UScholar Works
 
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CreatorTitleDescriptionSubjectDate
326 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
327 Sokolsky, PierreHighest-energy cosmic raysWhat in the cosmos can possibly be accelerating protons to 1020 electron volts and beyond? And how can they preserve such extreme energies while plowing through the cosmic microwave background on their way to us?Energy spectrum; GZK cutoff; Atmospheric fluorescence1998
328 Wu, Yong-ShiHolography and noncommutative Yang-Mills theoryIn this Letter a recently proposed gravity dual of noncommutative Yang-Mills theory is derived from the relations between closed string moduli and open string moduli recently suggested by Seiberg and Witten. The only new input one needs is a simple form of the running string tension as a function ...Noncommutativity; String theory; Gravity dual2000-03
329 Vardeny, Zeev ValentineHot-carrier thermalization in amorphous siliconThermalization of photoinduced carriers in a-Si and α-Si:H was studied with use of sub-picosecond-pump and probe techniques with parallel and perpendicular polarizations. The underlying process was identified as hot-carrier absorption whose cross section increases with the carrier excess energy. T...Amorphous silicon; Thermalization; Photoinduced carriers; Frohlich interaction1981-05
330 Dawson, KyleHST discovery of a z=3.9 multiply imaged galaxy behind the complex cluster lens WARPS J1415.1+36 at z=1.026We report the discovery of a multiply lensed Lyα_x000B_ emitter at z=3.90 behind the massive galaxy cluster WARPS J1415.1+3612 at z=1.026. Images taken by the Hubble Space Telescope (HST) using ACS reveal a complex lensing system that produces a prominent, highly magnified arc and a triplet of smal...2009-12-10
331 Lupton, John MarkHyperfine-field-mediated spin beating in electrostatically bound charge carrier pairsOrganic semiconductors offer a unique environment to probe the hyperfine coupling of electronic spins to a nuclear spin bath. We explore the interaction of spins in electron-hole pairs in the presence of inhomogeneous hyperfine fields by monitoring the modulation of the current through an organic li...Spin beating; Electrostatically-bound; Charge carrier pairs; Electronic spins; Nuclear spin bath; Organic light-emitting diodes2010-01
332 Wu, Yong-ShiIdentification of androgen response elements in the insulin-like growth factor I upstream promoterTestosterone stimulates the expression of IGF-I in cells and tissues that include prostate, muscle and muscle satellite cells, and the uterus. Here, the molecular mechanisms of this effect of testosterone were explored. Testosterone increased IGF-I mRNA levels in HepG2 and LNCaP cells and stimulated...IFG-I; Androgen-responsive elements2007
333 Vardeny, Zeev Valentine; Ehrenfreund, Eitan A.Illumination-induced metastable polaron-supporting state in poly(p-phenylene vinylene) filmsWe found an illumination-induced metastable polaron-supporting state in films of a soluble derivative of poly-p-phenylene vinylene (MEH-PPV). Pristine, nonilluminated MEH-PPV polymer films do not show longlived photogenerated polarons. Prolonged UV illumination, however, is found to induce a revers...Metastable polaron-supporting state; Poly(p-phenylene vinylene); PPV; MEH-PPV; Excitons2007-07
334 Wu, Yong-ShiImplications of a cosmological constant varying as R-2We advocate the possibility that the (effective) cosmological constant A varies in time as R- 2, R being the scale factor of our expanding Universe. This behavior can be obtained under some simple and general assumptions in conformity with quantum cosmology. After pointing out several advantages w...Cosmological constant1990-01
335 Mattis, Daniel C.Implications of infrared instability in a two-dimensional electron gasWe consider the tight-binding energy band in sq lattices and determine that in the half-filled case there exists an infrared instability in addition to the 2kF (nesting)-type instability. In view of the pseudo-two-dimensional band structure of La2-xBaxCu04 recently proposed by Jorgensen et al. and b...Fermi surface; Bosonization1987-07
336 Gondolo, PaoloImplications of muon anomalous magnetic moment for supersymmetric dark matterThe anomalous magnetic moment of the muon has recently been measured to be in conflict with the standard model prediction with an excess of 2.6s. Taking the excess at face value as a measurement of the supersymmetric contribution, we find that at 95% confidence level it imposes an upper bound of 50...Magnetic moment; Neutralinos2001-05
337 Gondolo, PaoloImproved constraints on supersymmetric dark matter from muon g-2The new measurement of the anomalous magnetic moment of the muon by the Brookhaven AGS experiment 821 again shows a discrepancy with the standard model value. We investigate the consequences of these new data for neutralino dark matter, updating and extending our previous work [E. A. Baltz and P. ...Magnetic moment; Neutralinos2003-03
338 Mattis, Daniel C.Improved Landau-Ginzburg equation near surfaces of solidsWe study the order parameter near the surface for an Ising model. Applications to the lattice gas, alloy problem, and ferromagnetism are noted. Away from Tc our equations differ from the Landau-Ginzburg results due to an additional nonlinear, term which can substantially affect the order parameter...Landau-Ginzburg equation; Boundary conditions1980-12
339 Gerton, JordanImproved localization accuracy in stochastic super-resolution fluorescence microscopy by K-factor image deshadowingLocalization of a single fluorescent particle with sub-diffraction-limit accuracy is a key merit in localization microscopy. Existing methods such as photoactivated localization microscopy (PALM) and stochastic optical reconstruction microscopy (STORM) achieve localization accuracies of single emitt...2014-01-01
340 DeTar, CarletonImproving flavor symmetry in the Kogut-Susskind hadron spectrumWe study the effect of modifying the coupling of Kogut-Susskind quarks to the gauge field by replacing the link matrix in the quark action by a ‘‘fat link,'' or sum of link plus three-link paths. Flavor symmetry breaking, determined by the mass difference between the Goldstone and non-Goldston...Kogut-Susskind quarks; Flavor symmetry; Fat links1997-02
341 Gondolo, PaoloIndirect detection of a subdominant density component of cold dark matterWe examine the detectability through indirect means of weakly interacting dark matter candidates that may constitute not all but only a subdominant component of galactic cold dark matter. We show that the possibility of indirect detection of neutralinos from their annihilations in the Earth and Su...WIMP; Weakly interacting massive particles; Annihilations2003-01
342 Gondolo, PaoloIndirect detection of dark matter in km-size neutrino telescopesNeutrino telescopes of kilometer size are currently being planned. They will be two or three orders of magnitude bigger than presently operating detectors, but they will have a much higher muon energy threshold. We discuss the trade-off between area and energy threshold for indirect detection of neu...Neutrino telescopes; Energy threshold; Neutralino annihilations; Supersymmetric models1998-11
343 Gondolo, PaoloIndirect detection of dark matter in km-size neutrino telescopesNeutrino telescopes of kilometer size are currently being planned. They will be two or three orders of magnitude larger than presently operating detectors, but they will have a much higher muon energy threshold. We discuss the trade-off between area and energy threshold for indirect detection of ne...Neutrino telescopes; Energy threshold; Neutralino annihilations; Supersymmetric models1999
344 Gondolo, PaoloIndirect neutralino detection rates in neutrino telescopesNeutralinos annihilating in the center of the Sun or the Earth may give rise to a detectable signal of neutrinos. We derive the indirect detection rates for neutrino telescopes in the minimal supersymmetric extension of the standard model. We show that even after imposing all phenomenological and e...Neutralinos; Neutrino telescopes; Relic density; Annihilations1997-02
345 Boehme, ChristophInfluence of disorder on electrically and optically detected electron spin nutationA numerical study of the influence of disorder in semiconductors on spin-Rabi nutation observed with pulsed electrically or optically detected magnetic-resonance techniques (pEDMR and pODMR, respectively ) is presented. It is shown that transient nutation signals of disordered spin ensembles differ ...Electron spin nutations2009-02
346 Rogachev, AndreyInfluence of high magnetic fields on the superconducting transition of one-dimensional Nb and MoGe nanowiresThe effects of a strong magnetic field on superconducting Nb and MoGe nanowires with diameter ~10 nm have been studied. We have found that the Langer-Ambegaokar-McCumber-Halperin (LAMH) theory of thermally activated phase slips is applicable in a wide range of magnetic fields and describes well the ...Nb; MoGe; Superconducting transition; Langer-Ambegaokar-McCumber-Halperin; LAMH; Phase slips2005-01
347 Mishchenko, EugeneInfrared absorption and Raman scattering on coupled plasmon-phonon modes in superlatticesWe consider theoretically a superlattice formed by thin conducting layers separated spatially between insulating layers. The dispersion of two coupled phonon-plasmon modes of the system is analyzed by using Maxwell's equations, with the influence of retardation included. Both transmission for the fi...Infrared absorption; Raman scattering2006-04
348 Vardeny, Zeev ValentineInfrared ultrafast optical probes of photoexcitations in ∏-conjugated organic semiconductorsWe measured the ultrafast dynamics of photoexcitations in a variety of semiconductor ∏-conjugated polymer films and solutions, in the spectral range from 0.13 eV to 1.05 eV and time domain from 100 fs to 800 ps. The measurements were made in the low signal regime, where the relative changes in tra...Infrared ultrafast optical probes; Photoexcitations; Ultrafast dynamics; MEH-PPV2005
349 Williams, Clayton C.Instability induced tunneling and repeatable charge injection to SiO2 surfaces by electrostatic force microscopyThe dynamic response and stability of a voltage biased oscillating cantilever in the proximity of an insulating sample surface is investigated. As the tip approaches the sample surface, the cantilever can jump between two different oscillation modes. The jump is detected as an abrupt increase in t...Electrostatic force microscopy; EFM; Dielectric films2004
350 Wu, Yong-ShiIntegrable open spin chain in super Yang-Mills and the plane-wave/SYM dualityWe investigate the integrable structures in an N = 2 superconformal Sp(N) Yang-Mills theory with matter, which is dual to an open+closed string system. We restrict ourselves to the BMN operators that correspond to free string states. In the closed string sector, an integrable structure is inherited ...2004-02-01
326 - 350 of 924