UScholar Works
 
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CreatorTitleDescriptionSubjectDate
1 Sokolsky, PierreSearch for correlations between HiRes stereo events and active galactic nucleiWe have searched for correlations between the pointing directions of ultrahigh energy cosmic rays observed by the High Resolution Fly's Eye experiment and Active Galactic Nuclei (AGN) visible from its northern hemisphere location. No correlations, other than random correlations, have been found.We ...Ultrahigh energy cosmic rays; Anisotropy2008-11
2 Gondolo, PaoloWanted! Nuclear data for dark matter astrophysicsAstronomical observations from small galaxies to the largest scales in the universe can be consistently explained by the simple idea of dark matter. The nature of dark matter is however still unknown. Empirically it cannot be any of the known particles, and many theories postulate it as a new elemen...2014-01-01
3 Vardeny, Zeev ValentineRecombination kinetics in ?-Si:HMort et al.1 reinterpreted our data on the relaxation of photoinduced absorption (PA) in a-Si:H. 2 We want to show that the proposed interpretation contradicts one basic feature of the data while our original interpretation is in good agreement with experiment.Hydrogenated amorphous silicon; a-Si:H; Recombination kinetics; Photoinduced absorption; Decay; Relaxation1981
4 Kieda, David B.High statistics search for ultrahigh energy gamma-ray emission from Cygnus X-3 and Hercules X-1We have carried out a high statistics (2 X 10 9 events) search for ultrahigh energy g-ray emission from the x-ray binary sources Cygnus X-3 and Hercules X-1. Using data taken with the CASA-MIA detector over a five year period (1990-1995), we find no evidence for steady emission from either source. T...Cygnus X-3; Hercules X-1; Ultrahigh energy; X-rays1997
5 Sokolsky, PierreHigh Resolution Fly's Eye - status and preliminary results on cosmic ray composition above 10^18 eVWe describe the current status of the High Resolution Fly's Eye detector. Event reconstruction and associated systematics for stereo reconstruction are discussed and recent preliminary results on the study of the composition of ultra-high energy cosmic rays by the Xmax method are presented. These r...Ultra-high energy cosmic rays; Fluorescence; Stereo detection2002
6 Sokolsky, PierreTotal proton-proton cross section at s1/2=30 TeVWe have measured the proton-air inelastic cross section at s 1/2 = 30 TeV by observing the distribution of extensive-air-shower maxima as a function of atmospheric depth. This distribution has an exponential tail whose slope is λ = 72 ±9 g c m - 2 which implies that σ inel p-air = 530 ± 66 mb. U...1984-04
7 Symko, Orest GeorgeExchange interactions and magnetic dimension in Cu(L-alanine)2A study of the magnetic properties of the copper (II) complex of the amino acid L-alanine [CU(Lalanine) 2] is reported. The susceptibility of a powder sample has been measured between 0.013 and 240 K. A linear-spin-chain model with antiferromagnetic exchange coupling J = -0.52 K fits well the susce...Cu(L-alanine)2; Exchange interactions; Magnetic dimension1991-01
8 Sokolsky, PierreHighest energy cosmic rays and results from the HiRes experimentThe status of the field of ultrahigh energy cosmic ray physics is summarized, from the point of view of the latest results of the High Resolution Fly's Eye (HiRes) Experiment. HiRes results are presented, and compared with those of the Akeno Giant Air Shower Array (AGASA), plus the Telescope Array ...Fluorescence; Energy spectrum; GZK cutoff; Extensive air showers; Anisotropy2007-11-01
9 Sokolsky, PierreEvidence for 10^18-eV neutral particles from the direction of Cygnus X-3Analysis of the cumulative Fly's Eye data reveals an excess of air showers from the direction of Cygnus X-3 at energies above 0.5 x 10^18 eV. No point source has previously been identified at such high energies. The probability of this excess arising as a chance clustering of isotropic cosmic rays i...Cygnus X-3; Extensive air showers; Neutral particles1989-01
10 DeTar, CarletonThermodynamic properties of the gluon plasmaWe calculate the energy density, pressure, and speed of sound in the deconfined phase of lattice SU(3) gauge theory at finite temperature for lattices of temporal size N,=4, 6, and 8. We compare our results with perturbative QCD at high temperature and with a simple phenomenological model. We also p...Hadronic matter; Energy density; Gluon plasma; Phase transitions1987-01
11 Williams, Clayton C.Lateral dopant profiling in MOS structures on a 100 nm scale using scanning capacitance microscopyScanning capacitance microscopy and atomic force microscopy have been used to image the extent of lateral dopant diffusion in MOS structures. The data are capacitance vs. voltage measurements made on a submicron scale. The technique is non-destructive when imaging uncleaved samples. New experim...Scanning capacitance microscopy; Dopant profiling1990
12 DeTar, CarletonTwo-flavor staggered fermion thermodynamics at Nt = 12We present results of an ongoing study of the nature of the high temperature crossover in QCD with two light fermion flavors. These results are obtained with the conventional staggered fermion action at the smallest lattice spacing to date, approximately 0.1 fm. Of particular interest are (1) a stu...Staggered fermions; Phase transitions; Polyakov loop1996-10
13 Wu, Yong-ShiAnalyzing powers for ∏±-13C scattering at T∏=100 MeVMeasurements of the analyzing power for the nC(rr±,rr±) reaction at Trr = 100 MeV have been made at TRIUMF using a polarized target consisting of 99% 1 3C enriched butanol. Data were obtained for the ground and 3.68 MeV excited states at angles from 110° to 150° in 10° steps. The data are con...1992-02
14 Gerton, JordanTip-enhanced fluorescence microscopy of high-density samplesHigh-density samples of fluorescent quantum dots (QDs) were imaged using an apertureless near-field optical microscopy technique. QD fluorescence was modulated by oscillating a silicon atomic force microscope tip above an illuminated sample and a lock-in amplifier was used to suppress background fr...2006
15 DeTar, CarletonString breaking in lattice quantum chromodynamicsThe separation of a heavy quark and antiquark pair leads to the formation of a tube of flux, or string, which should break in the presence of light quark-antiquark pairs. This expected zero temperature phenomenon has proven elusive in simulations of lattice QCD. We present simulation results that sh...String breaking; Antiquarks; Polyakov loop; Dynamical fermions1998-12
16 Williams, Clayton C.Scanning capacitance microscope methodology for quantitative analysis of P-N junctionsQuantification of dopant profiles in two dimensions (2D) for p-n junctions has proven to be a challenging problem. The scanning capacitance microscope (SCM) capability for p-n junction imaging has only been qualitatively demonstrated. No well-established physical model exists yet for the SCM data in...p-n junctions; Scanning capacitance microscope; SCM1999
17 Ailion, David CharlesNMR observations of molecular motions and Zeeman-quadrupole cross relaxation in 1,2- difluorotetrachloroethaneWe report measurements of "F NMR relaxation times Tu Tlf, TID, and T2 in the plastic crystal CFCL2-CFCL2 . From the data near the melting point, we obtain the jump time for translational selfdiffusion. At lower temperatures, we observe on the cold side of the T, and Tif minima an unusual field depe...NMR; Nuclear magnetic resonance; Order-disorder; Diffusion1979
18 DeTar, CarletonStatic screening lengths in the gluon plasmaWe report results of an extensive numerical simulation in lattice gauge theory to study various static screening lengths in a finite-temperature pure gluon plasma. Measurements are made for fixed triplet charges (Wilson lines) and a variety of local operators near and above the phase transition for ...Gluon plasma; Phase transitions; Deconfinement; Strange quarks1986-10
19 Kieda, David B.; Gaisser, Thomas K.; Sokolsky, PierreCosmic-ray composition around 10^18 eVWe use the depth of maximum distribution as measured by the stereo Fly's Eye detector to study the chemical composition of the primary cosmic radiation between 3x 1017 eV and 1019 eV. The analysis depends on the use of simulations to study the response of the detector as well as sensitivity to assum...Fly's Eye; Cosmic ray composition; Cosmic ray nuclei; Chemical composition1993-03
20 Sokolsky, PierreCosmic-ray composition around 10^18 eVWe use the depth of maximum distribution as measured by the stereo Fly's Eye detector to study the chemical composition of the primary cosmic radiation between 3 x 10^17 eV and 10^19 eV. The analysis depends on the use of simulations to study the response of the detector as well as sensitivity to as...Energy spectrum; Extensive air showers; Inelasticity; Hadronic interactions1993-03
21 Symko, Orest GeorgeSpin freezing below the nearest-neighbor percolation concentration in Cd1-xMnxTe and Cd1-xMnxSeThe very-low-temperature magnetization of Cdi_xMnxTe and Cdj-xMnxSe alloys shows spinglass behavior for concentrations below the nearest-neighbor percolation limit. This is attributed to short-range exchange and dipolar interactions. New magnetic phase diagrams for both systems are presented.Spin freezing; Cd1-xMnxTe; Cd1-xMnxSe; Very-low-temperature magnetization; Spin-glass behavior1986-05
22 DeTar, CarletonB→πlν semileptonic form factor from three-flavor lattice QCD: a model-independent determination of [Vub]We calculate the form factor f+(q2) for B-meson semileptonic decay in unquenched lattice QCD with 2 + 1 flavors of light sea quarks. We use Asqtad-improved staggered light quarks and a Fermilab bottom quark on gauge configurations generated by the MILC Collaboration. We simulate with several light...Semileptonic decay2009-03
23 Sokolsky, PierreMeasurement of the flux of ultrahigh energy cosmic rays from monocular observations by the High Resolution Fly's Eye experimentWe have measured the cosmic ray spectrum above 1017.2 eV using the two air-fluorescence detectors of the High Resolution Fly's Eye observatory operating in monocular mode.We describe the detector, phototube, and atmospheric calibrations, as well as the analysis techniques for the two detectors.We fi...Extensive air showers; Fluorescence; Energy spectrum2004-04
24 Ailion, David CharlesMolecular reorientations in the ordered phases of KCN and NaCN studied by NMRWe have measured 13C and 23Na NMR spin-lattice relaxation times as a function of temperature in KCN and NaCN in order to study the head-to-tail reorientations of the CN- molecules in the two low-temperature ordered phases. We have combined our data with those of dielectric-response and ionic-thermal...Spin; Interactions; Fluctuations1984
25 Sokolsky, PierreFirst observation of the Greisen-Zatsepin-Kuzmin suppressionThe High Resolution Fly's Eye (HiRes) experiment has observed the Greisen-Zatsepin-Kuzmin suppression (called the GZK cutoff) with a statistical significance of five standard deviations. HiRes' measurement of the flux of ultrahigh energy cosmic rays shows a sharp suppression at an energy of 6 x 10^1...Extensive air showers; Suppression; Energy spectrum; Fluorescence; GZK cutoff2008-03
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