Open Access. Powered by Scholars. Published by Universities.®
- Discipline
- Keyword
-
- Condensed matter (8)
- Soft condensed matter (5)
- Cell behavior (2)
- Plasmonics (2)
- Superconductivity (2)
-
- Biological physics (1)
- Coalescence (1)
- Drop coalescence (1)
- Drops (1)
- Electrical methods (1)
- Flow geometries (1)
- High speed imaging (1)
- Inertial effect (1)
- Length scale (1)
- Light-trapping (1)
- Liquid drop (1)
- Liquid viscosity (1)
- Liquids (1)
- Nanotechnology (1)
- Optofluidic (1)
- Photovoltaic (1)
- Qualitative methods (1)
- Self-assembly (1)
- Solar Energy (1)
- Solar cells (1)
- Statistical mechanics (1)
- Subcellular processes (1)
- Surfactant micelle (1)
Articles 31 - 60 of 72
Full-Text Articles in Physics
Rectification Of Vortex Motion In A Circular Ratchet Channel, Britton Plourde, N. S. Lin, T. W. Heitmann, Kang Yu, V. R. Misko
Rectification Of Vortex Motion In A Circular Ratchet Channel, Britton Plourde, N. S. Lin, T. W. Heitmann, Kang Yu, V. R. Misko
Physics - All Scholarship
We study the dynamics of vortices in an asymmetric ring channel driven by an external current I in a Corbino setup. The asymmetric potential can rectify the motion of vortices and cause a net flow without any unbiased external drive, which is called ratchet effect. With an applied ac current, the potential can rectify the motion of vortices in the channel and induce a dc net flow. We show that the net flow of vortices strongly depends on vortex density and frequency of the driving current. Depending on the density, we distinguish a "single-vortex" rectification regime (low density) determined by …
Active Jamming: Self-Propelled Soft Particles At High Density, Silke Henkes, Yaouen Fily, M. Christina Marchetti
Active Jamming: Self-Propelled Soft Particles At High Density, Silke Henkes, Yaouen Fily, M. Christina Marchetti
Physics - All Scholarship
We study numerically the phases and dynamics of a dense collection of self-propelled particles with soft repulsive interactions in two dimensions. The model is motivated by recent in vitro experiments on confluent monolayers of migratory epithelial and endothelial cells. The phase diagram exhibits a liquid phase with giant number fluctuations at low packing fraction and high self-propulsion speed and a jammed phase at high packing fraction and low self-propulsion speed. The dynamics of the jammed phase is controlled by the low frequency modes of the jammed packing.
Measurement Of The Inclusive Φ Cross-Section In Pp Collisions At √S = 7 Tev, Raymond Mountain, Marina Artuso, S. Blusk, Alessandra Borgia
Measurement Of The Inclusive Φ Cross-Section In Pp Collisions At √S = 7 Tev, Raymond Mountain, Marina Artuso, S. Blusk, Alessandra Borgia
Physics - All Scholarship
The cross-section for inclusive phi meson production in pp collisions at a centre-of-mass energy of sqrt(s) = 7 TeV has been measured with the LHCb detector at the Large Hadron Collider. The differential cross-section is measured as a function of the phi transverse momentum p_T and rapidity y in the region 0.6 < p_T < 5.0 GeV/c and 2.44 < y < 4.06. The cross-section for inclusive phi production in this kinematic range is sigma(pp -> phi X) = 1758 pm 19(stat) ^{+43}_{-14}(syst) pm 182(scale) microbarn, where the first systematic uncertainty depends on the p_T and y region and the second is related to the overall scale. Predictions based on the Pythia 6.4 generator underestimate the cross-section.
Measurement Of The Inclusive Phi Cross-Section In Pp Collisions At Sqrt(S) = 7 Tev, Raymond Mountain, Marina Artuso, S. Blusk, Alessandra Borgia
Measurement Of The Inclusive Phi Cross-Section In Pp Collisions At Sqrt(S) = 7 Tev, Raymond Mountain, Marina Artuso, S. Blusk, Alessandra Borgia
Physics - All Scholarship
The cross-section for inclusive phi meson production in pp collisions at a centre-of-mass energy of sqrt(s) = 7 TeV has been measured with the LHCb detector at the Large Hadron Collider. The differential cross-section is measured as a function of the phi transverse momentum p_T and rapidity y in the region 0.6 < p_T < 5.0 GeV/c and 2.44 < y < 4.06. The cross-section for inclusive phi production in this kinematic range is sigma(pp -> phi X) = 1758 pm 19(stat) ^{+43}_{-14}(syst) pm 182(scale) microbarn, where the first systematic uncertainty depends on the p_T and y region and the second is related to the overall scale. Predictions based on the Pythia 6.4 generator underestimate the cross-section.
Nonlinear Hydrodynamics Of Disentangled Flux-Line Liquids, Panayotis Benetatos, M. Cristina Marchetti
Nonlinear Hydrodynamics Of Disentangled Flux-Line Liquids, Panayotis Benetatos, M. Cristina Marchetti
Physics - All Scholarship
In this paper we use non-Gaussian hydrodynamics to study the magnetic response of a flux-line liquid in the mixed state of a type-II superconductor. Both the derivation of our model, which goes beyond conventional Gaussian flux liquid hydrodynamics, and its relationship to other approaches used in the literature are discussed. We focus on the response to a transverse tilting field which is controlled by the tilt modulus, c44, of the flux array. We show that interaction effects can enhance c44 even in infinitely thick clean materials. This enhancement can be interpreted as the appearance of a disentangled flux-liquid fraction. In …
Measurement Of V0 Production Ratios In Pp Collisions At √S= 0.9 And 7 Tev, Raymond Mountain, Marina Artuso, S. Blusk, Alessandra Borgia
Measurement Of V0 Production Ratios In Pp Collisions At √S= 0.9 And 7 Tev, Raymond Mountain, Marina Artuso, S. Blusk, Alessandra Borgia
Physics - All Scholarship
The \bar{\Lambda} / \Lambda and \bar{\Lambda} / K^0_\mathrm{S} production ratios are measured by the LHCb detector from 0.3\,\mathrm{nb}^{-1} of pp collisions delivered by the LHC at \sqrt{s} = 0.9\,TeV and 1.8\,\mathrm{nb}^{-1} at \sqrt{s} = 7\,TeV. Both ratios are presented as a function of transverse momentum, p_\mathrm{T}, and rapidity, y, in the ranges {0.15 < p_\mathrm{T} < 2.50\,\mathrm{GeV}/c} and {2.0}.
Measurement Of Measurement Of V 0 Production Ratios In Pp Collisions At Ps = 0.9 And 7tev, Raymond Mountain, Marina Artuso, S. Blusk, Alessandra Borgia
Measurement Of Measurement Of V 0 Production Ratios In Pp Collisions At Ps = 0.9 And 7tev, Raymond Mountain, Marina Artuso, S. Blusk, Alessandra Borgia
Physics - All Scholarship
The \bar{\Lambda} / \Lambda and \bar{\Lambda} / K^0_\mathrm{S} production ratios are measured by the LHCb detector from 0.3\,\mathrm{nb}^{-1} of pp collisions delivered by the LHC at \sqrt{s} = 0.9\,TeV and 1.8\,\mathrm{nb}^{-1} at \sqrt{s} = 7\,TeV. Both ratios are presented as a function of transverse momentum, p_\mathrm{T}, and rapidity, y, in the ranges {0.15 < p_\mathrm{T} < 2.50\,\mathrm{GeV}/c} and {2.0}
Theory Of Double-Sided Flux Decorations, M. Cristina Marchetti, David R. Nelson
Theory Of Double-Sided Flux Decorations, M. Cristina Marchetti, David R. Nelson
Physics - All Scholarship
A novel two-sided Bitter decoration technique was recently employed by Yao et al. to study the structure of the magnetic vortex array in high-temperature superconductors. Here we discuss the analysis of such experiments. We show that two-sided decorations can be used to infer {\it quantitative} information about the bulk properties of flux arrays, and discuss how a least squares analysis of the local density differences can be used to bring the two sides into registry. Information about the tilt, compressional and shear moduli of bulk vortex configurations can be extracted from these measurements.
Cooperative Self-Propulsion Of Active And Passive Rotors, Yaouen Fily, Aparna Baskaran, M. Cristina Marchetti
Cooperative Self-Propulsion Of Active And Passive Rotors, Yaouen Fily, Aparna Baskaran, M. Cristina Marchetti
Physics - All Scholarship
Using minimal models for low Reynolds number passive and active rotors in a fluid, we characterize the hydrodynamic interactions among rotors and the resulting dynamics of a pair of interacting rotors. This allows us to treat in a common framework passive or externally driven rotors, such as magnetic colloids driven by a rotating magnetic field, and active or internally driven rotors, such as sperm cells confined at boundaries. The hydrodynamic interaction of passive rotors contains an azimuthal component 1/r2 to dipolar order that can yield the recently discovered “cooperative self-propulsion” of a pair of rotors of opposite vorticity. While this …
Self-Propulsion Of Droplets By Spatially-Varying Roughness, Mark Bowick, Zhenwei Yao
Self-Propulsion Of Droplets By Spatially-Varying Roughness, Mark Bowick, Zhenwei Yao
Physics - All Scholarship
Under partial wetting conditions, making a substrate uniformly rougher enhances the wetting characteristics of the corresponding smooth substrate {--} hydrophilic systems become even more hydrophilic and hydrophobic systems even more hydrophobic. Here we show that spatial texturing of the roughness may lead to spontaneous propulsion of droplets. Individual droplets are driven toward regions of maximal roughness for intrinsically hydrophilic systems and toward regions of minimal roughness for intrinsically hydrophobic systems. Spatial texturing can be achieved by wrinkling the substrate with sinusoidal grooves whose wavelength varies in one direction (inhomogeneous wrinkling) or lithographically etching a radial pattern of fractal (Koch curve) …
Measurement Of The Eta_B(1s) Mass And The Branching Fraction For Upsilon(3s) --> Gamma Eta_B(1s), Raymond Mountain, Marina Artuso, S. Blusk, Sadia Khalil
Measurement Of The Eta_B(1s) Mass And The Branching Fraction For Upsilon(3s) --> Gamma Eta_B(1s), Raymond Mountain, Marina Artuso, S. Blusk, Sadia Khalil
Physics - All Scholarship
We report evidence for the ground state of bottomonium, eta_b(1S), in the radiative decay Upsilon(3S) --> gamma eta_b in e^+e^- annihilation data taken with the CLEO III detector. Using 6 million Upsilon(3S) decays, and assuming Gamma(eta_b) = 10 MeV/c^2, we obtain B(Upsilon(3S) --> gamma eta_b) = (7.1 +- 1.8 +- 1.1) X 10^{-4}, where the first error is statistical and the second is systematic. The statistical significance is about 4 sigma. The mass is determined to be M(eta_b) = 9391.8 +- 6.6 +- 2.0 MeV/c^2, which corresponds to the hyperfine splitting Delta M_{hf}(1S)_b = 68.5 +- 6.6 +- 2.0 MeV/c^2. …
Study Of Radiation Damage In Lead Tungstate Crystals Using Intense High Energy Beams, Raymond Mountain, K. Khroustalev, V.A. Batarin, T. Brennan
Study Of Radiation Damage In Lead Tungstate Crystals Using Intense High Energy Beams, Raymond Mountain, K. Khroustalev, V.A. Batarin, T. Brennan
Physics - All Scholarship
We report on the effects of radiation on the light output of lead tungstate crystals. The crystals were irradiated by pure, intense high energy electron and hadron beams as well as by a mixture of hadrons, neutrons and gammas. The crystals were manufactured in Bogoroditsk, Apatity (both Russia), and Shanghai (China). These studies were carried out at the 70-GeV proton accelerator in Protvino.
Chiral Nonet Mixing In Pi Pi Scattering, Joseph Schechter, Amir H. Fariborz, Renata Jora, M. Naeem Shahid
Chiral Nonet Mixing In Pi Pi Scattering, Joseph Schechter, Amir H. Fariborz, Renata Jora, M. Naeem Shahid
Physics - All Scholarship
Pion pion scattering is studied in a generalized linear sigma model which contains two scalar nonets (one of quark-antiquark type and the other of diquark-antidiquark type) and two corresponding pseudoscalar nonets. An interesting feature concerns the mixing of the four isosinglet scalar mesons which yield poles in the scattering amplitude. Some realism is introduced by enforcing exact unitarity via the K-matrix method. It is shown that a reasonable agreement with experimental data is obtained up to about 1 GeV. The poles in the unitarized scattering amplitude are studied in some detail. The lowest pole clearly represents the sigma meson (or …
Determination Of Fs/Fd For 7 Tev Pp Collisions And A Measurement Of The Branching Fraction Of The Decay B0→D-K+, Raymond Mountain, Marina Artuso, S. Blusk, S. Stone
Determination Of Fs/Fd For 7 Tev Pp Collisions And A Measurement Of The Branching Fraction Of The Decay B0→D-K+, Raymond Mountain, Marina Artuso, S. Blusk, S. Stone
Physics - All Scholarship
The relative abundance of the three decay modes B_d \to D^- K^+, B_d \to D^- \pi^+ and B_s \to D_s^- \pi^+ produced in 7 TeV pp collisions at the LHC is determined from data corresponding to an integrated luminosity of 35 pb^{-1}. The branching fraction of B_d \to D^- K^+ is found to be \cal B (B_d \to D^- K^+) = (2.01 \pm 0.18^{\textrm{stat}} \pm 0.14^{\textrm{syst}})\times 10^{-4}. The ratio of fragmentation fractions \fsfdt is determined through the relative abundance of B_s \to D_s^- \pi^+ to B_d \to D^- K^+ and B_d \to D^-\pi^+, leading to f_s/f_d = 0.253 \pm 0.017 …
Zero And Low Temperature Behavior Of The Two-Dimensional \Pm J Ising Spin Glass, Alan Middleton, Creighton K. Thomas, David A. Huse
Zero And Low Temperature Behavior Of The Two-Dimensional \Pm J Ising Spin Glass, Alan Middleton, Creighton K. Thomas, David A. Huse
Physics - All Scholarship
Scaling arguments and precise simulations are used to study the square lattice $\pm J$ Ising spin glass, a prototypical model for glassy systems. Droplet theory predicts, and our numerical results show, entropically-stabilized long range spin glass order at zero temperature. The low temperature scaling behavior has an important new crossover length scale that produces a power-law dependence of the heat capacity on temperature.
Determination Of F_S/F_D For 7 Tev Pp Collisions And A Measurement Of The Branching Fraction Of The Decay Bd->D-K+, Raymond Mountain, Marina Artuso, S. Blusk, Alessandra Borgia
Determination Of F_S/F_D For 7 Tev Pp Collisions And A Measurement Of The Branching Fraction Of The Decay Bd->D-K+, Raymond Mountain, Marina Artuso, S. Blusk, Alessandra Borgia
Physics - All Scholarship
The relative abundance of the three decay modes B_d \to D^- K^+, B_d \to D^- \pi^+ and B_s \to D_s^- \pi^+ produced in 7 TeV pp collisions at the LHC is determined from data corresponding to an integrated luminosity of 35 pb^{-1}. The branching fraction of B_d \to D^- K^+ is found to be \cal B (B_d \to D^- K^+) = (2.01 \pm 0.18^{\textrm{stat}} \pm 0.14^{\textrm{syst}})\times 10^{-4}. The ratio of fragmentation fractions \fsfdt is determined through the relative abundance of B_s \to D_s^- \pi^+ to B_d \to D^- K^+ and B_d \to D^-\pi^+, leading to f_s/f_d = 0.253 \pm 0.017 …
Analysis Of The Decay D^0 To K^0_S Pi^0 Pi^0, Raymond Mountain, Marina Artuso, S. Blusk, T. Skwarnicki
Analysis Of The Decay D^0 To K^0_S Pi^0 Pi^0, Raymond Mountain, Marina Artuso, S. Blusk, T. Skwarnicki
Physics - All Scholarship
We present the results of a Dalitz plot analysis of D^0 to K^0_S pi^0 pi^0 using the CLEO-c data set of 818 inverse pico-barns of e^+ e^- collisions accumulated at sqrt{s} = 3.77 GeV. This corresponds to three million D^0 D^0-bar pairs from which we select 1,259 tagged candidates with a background of 7.5 +- 0.9 percent. Several models have been explored, all of which include the K^*(892), K^*_2(1430), K^*(1680), the f_0(980), and the sigma(500). We find that the combined pi^0 pi^0 S-wave contribution to our preferred fit is (28.9 +- 6.3 +- 3.1)% of the total decay rate while …
Analysis Of The Decay D0 → K0sπ0Π0, Raymond Mountain, Marina Artuso, S. Blusk, T. Skwarnicki
Analysis Of The Decay D0 → K0sπ0Π0, Raymond Mountain, Marina Artuso, S. Blusk, T. Skwarnicki
Physics - All Scholarship
We present the results of a Dalitz plot analysis of D^0 to K^0_S pi^0 pi^0 using the CLEO-c data set of 818 inverse pico-barns of e^+ e^- collisions accumulated at sqrt{s} = 3.77 GeV. This corresponds to three million D^0 D^0-bar pairs from which we select 1,259 tagged candidates with a background of 7.5 +- 0.9 percent. Several models have been explored, all of which include the K^*(892), K^*_2(1430), K^*(1680), the f_0(980), and the sigma(500). We find that the combined pi^0 pi^0 S-wave contribution to our preferred fit is (28.9 +- 6.3 +- 3.1)% of the total decay rate while …
Motor-Driven Dynamics Of Cytoskeletal Filaments In Motility Assays, Shiladitya Banerjee, M. Cristina Marchetti, Kristian Muller-Nedebock
Motor-Driven Dynamics Of Cytoskeletal Filaments In Motility Assays, Shiladitya Banerjee, M. Cristina Marchetti, Kristian Muller-Nedebock
Physics - All Scholarship
We model analytically the dynamics of a cytoskeletal filament in a motility assay. The filament is described as rigid rod free to slide in two dimensions. The motor proteins consist of polymeric tails tethered to the plane and modeled as linear springs and motor heads that bind to the filament. As in related models of rigid and soft two-state motors, the binding/unbinding dynamics of the motor heads and the dependence of the transition rates on the load exerted by the motor tails play a crucial role in controlling the filament's dynamics. Our work shows that the filament effectively behaves as …
Polar Patterns In Active Fluids, Luca Giomi, M. Cristina Marchetti
Polar Patterns In Active Fluids, Luca Giomi, M. Cristina Marchetti
Physics - All Scholarship
We study the spatio-temporal dynamics of a model of polar active fluid in two dimensions. The system exhibits a transition from an isotropic to a polarized state as a function of density. The uniform polarized state is, however, unstable above a critical value of activity. Upon increasing activity, the active fluids displays increasingly complex patterns, including traveling bands, traveling vortices and chaotic behavior. The advection arising from the particles self-propulsion and unique to polar fluids yields qualitatively new behavior as compared to that obtain in active nematic, yielding traveling-wave structures. We show that the nonlinear hydrodynamic equations can be mapped …
Studies Of D+→ {Η', Η, Φ}E+Νe, Raymond Mountain, Marina Artuso, S. Blusk, T. Skwarnicki
Studies Of D+→ {Η', Η, Φ}E+Νe, Raymond Mountain, Marina Artuso, S. Blusk, T. Skwarnicki
Physics - All Scholarship
No abstract provided.
Measurement Of J/Ψ Production In Pp Collisions At √S=7 Tev, Raymond Mountain, Marina Artuso, S. Blusk, Alessandra Borgia
Measurement Of J/Ψ Production In Pp Collisions At √S=7 Tev, Raymond Mountain, Marina Artuso, S. Blusk, Alessandra Borgia
Physics - All Scholarship
The production of J/psi mesons in proton-proton collisions at sqrt(s)=7 TeV is studied with the LHCb detector at the LHC. The differential cross-section for prompt J/psi production is measured as a function of the J/psi transverse momentum pT and rapidity y in the fiducial region 0.
Measurement Of J/Psi Production In Pp Collisions At Sqrt(S)=7 Tev, Raymond Mountain, Marina Artuso, S. Blusk, Alessandra Borgia
Measurement Of J/Psi Production In Pp Collisions At Sqrt(S)=7 Tev, Raymond Mountain, Marina Artuso, S. Blusk, Alessandra Borgia
Physics - All Scholarship
The production of J/psi mesons in proton-proton collisions at sqrt(s)=7 TeV is studied with the LHCb detector at the LHC. The differential cross-section for prompt J/psi production is measured as a function of the J/psi transverse momentum pT and rapidity y in the fiducial region 0
Search For The Decay D+S→Ωe+Ν, Raymond Mountain, Marina Artuso, T. Skwarnicki
Search For The Decay D+S→Ωe+Ν, Raymond Mountain, Marina Artuso, T. Skwarnicki
Physics - All Scholarship
We present the first search for the decay D^+_{s}\to \omega e^{+}\nu to test the four-quark content of the D^+_{s} and the \omega-\phi mixing model for this decay. We use 586 \mathrm{pb}^{-1} of e^{+}e^{-} collision data collected at a center-of-mass energy of 4170 MeV. We find no evidence of a signal, and set an upper limit on the branching fraction of \mathcal{B}(D^+_{s}\to\omega e^+\nu)
Search For The Decay D^+_{S}\Toωe^+Ν, Raymond Mountain, Marina Artuso, S. Blusk, T. Skwarnicki
Search For The Decay D^+_{S}\Toωe^+Ν, Raymond Mountain, Marina Artuso, S. Blusk, T. Skwarnicki
Physics - All Scholarship
We present the first search for the decay D^+_{s}\to \omega e^{+}\nu to test the four-quark content of the D^+_{s} and the \omega-\phi mixing model for this decay. We use 586 \mathrm{pb}^{-1} of e^{+}e^{-} collision data collected at a center-of-mass energy of 4170 MeV. We find no evidence of a signal, and set an upper limit on the branching fraction of \mathcal{B}(D^+_{s}\to\omega e^+\nu)
First Observation Of B0s → Ds2*+ Xη-Ν Decays, Raymond Mountain, Marina Artuso, S. Blusk, Alessandra Borgia
First Observation Of B0s → Ds2*+ Xη-Ν Decays, Raymond Mountain, Marina Artuso, S. Blusk, Alessandra Borgia
Physics - All Scholarship
Using data collected with the LHCb detector in proton-proton collisions at a centre-of-mass energy of 7 TeV, the semileptonic decays Bs -> Ds+ X mu nu and Bs -> D0 K+ X mu nu are detected. Two structures are observed in the D0 K+ mass spectrum at masses consistent with the known D^+_{s1}(2536) and D^{*+}_{s2}(2573) mesons. The measured branching fractions relative to the total Bs semileptonic rate are B(Bs -> D_{s2}^{*+} X mu nu)/B(Bs -> X mu nu)= (3.3\pm 1.0\pm 0.4)%, and B(Bs -> D_{s1}^+ X munu)/B(Bs -> X mu nu)= (5.4\pm 1.2\pm 0.5)%, where the first uncertainty is statistical …
Observation Of The Dalitz Decay Ds*+ → Ds*+ E+E-, Raymond Mountain, Marina Artuso, T. Skwarnicki, S. Stone
Observation Of The Dalitz Decay Ds*+ → Ds*+ E+E-, Raymond Mountain, Marina Artuso, T. Skwarnicki, S. Stone
Physics - All Scholarship
Using 586 \textrm{pb}^{-1} of e^{+}e^{-} collision data acquired at \sqrt{s}=4.170 GeV with the CLEO-c detector at the Cornell Electron Storage Ring, we report the first observation of D_{s}^{*+} \to D_{s}^{+} e^{+} e^{-} with a significance of 5.3 \sigma. The ratio of branching fractions \calB(D_{s}^{*+} \to D_{s}^{+} e^{+} e^{-}) / \calB(D_{s}^{*+} \to D_{s}^{+} \gamma) is measured to be [ 0.72^{+0.15}_{-0.13} (\textrm{stat}) \pm 0.10 (\textrm{syst})]%, which is consistent with theoretical expectations.
Observation Of The Dalitz Decay D_{S}^{*+} \To D_{S}^{+} E^{+} E^{-}, Raymond Mountain, Marina Artuso, S. Blusk, T. Skwarnicki
Observation Of The Dalitz Decay D_{S}^{*+} \To D_{S}^{+} E^{+} E^{-}, Raymond Mountain, Marina Artuso, S. Blusk, T. Skwarnicki
Physics - All Scholarship
Using 586 \textrm{pb}^{-1} of e^{+}e^{-} collision data acquired at \sqrt{s}=4.170 GeV with the CLEO-c detector at the Cornell Electron Storage Ring, we report the first observation of D_{s}^{*+} \to D_{s}^{+} e^{+} e^{-} with a significance of 5.3 \sigma. The ratio of branching fractions \calB(D_{s}^{*+} \to D_{s}^{+} e^{+} e^{-}) / \calB(D_{s}^{*+} \to D_{s}^{+} \gamma) is measured to be [ 0.72^{+0.15}_{-0.13} (\textrm{stat}) \pm 0.10 (\textrm{syst})]%, which is consistent with theoretical expectations.
Beating The Spin-Down Limit On Gravitational Wave Emission From The Vela Pulsar, Duncan Brown, J. Abadie, Collin Capano, J. A. Garofoli, A. P. Lundgren
Beating The Spin-Down Limit On Gravitational Wave Emission From The Vela Pulsar, Duncan Brown, J. Abadie, Collin Capano, J. A. Garofoli, A. P. Lundgren
Physics - All Scholarship
We present direct upper limits on continuous gravitational wave emission from the Vela pulsar using data from the Virgo detector's second science run. These upper limits have been obtained using three independent methods that assume the gravitational wave emission follows the radio timing. Two of the methods produce frequentist upper limits for an assumed known orientation of the star's spin axis and value of the wave polarization angle of, respectively, $1.9\ee{-24}$ and $2.2\ee{-24}$, with 95% confidence. The third method, under the same hypothesis, produces a Bayesian upper limit of $2.1\ee{-24}$, with 95% degree of belief. These limits are below the …
Search For Gravitational Wave Bursts From Six Magnetars, Duncan Brown, J. Abadie
Search For Gravitational Wave Bursts From Six Magnetars, Duncan Brown, J. Abadie
Physics - All Scholarship
Soft gamma repeaters (SGRs) and anomalous X-ray pulsars (AXPs) are thought to be magnetars: neutron stars powered by extreme magnetic fields. These rare objects are characterized by repeated and sometimes spectacular gamma-ray bursts. The burst mechanism might involve crustal fractures and excitation of non-radial modes which would emit gravitational waves (GWs). We present the results of a search for GW bursts from six galactic magnetars that is sensitive to neutron star f-modes, thought to be the most efficient GW emitting oscillatory modes in compact stars. One of them, SGR 0501+4516, is likely ~1 kpc from Earth, an order of magnitude …