UScholar Works
 
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CreatorTitleDescriptionSubjectDate
426 Gondolo, PaoloDetectability of the Sgr dwarf leading tidal stream with Auger, EUSO, or OWLWe point out that if heavy metastable particles composing the dark matter of our galaxy are responsible for the ultrahigh energy cosmic rays (UHECR) then the leading tidal stream of the Sagittarius dwarf galaxy could be detected through UHECR. The signal would be an anisotropy in the UHECR flux sma...Sagittarius dwarf galaxy; Sgr stream; anisotropy2004-07
427 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
428 Davidson, Diane W.Pruning of host plant neighbors by ants: an experimental approachSome ants of myrmecophytic plants either obligately or facultatively prune vegetation surrounding their host trees. Pruning behavior occurs at higher frequency in ants with sting defenses than in those with chemical defenses, which may generally convey an advantage in aggressive encounters between a...Allelopathy; Allomerus demararae; Ant-plant interactions; Ants; Cordia nodosa; Crematogaster; Mutualism; Peru; Plant-animal interaction; Pseudomyrmex; Triplaris americana1988
429 Carter, Tony M.Cascade: hardware for high/variable precision arithmeticThe Cascade hardware architecture for high/variable precision arithmetic is described. It uses a radix-16 redundant signed-digit number representation and directly supports single or multiple precision addition, subtraction, multiplication, division, extraction of the square root and computation...1989
430 Miller, Joel StevenCharacterization of novel TCNQ and TCNE 1 : 1 and 1 : 2 salts of the tetrakis(dimethyamino) ethylene dication, [{(CH3)2N}2C-C{N(CH3)2}2]2+Addition of TCNQ to a solution of tetrakis(dimethylamino)ethylene in MeCN produces the salt [TDAE][TCNQ]2; the dipositive cation, [{(CH3)2N}2C-C{N(CH3)2}2]2+, is nonplanar, with a dihedral angle of 63.9(o), while the TCNQ anions crystallize as [TCNQ]2 2- dimers with an interplanar separation of 3.1...Electron; Oxidations; Transfer1996
431 DeTar, CarletonEquation of state for two flavor QCD at Nt=6We calculate the two flavor equation of state for QCD on lattices with lattice spacing a=(6T)21 and find that cutoff effects are substantially reduced compared to an earlier study using a=(4T)21. However, it is likely that significant cutoff effects remain. We fit the lattice data to expected forms ...Phase transitions; Quark-gluon plasma; Dynamical quarks1997-06
432 Symko, Orest GeorgeBackground signals in SQUID magnetometersSince a SQUID magnetometer is an extremely sensitive device capable of detecting minute magnetic flux changes in a sample, it will also detect unwanted signals from materials near the magnetometer. The presence of temperature dependent "background signals" limits the accuracy of measurements of ...SQUID magnetometer; Background signals1974
433 Symko, Orest GeorgeSpin-glass behavior in dilute magnetic alloys with hcp structureA simple physical model is presented for calculating the magnetization of dilute magnetic systems with hep hosts which incorporates elements of both crystal-field theory and the molecular-field theory of spin-glasses. To permit the computation of the Ruderman-Kittel-Kasuya-Yosida contribution, the i...Spin-glass behavior; HCP structure; HCP alloys; Dilute magnetic systems; Molecular-field theory; MgMn; ZnMn1982-05
434 Gerton, JordanPhase-contrast imaging of atomic superfluid state in degenerate gas of 6Li atomsThe recent experimental realizations of Bose-Einstein condensation in trapped ultracold atomic gases composed of bosonic alkali atoms has generated a broad interest in studying different properties of these degenerate atomic Bose systems. Although the degenerate atomic gas composed of fermionic atom...1998
435 Mattis, Daniel C.Phonons and phase transitions of heliumWe find a new collective shear-wave-like mode above Tλ, merging with the longitudinal acoustic mode at a higher critical temperature. The speed of the new sound wave is predicted to vanish near Tλ as s ∞ (T -Tλ)½ .1973-06
436 Vardeny, Zeev ValentineDetection of electronic excited states in conjugated polymers by picosecond transient strain spectroscopyWe describe a new type of spectroscopy based on picosecond transient strain in absorption photomodulation that can be used to detect and identify both allowed and forbidden optical transitions in solid thin films. We have applied the new spectroscopy to a variety of conducting polymer films such as ...Picosecond transient strain spectroscopy1995-02
437 Jorgensen, ErikNeural plasticityNeural plasticity refers to functional changes in the nervous system and therefore encompasses a range of phenomena from changes at synapses observed on a microscopic scale to changes in behavior observed in the whole animal. These diverse phenomena are related since changes in synapses are believ...Synapses; Nervous System; Development1997
438 Vardeny, Zeev ValentineMagneto-optical studies of photoexcitations in C61We have used a variety of cw optical and optically detected magnetic-resonance techniques to characterize long-lived photoexeitations in methanofullerene (C6 1) as a dispersion in polystyrene glass, at temperatures below 10 K. We identify triplet excitons with zero-field-splitting (ZFS) parameters...Photoexcitations; C61; Methanofullerene1993-12
439 Wu, Yong-ShiRemarks on fractional statisticsSome issues in the theory of fractional (or intermediate) statistics are discussed with an eye on possible applications to the quantum Hall effect: spins and statistics of clusters, invariant characterization of statistics, and the effect of space topology.Fractional statistics1985-01
440 Kieda, David B.High resolution charge measurements of UH cosmic ray nuclei using a direct imaging Cherenkov ground-based observatoryThe accurate determination of the elemental composition of cosmic rays at high energies is expected to provide crucial clues on the origin of these particles. Here we discuss a technique that has become possible through the use of modern ground-based Cherenkov imaging detectors. We combine a measure...Cherenkov light; Quark star; UH nuclei; Magnetic monopole2003
441 Mishchenko, Eugene; Raikh, Mikhail E.Electrostatics of straight and bent single-walled carbon nanotubesResponse of a single-walled carbon nanotube to external electric field, F, is calculated analytically within the classical electrostatics. Field-induced charge density distribution is approximately linear along the axis of a metallic nanotube and depends rather weakly, as ln(h/ r), on the nanotube...Electrostatics2006-10
442 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
443 Jorgensen, ErikUNC-11, a Caenorhabditis elegans AP180 homologue, regulates the size and protein composition of synaptic vesiclesThe unc-11 gene of Caenorhabditis elegans encodes multiple isoforms of a protein homologous to the mammalian brain-specific clathrin-adaptor protein AP180. The UNC-11 protein is expressed at high levels in the nervous system and at lower levels in other tissues. In neurons, UNC-11 is enriched at pr...Caenorhabditis elegans; Synaptic vesicles; unc-11; Synaptobrevin; Endocytosis1999
444 Rogachev, AndreyDetermination of the superconductor-insulator phase diagram for one-dimensional wiresWe establish the superconductor-insulator phase diagram for quasi-one-dimensional wires by measuring a large set of MoGe nanowires. This diagram is roughly consistent with the Chakravarty-Schmid-Bulgadaev phase boundary, namely, with the critical resistance being equal to RQ ¼ h=4e2. Deviations fr...One-dimensional wires; Superconductor-insulator phase diagram; MoGe; Chakravarty-Schmid-Bulgadaev; Phase boundary2008-11
445 Ailion, David Charles; Morris, Alan H.Asymmetric spin echo sequences. a simple new method for obtaining NMR 1H spectral imagesThe nuclear magnetic resonance (NMR) signal decay produced by reversible tissue-induced dephasing of the magnetization components in the transverse plane (reversible tissue-induced dephasing) was measured and expressed as a function of a new transverse relaxation time T'2 (T2 prime) for samples of ...Asymmetric spin echo; Signal decay; Chemical shift; Tissue characterization; Lung aeration; Fatty liver1985
446 DeTar, CarletonQuenched hadron spectroscopy with improved staggered quark actionWe investigate light hadron spectroscopy with an improved quenched staggered quark action. We compare the results obtained with an improved gauge plus an improved quark action, an improved gauge plus standard quark action, and the standard gauge plus standard quark action. Most of the improvement ...Staggered quarks; Chiral symmetry; Flavor symmetry1998-07
447 Vardeny, Zeev ValentineDirectional emission from asymmetric microlaser resonators of ∏-conjugated polymersA ∏-conjugated polymer film was fabricated into an asymmetric microlaser resonator having a quadrapole deformation with irregular boundaries and a Q factor of 600. At high excitation intensities above the threshold for lasing, we observed multimode laser emission spectra and directional emission a...Directional emission; Asymmetric microlaser resonators; pi-conjugated polymers; DOO-PPV; poly(dioctyloxy) phenylene vinylene2004
448 Wu, Yong-ShiSuppression of local degrees of freedom of gauge fields by chiral anomaliesA path-integral quantization is presented for the chiral Schwinger model on a Riemann surface. Gauge invariance is maintained by integrating over all gauge potentials without the usual gauge fixing. All local degrees of freedom of the gauge field are suppressed after the integration of the anomalous...Chiral anomalies; Degrees of freedom1990-08
449 Mattis, Daniel C.; Paul, PrabasajStatistical transfer matrix of a spin-glass ladderThis work concerns the Edwards-Anderson Ising model of a spin ladder, in which random bonds +_J connect nearest-neighbor Ising spins. We calculate the exact free energy of the quenched, frustrated, spin-glass-like ladder as an integral over a probability distribution P(x), the eigenfunction of a s...Thermodynamics; Ising1999
450 DeTar, CarletonExotic mesons in quenched lattice QCDSince gluons in QCD are interacting fundamental constituents just as quarks are, we expect that in addition to mesons made from a quark and an antiquark, there should also be glueballs and hybrids ~bound states of quarks, antiquarks, and gluons!. In general, these states would mix strongly with th...Hybrid mesons; Antiquarks1997-12
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