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1.5D Quasilinear Model for Alpha Particle-TAE Interaction in ARIES ACT-I

Description: We study the TAE interaction with alpha particle fusion products in ARIES ACT-I using the 1.5D quasilinear model. 1.5D uses linear analytic expressions for growth and damping rates of TAE modes evaluated using TRANSP pro les to calculates the relaxation of pressure pro les. NOVA- K simulations are conducted to validate the analytic dependancies of the rates, and to normalize their absolute value. The low dimensionality of the model permits calculating loss diagrams in large parameter spaces.
Date: January 30, 2013
Creator: Ghantous, K.; Gorelenkov, N. N.; Kessel, C. & Poli, F.
Partner: UNT Libraries Government Documents Department

Design, Synthesis and Optoelectronic Properties of Monovalent Coinage Metal-Based Functional Materials toward Potential Lighting, Display and Energy-Harvesting Devices

Description: Groundbreaking progress in molecule-based optoelectronic devices for lighting, display and energy-harvesting technologies demands highly efficient and easily processable functional materials with tunable properties governed by their molecular/supramolecular structure variations. To date, functional coordination compounds whose function is governed by non-covalent weak forces (e.g., metallophilic, dπ-acid/dπ-base stacking, halogen/halogen and/or d/π interactions) remain limited. This is unlike the situation for metal-free organic semiconductors, as most metal complexes incorporated in optoelectronic devices have their function determined by the properties of the monomeric molecular unit (e.g., Ir(III)-phenylpyridine complexes in organic light-emitting diodes (OLEDs) and Ru(II)-polypyridyl complexes in dye-sensitized solar cells (DSSCs)). This dissertation represents comprehensive results of both experimental and theoretical studies, descriptions of synthetic methods and possible application allied to monovalent coinage metal-based functional materials. The main emphasis is given to the design and synthesis of functional materials with preset material properties such as light-emitting materials, light-harvesting materials and conducting materials. In terms of advances in fundamental scientific phenomena, the major highlight of the work in this dissertation is the discovery of closed-shell polar-covalent metal-metal bonds manifested by ligand-unassisted d10-d10 covalent bonds between Cu(I) and Au(I) coinage metals in the ground electronic state (~2.87 Å; ~45 kcal/mol). Moreover, this dissertation also reports pairwise intermolecular aurophilic interactions of 3.066 Å for an Au(I) complex, representing the shortest ever reported pairwise intermolecular aurophilic distances among all coinage metal(I) cyclic trimetallic complexes to date; crystals of this complex also exhibit gigantic luminescence thermochromism of 10,200 cm-1 (violet to red). From applications prospective, the work herein presents monovalent coinage metal-based functional optoelectronic materials such as heterobimetallic complexes with near-unity photoluminescence quantum yield, metallic or semiconducting integrated donor-acceptor stacks and a new class of Au(III)-based black absorbers with cooperative intermolecular iodophilic (I…I) interactions that sensitize the harvesting of all UV, all visible, and a broad spectrum of near-IR ...
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Date: August 2017
Creator: Ghimire, Mukunda Mani
Partner: UNT Libraries

Photography Changes Our Environmental Awareness

Description: This article is part of a series by the Smithsonian Photography Initiative called Click! Photography Changes Everything. This article discusses how photography and increased visibility can bridge the gap between the natural world and human interaction.
Date: 2011
Creator: O'Connor, Brian Clark & Klaver, Irene
Partner: UNT College of Information


Description: A bibliography on pion-pion interactions is presented. The 241 references are those available through November 7, 1961. A chronological listing is given together with excerpts or comments. In another part the references are grouped according to subject. An author index is included. (M.C.G.)
Date: November 1, 1961
Creator: Stevenson, M.L.
Partner: UNT Libraries Government Documents Department

Experimental studies of elementary-particle interactions at high energies. Technical progress report

Description: The experimental high energy physics research at Rockefeller University is described. Status of the R-108 experiment at the CERN ISR is briefly described, and the research program at Fermilab is outlined. The analysis of Fermilab experiment No. 396, designed to measure the elastic and diffractive dissociation cross sections of ..pi../sup +-/, K/sup +-/, and p/sup +-/ on p at 0.03 to 0.1 (GeV/c)/sup 2/, has been completed. Test data take with a new experimental setup (TREAD) for studying low t elastic and diffraction scattering by photons and hadrons are briefly discussed. (WHK)
Date: November 1, 1981
Creator: None
Partner: UNT Libraries Government Documents Department

Status of heavy-lepton searches

Description: Searches for heavy leptons using e{sup +}e{sup -} annihilation, lepton-hadron collisions, photon-hadron collisions, hadron-hadron collisions, and studies of macroscopic matter are reviewed. The present experimental status and future possibilities are summarized.
Date: June 1, 1981
Creator: Perl, M.L.
Partner: UNT Libraries Government Documents Department

Elastic scattering of neutrinos by electrons and protons

Description: Measurements of the cross sections for neutrino and antineutrino elastic scattering by both electrons and protons are presented. These measurements were done at the Brookhaven AGS by the E734 Collaboration (Brookhaven/Brown/KEK/Osaka/Pennsylvania/Stony Brook). These results are then used to determine the weak mixing angle sin/sup 2/theta/sub w/. 6 refs., 3 figs.
Date: January 1, 1985
Creator: Hedin, D.
Partner: UNT Libraries Government Documents Department

Inclusive quarkonium production

Description: In the approximation of zero binding energy, the production of the heavy vector quarkonium states V(= psi, T,...) accompanied with gluon (g) jets in ..gamma..N and e/sup +/e/sup -/ collisions is studied. For the rare decay of the Z/sup 0/ resonance into Vgg, the rate is found extremely small.
Date: January 1, 1981
Creator: Keung, W.Y.
Partner: UNT Libraries Government Documents Department

Search for narrow B anti B(. pi. ) states in 16 GeV/c. pi. /sup -/p and 5 GeV/c anti pp interactions

Description: The searches for narrow baryon-antibaryon (B anti B) bound states from two recent experiments carried out at the BNL Multiparticle Spectrometer are reported. First, the results of a search for narrow states in the anti pp, ..lambda..p..pi../sup + -/ and anti pp..pi../sup +/ systems from ..pi../sup -/p interactions at 16 GeV/c are presented. The data come from an experiment carried out by physicists from BNL, Brandeis, CCNY, Southeastern Massachusetts, University of Massachusetts. Next, results are shown of a search for narrow anti pp states from anti pp interactions at 5 GeV/c, an experiment with collaborators from BNL, Brandeis, University of Cincinnati, Florida State University, and Southeastern Massachusetts University.
Date: January 1, 1980
Creator: Chung, S U
Partner: UNT Libraries Government Documents Department

Probing color-singlet exchange at D0

Description: We present latest preliminary results on hard color-singlet exchange in proton-antiproton collisions. The fraction of dijet events produced via color-singlet exchange is measured as a function of jet transverse energy, dijet pseudorapidity separation, and proton-antiproton center-of-mass energy. These results are qualitatively consistent with a color-singlet fraction that increases with increasing quark-initiated processes.
Date: July 1, 1997
Creator: Abbott, B.; Abolins, M.; Acharya, B.S. & Collaboration, D0
Partner: UNT Libraries Government Documents Department

A Measurement of {chi}F{nu over 3}-{chi}F{nubar over 3} and R with the CCFR Detector

Description: We report on a measurement of the neutrino-nucleon and antineutrino-nucleon differential cross sections in the CCFR detector. The measurement of the differential cross sections over a wide range of energies allows {Delta}xF<sub>3</sub> = xF<sup>{nu}</sup><sub>3</sub> -xF<sup>{anti {nu}}</sup><sub>3</sub> and R to be extracted. {Delta}xF</sub>3</sub> is related to the difference between the contributions of the strange and charm seas in the nucleon to production of massive charm quark. The results for {Delta}xF</sub>3</sub> are compared to various massive charm NLO QCD models. The Q&sup2; dependence of R for x < 0.1 has been measured for the first time.
Date: July 12, 1999
Creator: al., U.K. Yang et
Partner: UNT Libraries Government Documents Department

Neutron-proton bremsstrahlung experiments

Description: It is well known that charged particles emit bremsstrahlung radiation when they are accelerated. Classical electron bremsstrahlung occurs when a photon is emitted by an electron accelerated in the field of a nucleus. The bremsstrahlung process also occurs in the scattering of nucleons, for which it is the lowest energy inelastic process that can occur. Like electron bremsstrahlung, nucleon-nucleon bremsstrahlung also requires the exchange of a virtual particle to conserve energy and momentum. In electron bremsstrahlung a virtual photon is exchanged but with two nucleons a meson can be exchanged. Unlike electron bremsstrahlung, in nucleon-nucleon bremsstrahlung the photon can originate from the exchanged meson. This exchange contribution has been shown in calculations to be a significant fraction of bremsstrahlung events. Thus bremsstrahlung serves as a probe of exchange currents in the nucleon-nucleon interaction. Because of a lack of a free neutron target or an intense neutron beam, few measurements of neutron-proton bremsstrahlung exist, each having poor statistical accuracy and poor energy resolution. The white neutron source at the Weapons Neutron Research (WNR) target area at the Los Alamos Meson Physics Facility (LAMPF) produces neutrons with energies from below 50 to above 400 MeV. Using time-of-flight techniques and a liquid hydrogen target, we are measuring the outgoing photons of energies up to 250 MeV at gamma ray angles of around 90[degree] relative to the incident beam. Protons scattered at very forward angles are also detected in coincidence with the gamma rays.
Date: January 1, 1992
Creator: Koster, J.E.; Nelson, R.O.; Schillaci, M.E.; Wender, S.A. (Los Alamos National Lab., NM (United States)); Mayo, D.; Brady, F.P. et al.
Partner: UNT Libraries Government Documents Department

Study of intermittency in e sup + e sup minus annihilations at 29 GeV

Description: Charged particle multiplicity distributions from e{sup +}e{sup {minus}} annihilations at 29 GeV have been analyzed in selected rapidity and azimuthal angle intervals. The data were taken with the High Resolution Spectrometer at PEP. The factorial moments of the multiplicity distributions increase as the rapidity interval is decreased, the so-called intermittency phenomenon. These direct measurements of the moments agree with values derived from negative binomial fits to our multiplicity distributions in various central rapidity windows. The factorial moments are also given for the distribution in azimuthal angle around the beam direction and for the two-dimensional distribution in rapidity and azimuthal angle around the jet directions.
Date: June 15, 1990
Creator: Abachi, S.; Derrick, M.; Kooijman, P.; Musgrave, B.; Price, L.; Repond, J. et al.
Partner: UNT Libraries Government Documents Department

A quark-gluon plasma search in anti p --p at radical s = 1. 8 TeV

Description: The search by E-735 for QGP evidence in centrally produced particles in {bar p}p collisions has revealed several interesting results in the behavior with variation of dN{sub c}/d{eta} in the measured interval from 2--18. In {l angle}P{sub t}{r angle} we see a decrease in slope for all particles near dN{sub c}/d{eta} {approx equal} 9 corresponding to a Bjorken initial energy density of 2.2 GeV/{sub fm}{sup 3}. Above dN{sub c}/d{eta} = 10, the increase of {l angle}P{sub t}{r angle} is small except for {bar p}'s where the data suggest a 25% increase in the region 13--18. In the particle ratios, normalizing to {pi}'s, they (K, {bar p}, {Lambda}{sup 0}, {gamma}) are all independent of dN{sub c}/d{eta} within errors of {plus minus} 15% except for K{sup {plus minus}}/{pi}{sup {plus minus}} which increases by 30% in the interval 7 to 18. Based on the E-735 data analyzed to data, one can conclude that QGP is not manifest in {bar p}p collisions at 1.8 TeV. Nonetheless, there are the two effects mentioned above, which can be explored with much improved sensitivity using the high-statistics data of the '88--'89 run.
Date: October 8, 1990
Creator: Turkot, F.
Partner: UNT Libraries Government Documents Department

Same-sign dilepton production by neutrinos

Description: There has been considerable experimental work on same-sign dilepton production in neutrino interactions over the past 10 years. However, the situation is still unclear. Most experiments do have evidence for an excess of candidates but there is a lack of independent statistically significant results. Present experiments at the Tevatron may provide important new information. However the recent revision of older results and the lower rates from recent experiments indicate that real progress will be difficult. Furthermore, the problems encountered with ..pi../K background subtractions argue for a multi-target experiment. Also, given the conflict with present c anti c calculations, a high statistics bubble chamber experiment would be useful to establish the presence/absence of c anti c events at the presently measured production rates. 13 refs., 6 figs., 2 tabs.
Date: November 7, 1985
Creator: Murtagh, M.J.
Partner: UNT Libraries Government Documents Department