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CreatorTitleDescriptionSubjectDate
176 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
177 Mishchenko, EugeneZero-bias anomaly in disordered wiresWe calculate the low-energy tunneling density of states v(ε, T) of an N-channel disordered wire, taking into account the electron-electron interaction nonperturbatively. The finite scattering rate 1/r results in a crossover from the Luttinger liquid behavior at higher energies, v ∞ εa, to the ...Disordered wires; Luttinger liquid; Coulomb interaction2001-11
178 Ailion, David CharlesStudy of utraslow atomic motions by magnetic resonanceMagnetic resonance has been widely used to study phenomena such as atomic diffusion and molecular reorientation. It is applicable when the mean time, r, between atomic jumps is either (a) sufficiently short to narrow the resonance line width or (b) of the correct magnitude to produce spin-lattice ...Atomic motion; Magnetic resonance; Ultraslow atomic motion1964
179 Gerton, JordanNanoscale fluorescence imaging using a single-wall carbon nanotubeA single-wall carbon nanotube attached to an AFM probe is used for near-field optical imaging of 20 nm diameter fluorescent spheres and 5 nm diameter CdSe quantum dots.2007-05
180 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
181 DeTar, CarletonScalar meson spectroscopy with lattice staggered fermionsWith sufficiently light up and down quarks the isovector (a0) and isosinglet (f0) scalar meson propagators are dominated at large distance by two-meson states. In the staggered-fermion formulation of lattice quantum chromodynamics, taste-symmetry breaking causes a proliferation of two-meson states t...Staggered fermions; Chiral theory2007-11
182 DeTar, CarletonQuark-bag model with low-energy pion interactions. I. TheoryA standard method for restoring chiral symmetry in the bag model is to introduce an explicit external pion field. Questions of the consistency and compatibility of this method with the assumptions of the static-cavity approximation of the bag model are discussed. An approximate version of the mode...Bag models; Quark bag; Chiral symmetry; Pion bag; Pion field1981-08
183 Mattis, Daniel C.Role of Fermi surface and crystal structure in theory of magnetic metalsWe have investigated the magnetic ground state of metals using an idealized theory of magnetism based on the Ruderman-Kittel-Yosida indirect exchange interaction. The preliminary, but suggestive, results reported here are for simple cubic structures and spherical Fermi surface. We find that as the...Magnetic metals; Crystal structure1962-11
184 Vardeny, Zeev ValentineOrganic random lasers in the weak-scattering regimeWe used the ensemble-averaged power Fourier transform (PFT) of random laser emission spectra over the illuminated area to study random lasers with coherent feedback in four different disordered organic gain media in the weak scattering regime, where the light mean free path, ℓ* is much larger tha...Organic random lasers; Gain media; pi-conjugated polymers; Opal photonic crystal; RG6; Optical gain; Chicken breast2005-01
185 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
186 Wu, Yong-ShiStatistical distribution for generalized ideal gas of fractional-statistics particlesWe derive the occupation-number distribution in a generalized ideal gas of particles obeying fractional statistics, including mutual statistics, by adopting a state-counting definition. When there is no mutual statistics, the statistical distribution interpolates between bosons and fermions, and re...Fractional statistics; Ideal gas1994-08
187 Vardeny, Zeev Valentine; Raikh, Mikhail E.Mesoscopic cooperative emission from a disordered systemWe study theoretically the cooperative light emission from a system of N»1 classical oscillators confined within a volume with spatial scale L much smaller than the radiation wavelength λο=2rrc/ω0. We assume that the oscillator frequencies are randomly distributed around a central frequency ω...Mesoscopic cooperative emission; Disordered systems; Oscillators2000-05
188 Vardeny, Zeev ValentineOptical studies of spin coherence in organic semiconductorsSpin coherence in organic oligomer and polymer semiconductors is a crucial property in determining the performance of organic spin devices. Using the techniques of photo-induced absorption (PA) detected magnetic resonance (PADMR) and photoluminescence (PL) detected magnetic resonance (PLDMR), we ha...Spin coherence; Organic spin devices2005
189 DeTar, CarletonRecent MILC spectrum results*We report on results from three spectrum calculations with staggered quarks: 1) a quenched calculation with the standard action for the gluons and quarks; 2) a quenched calculation with improved actions for both the gluons and quarks; and 3) a calculation with two flavors of dynamical quarks using...Staggered quarks; Hadron spectrum1997-02
190 DeTar, CarletonMultiperipheral dynamics at general momentum transferWe extend the group-theoretical analysis of the multiperipheral integral equation of Chew, Goldberger, and Low to general momentum transfers. Using a set of variables for the multiparticle phase space analogous to those of Bali, Chew, and Pignotti, we obtain, through the 0(2,1) symmetry, a partial...Multiperipheral model1969-12
191 Mattis, Daniel C.Theory of the magnetic polaronWe construct exact Green's functions for a single electron in a ferromagnetic semiconductor, including both spin-conserving and spin-flip processes at T = 0. We contrast two cases: ferromagnetic and antiferromagnetic coupling of the electron's spin to the lattice. In the former case, a small-k elect...Scattering states; Electric transport1981-11
192 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
193 Vardeny, Zeev ValentineTransport studies of isolated molecular wires in self-assembled monolayer devicesWe have fabricated a variety of isolated molecule diodes based on self-assembled monolayers (SAM) of solid-state mixture (SSM) of molecular wires [1,4-methane benzene dithiol (Me-BDT)], and molecular insulator spacers [penthane 1-thiol (PT)] with different concentration ratios r of wires/spacers, wh...Transport studies; Molecular wires; Monolayer devices2005
194 DeTar, CarletonCritical behavior in Nt=4 staggered fermion thermodynamicsQuantum chromodynamics with two zero mass flavors is expected to exhibit a phase transition with O(4) critical behavior. Fixing the universality class is important for phenomenology and for facilitating the extrapolation of simulation data to physical quark mass values. Other groups have reported r...Staggered fermions; Phase transitions; Quark-gluon plasma; Chiral symmetry2000-01
195 Vardeny, Zeev ValentinePhotoexcitations in disubstituted acetylene polymersWe have used a variety of optical techniques to study the photoexcitations dynamics in several disubstituted acetylene polymer thin films. We found that although these polymers have a degenerate ground state, as determined by iodine doping and C6Q photodoping, they show strong photoluminescence (PL)...Photoexcitations; Disubstituted acetylene polymers; Trans-Polyacetylene; Electron-electron interactions1997
196 Ailion, David Charles93Nb NMR in the imcommensurate and quasi-commensurate phases of barium sodium niobateNMR spectra have been measured for the quadrupole perturbed 1/2 -1/2 transition of 9 3Nb in barium sodium niobate (BSN) between 300 and 650 K. The spectra are inhomogeneously broadened in the incommensurate (/) phase between T7 = 580 K and r c = 540 K as well as in the quasicommensurate (QC) phase ...NMR; Spectra; Barium sodium niobate; Line shapes1994
197 Wu, Yong-ShiChiral bosonization and local Lorentz-invariant actions for chiral bosonsWe formulate a geometrical theory of self-dual scalar fields in two dimensions with a local Lorentz-invariant action. Path-integral quantization is used to derive chiral bosonization by demonstrating equivalence of correlation functions of currents and energy-momentum tensors in our theory with thos...Bosonization; String theory; Weyl fermions1988-06
198 Lupton, John MarkEfficient dipole-dipole coupling of Mott-Wannier and Frenkel excitons in (Ga,In)N quantum well/polyfluorene semiconductor heterostructuresWe investigate interactions between Mott-Wannier (MW) and Frenkel excitons in a family of hybrid structures consisting of thin organic (polyfluorene) films placed in close proximity (systematically adjusted by GaN cap layer thickness) to single inorganic [(Ga, In)N/GaN] quantum wells (QWs). Charac...Mott-Wannier; Frenkel; Excitons; Dipole-dipole coupling; Semiconductor heterostructures2007-07
199 Williams, Clayton C.Nanometer scale absorption spectroscopy by near-field photodetection optical microscopyNear-field photodetection optical microscopy (NPOM) is a fundamentally new approach to near-field optical microscopy. This scanning probe technique uses a nanometer-scale photodiode detector which absorbs optical power directly as it is scanned in the near field of an illuminated sample surface. ...Near-field photodetection optical microscopy; NPOM; Nanoscale; Photodiode1996
200 Kieda, David B.Observation of the shadows of the moon and sun using 100 TeV cosmic raysThe Chicago Air Shower Array (CASA) is a large ground-based scintillation detector [1-4]. It is located at the Dugway Proving Ground is west central Utah, latitude 40°N and mean atmospheric depth 870 g / c m 2. A schematic aerial view of CASA is shown in Fig. 1. Each dot represents one scintil...Chicago Air Shower Array; Scintillation detectors; Ultrahigh energy cosmic rays1994-02
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