum phase transitions, and we compare the cases of subOhmic, Ohmic, and superOhmic dissipation.
ThreeBody Dynamics In Single Ionization Of Atomic Hydrogen By 75 Kev Proton Impact, Aaron Laforge, Kisra Egodapitiya, Sachin Sharma, Michael Schulz
ThreeBody Dynamics In Single Ionization Of Atomic Hydrogen By 75 Kev Proton Impact, Aaron Laforge, Kisra Egodapitiya, Sachin Sharma, Michael Schulz
Physics Faculty Research & Creative Works
We have measured and calculated doubly differential cross sections for ionization of atomic hydrogen using 75keV proton impact for fixed projectile energy losses as a function of scattering angle.
Projectile Coherence Effects In Electron Capture By Protons Colliding With H₂ And He, Sachin D. Sharma, Ahmad Hasan, Kisra N. Egodapitiya, T. P. Arthanayaka, G. Sakhelashvili, Michael Schulz
Projectile Coherence Effects In Electron Capture By Protons Colliding With H₂ And He, Sachin D. Sharma, Ahmad Hasan, Kisra N. Egodapitiya, T. P. Arthanayaka, G. Sakhelashvili, Michael Schulz
Physics Faculty Research & Creative Works
We have measured differential cross sections for single and dissociative capture for 25 and 75 keV protons colliding with H_{2} and He. Significant differences were found depending on whether the projectile beam was coherent or incoherent. For 75 keV p+H_{2} these differences can be mostly associated with molecular twocenter interference and possibly some contributions from path interference. For 25 keV (both targets) they are mostly due to path interference between different impact parameters leading to the same scattering angles and, for the H_{2} target, possibly some contributions from molecular twocenter interference.
CompositionDependent Oxygen Vacancy Formation In Multicomponent WideBandGap Oxides, Altynbek Murat, Julia E. Medvedeva
CompositionDependent Oxygen Vacancy Formation In Multicomponent WideBandGap Oxides, Altynbek Murat, Julia E. Medvedeva
Physics Faculty Research & Creative Works
The formation and distribution of oxygen vacancy in layered multicomponent InAMO _{4} oxides with A3 ^{+}=Al or Ga and M2 ^{+}=Ca or Zn and in the corresponding binary oxide constituents is investigated using firstprinciples density functional calculations. Comparing the calculated formation energies of the oxygen defect at six different site locations within the structurally and chemically distinct layers of InAMO _{4} oxides, we find that the vacancy distribution is significantly affected not only by the strength of the metaloxygen bonding, but also by the cation's ability to adjust to anisotropic oxygen environment created by the vacancy. In particular, the ...
Four Body Charge Transfer Process In Proton Helium Collision, Ujjal Chowdhury, Allison L. Harris, Jerry Peacher, Don H. Madison
Four Body Charge Transfer Process In Proton Helium Collision, Ujjal Chowdhury, Allison L. Harris, Jerry Peacher, Don H. Madison
Physics Faculty Research & Creative Works
Recent advancements in experimental techniques now allow for the study of fully differential cross sections for 4body collisions. Theoretical fully differential cross sections will be presented and compared with absolute experimental data for transferexcitation in protonhelium collisions. The role of different scattering mechanism will be discussed.
Implications For The Origin Of Grb 051103 From Ligo Observations, J. Abadie, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.
Implications For The Origin Of Grb 051103 From Ligo Observations, J. Abadie, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.
Physics Faculty Research & Creative Works
We present the results of a LIGO search for gravitational waves (GWs) associated with GRB 051103, a shortduration hardspectrum gammaray burst (GRB) whose electromagnetically determined sky position is coincident with the spiral galaxy M81, which is 3.6 Mpc from Earth. Possible progenitors for shorthard GRBs include compact object mergers and soft gamma repeater (SGR) giant flares. A merger progenitor would produce a characteristic GW signal that should be detectable at a distance of M81, while GW emission from an SGR is not expected to be detectable at that distance. We found no evidence of a GW signal associated with ...
Low Energy (E, 2e) Study From The 1t₂ Orbital Of Ch₄, Shenyue Xu, Hari Chaluvadi, Xueguang Ren, Thomas Pfluger, Arne Senftleben, Chuangang Ning, Shuncheng Yan, Peng Zhang, Jie Yang, Xinwen Ma, Joachim Hermann Ullrich, Don H. Madison, Alexander Dorn
Low Energy (E, 2e) Study From The 1t₂ Orbital Of Ch₄, Shenyue Xu, Hari Chaluvadi, Xueguang Ren, Thomas Pfluger, Arne Senftleben, Chuangang Ning, Shuncheng Yan, Peng Zhang, Jie Yang, Xinwen Ma, Joachim Hermann Ullrich, Don H. Madison, Alexander Dorn
Physics Faculty Research & Creative Works
Single ionization of the methane (CH_{4}) 1t_{2} orbital by 54 eV electron impact has been studied experimentally and theoretically. The measured triple differential cross sections cover nearly a 4π solid angle for the emission of low energy electrons and a range of projectile scattering angles. Experimental data are compared with theoretical calculations from the distorted wave Born approximation and the molecular threebody distorted wave models. It is found that theory can give a proper description of the main features of experimental cross section only at smaller scattering angles. For larger scattering angles, significant discrepancies between experiment and theory ...
Conditions For Extracting Photoionization Cross Sections From LaserInduced HighOrderHarmonic Spectra, Guoli Wang, Cheng Jin, AnhThu Le, C. D. Lin
Conditions For Extracting Photoionization Cross Sections From LaserInduced HighOrderHarmonic Spectra, Guoli Wang, Cheng Jin, AnhThu Le, C. D. Lin
Physics Faculty Research & Creative Works
We show that photoionization cross sections of atoms can be accurately extracted from the highorderharmonic spectra generated by intense infrared lasers only if the degree of ionization in the gas medium is small, implying that for this purpose the highorderharmonic generation spectra should be taken at low gas pressure and at low laser intensity experimentally.
Fully Differential Cross Section For Four Body Charge Transfer Process, Ujjal Chowdhury, Allison L. Harris, Jerry Peacher, Don H. Madison
Fully Differential Cross Section For Four Body Charge Transfer Process, Ujjal Chowdhury, Allison L. Harris, Jerry Peacher, Don H. Madison
Physics Faculty Research & Creative Works
Recently experimental fully differential cross sections (FDCS) have been reported for double capture in proton helium collisions which disagree with existing theoretical calculations by two orders of magnitude. We introduce here a theoretical model for charge transfer processes which is fully quantum mechanical and takes all post collision interactions (PCI) between the particles into account exactly. The results of this model are in much better agreement with experimental data.
AllSky Search For GravitationalWave Bursts In The Second Joint LigoVirgo Run, J. Abadie, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.
AllSky Search For GravitationalWave Bursts In The Second Joint LigoVirgo Run, J. Abadie, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.
Physics Faculty Research & Creative Works
We present results from a search for gravitationalwave bursts in the data collected by the LIGO and Virgo detectors between July 7, 2009 and October 20, 2010: data are analyzed when at least two of the three LIGOVirgo detectors are in coincident operation, with a total observation time of 207 days. The analysis searches for transients of duration ≲ 1 s over the frequency band 645000 Hz, without other assumptions on the signal waveform, polarization, direction or occurrence time. All identified events are consistent with the expected accidental background. We set frequentist upper limits on the rate of gravitationalwave bursts by ...
Triple Compton Effect: A Photon Splitting Into Three Upon Collision With A Free Electron, Erik Loetstedt, Ulrich D. Jentschura
Triple Compton Effect: A Photon Splitting Into Three Upon Collision With A Free Electron, Erik Loetstedt, Ulrich D. Jentschura
Physics Faculty Research & Creative Works
The process in which a photon splits into three after the collision with a free electron (triple Compton effect) is the most basic process for the generation of a highenergy multiparticle entangled state composed out of elementary quanta. The cross section of the process is evaluated in two experimentally realizable situations, one employing gamma photons and stationary electrons, and the other using keV photons and GeV electrons of an xray free electron laser. For the first case, our calculation is in agreement with the only available measurement of the differential cross section for the process under study. Our estimates indicate ...
Upper Limits On A Stochastic GravitationalWave Background Using Ligo And Virgo Interferometers At 6001000 Hz, J. Abadie, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.
Upper Limits On A Stochastic GravitationalWave Background Using Ligo And Virgo Interferometers At 6001000 Hz, J. Abadie, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.
Physics Faculty Research & Creative Works
A stochastic background of gravitational waves is expected to arise from a superposition of many incoherent sources of gravitational waves, of either cosmological or astrophysical origin. This background is a target for the current generation of groundbased detectors. In this article we present the first joint search for a stochastic background using data from the LIGO and Virgo interferometers. In a frequency band of 6001000 Hz, we obtained a 95% upper limit on the amplitude of Ω_{GW}(f) = Ω_{3}(f/900Hz)^{3}, of Ω_{3} < 0.32, assuming a value of the Hubble parameter of h_{100} = 0.71. These new limits are a factor of seven better than ...
Dissipation Effects In Random TransverseField Ising Chains, Jose A. Hoyos, Thomas Vojta
Dissipation Effects In Random TransverseField Ising Chains, Jose A. Hoyos, Thomas Vojta
Physics Faculty Research & Creative Works
We study the effects of Ohmic, superOhmic, and subOhmic dissipation on the zerotemperature quantum phase transition in the random transversefield Ising chain by means of an (asymptotically exact) analytical strongdisorder renormalizationgroup approach. We find that Ohmic damping destabilizes the infiniterandomness critical point and the associated quantum Griffiths singularities of the dissipationless system. The quantum dynamics of large magnetic clusters freezes completely, which destroys the sharp phase transition by smearing. The effects of subOhmic dissipation are similar and also lead to a smeared transition. In contrast, superOhmic damping is an irrelevant perturbation; the critical behavior is thus identical to that of ...
First LowLatency Ligo+Virgo Search For Binary Inspirals And Their Electromagnetic Counterparts, J. Abadie, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.
First LowLatency Ligo+Virgo Search For Binary Inspirals And Their Electromagnetic Counterparts, J. Abadie, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.
Physics Faculty Research & Creative Works
Aims. The detection and measurement of gravitationalwaves from coalescing neutronstar binary systems is an important science goal for groundbased gravitationalwave detectors. In addition to emitting gravitationalwaves at frequencies that span the most sensitive bands of the LIGO and Virgo detectors, these sources are also amongst the most likely to produce an electromagnetic counterpart to the gravitationalwave emission. A joint detection of the gravitationalwave and electromagnetic signals would provide a powerful new probe for astronomy. Methods. During the period between September 19 and October 20, 2010, the first lowlatency search for gravitationalwaves from binary inspirals in LIGO and Virgo data was ...