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B physics at the tevatron

Description: Precision B-physics results from the CDF and D0 Collaborations based on data collected during the Tevatron 1992-96 run are presented. In particular we discuss the measurement of the B{sub s} meson lifetime, B{sub c} meson observation, and B{sup 0} - {anti B}{sup 0} mixing results obtained using time-evolution analyses. Prospects for the next Tevatron run, starting in 1999, are also reported.
Date: July 1, 1998
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The physics of fast Z pinches

Description: The spectacular progress made during the last few years in reaching high energy densities in fast implosions of annular current sheaths (fast Z pinches) opens new possibilities for a broad spectrum of experiments, from x-ray generation to controlled thermonuclear fusion and astrophysics. Presently Z pinches are the most intense laboratory X ray sources (1.8 MJ in 5 ns from a volume 2 mm in diameter and 2 cm tall). Powers in excess of 200 TW have been obtained. This warrants summarizes the prese… more
Date: July 1, 1998
Creator: Ryutov, D. D.; Derzon, M. S. & Matzen, M. K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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AGS experiments in nuclear/QCD physics at medium energies

Description: This report contains a diagram of the experimental setup for each experiment as well as giving a brief discussion of its purpose and list of collaborators for the experiment. Thirty-one experiments in the areas of nuclear physics and particle physics are covered. It concludes with a list of publications of the AGS experiments.
Date: July 1, 1998
Creator: Lo Presti, P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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MPC and A upgrades at the Institute of Theoretical and Experimental Physics (ITEP)

Description: Materials Protection, Control and Accounting (MPC and A) equipment upgrades are complete at the Institute of Theoretical and Experimental Physics (ITEP), a site that has significant quantities of weapons-potential nuclear materials. Cooperative work was initiated at this Moscow facility as a part of the US-Russian program to upgrade MPC and A systems. An initial site visit and assessment were conducted in September 1996 to establish communication between ITEP, the US Department of Energy (DOE),… more
Date: July 1, 1998
Creator: Haase, M.; Smarto, C. & Baumann, M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Perspectives gained from ICRF physics studies on TFTR

Description: The physics of ICRF heating and current drive has been studied on TFTR for over a decade. Following the early low power coupling studies, high power experiments resulted in sawtooth stabilization, the first observation of RF-driven excitation of toroidal Alfven eigenmodes, and the discovery of a mode conversion scenario for localized off-axis electron heating. The program culminated with the first studies of high power ICRF heating and profile control in tritium-rich high performance plasmas. A… more
Date: July 1, 1998
Creator: Phillips, C.K.; Bell, M. & Batha, S.
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Partner: UNT Libraries Government Documents Department
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An Apparatus for the Measurement of Various Scattering Processes in Intermediate Energy, Ion - Atom Collisions

Description: This paper summarizes the main features of an apparatus constructed at the University of Toledo for the study of various scattering processes in intermediate energy, ion - atom collisions. The main purpose of this facility is to provide experimental data which serve as benchmarks to test current scattering theories for those processes. Recent measurements of single electron detachment (SED) and double electron detachment (DED) total cross sections for 5-50 keV H{sup -} ions incident on noble ga… more
Date: July 1, 1998
Creator: Kvale, T. J. & Seely, D. G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Improved intra-species collision models for PIC simulations

Description: In recent years, the authors have investigated methods to improve the effectiveness of modeling collisional processes in particle-in-cell codes. Through the use of generalized collision models, plasma dynamics can be followed both in the regime of nearly collisionless plasmas as well as in the hydrodynamic limit of collisional plasmas. They have developed a collision-field method to treat both the case of collisions between unlike plasma species (inter-species collisions), through the use of a … more
Date: July 1, 1998
Creator: Jones, Michael E.; Lemons, Don S. & Winske, Dan
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Microscopic calculation of {sup 6}Li elastic and transition form factors

Description: Variational Monte Carlo wave functions, obtained from a realistic Hamiltonian consisting of the Argonne {nu}{sub 18} two-nucleon and Urbana-IX three-nucleon interactions, are used to calculate the {sup 6}Li ground-state longitudinal and transverse form factors as well as transition form factors to the first four excited states. The charge and current operators include one- and two-body components, leading terms of which are constructed consistently with the two-nucleon interaction. The calculat… more
Date: July 1, 1998
Creator: R. B. Wiringa, R. Schiavilla
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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An investigation of resonant photoemission in Gd with x-ray linear dichroism

Description: The constructive summing of direct and indirect channels above the absorption threshold of a core level can cause a massive increase in the emission cross section, leading to a phenomenon called "resonant photoemission". Using novel magnetic linear dichroism in angular distribution photoelectron spectroscopy experiments and theoretical simulations, we have probed the nature of the resonant photoemission process in Gd metal. It now appears that temporal matching as well as energy matching is a r… more
Date: July 1, 1998
Creator: Tobin, J G
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Element-specific magnetometry with linear dichroism in photoemission

Description: In this paper, we investigate the magnetic linear dichroism in the core-level photoemission spectra of the binary alloys Co<sub>x</sub>Ni<sub>l-x</sub> and Fe<sub>x</sub>Ni<sub>1-x</sub>/Cu(100). These epitaxial films have fee structures, but very different magnetic behavior.We show that the magnetic linear dichroism in x-ray photoemission (XMLD) signal tracks the magnetization in these alloys. Comparison with recent SQUID data provides a quantitative check and endorses the view that XMLD monit… more
Date: July 1, 1998
Creator: Tobin, J G
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Study of the uncertainty of the gluon distribution

Description: The uncertainty in the calculation of many important new processes at the Tevatron and LHC is dominated by that concerning the gluon distribution function. We investigate the uncertainty in the gluon distribution of the proton by systematically varying the gluon parameters in the global QCD analysis of parton distributions. The results depend critically on the parton momentum fraction x and the QCD scale Q{sup 2}. The uncertainties are presented for integrated gluon-gluon and gluon-quark lumino… more
Date: July 1, 1998
Creator: Huston, J., FERMI
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Theoretical description of heavy quark production in DIS

Description: We present results from a new event-generator Monte Carlo program for semi- inclusive DIS heavy quark production computed in a composite 3-flavor/4-flavor scheme, which is applicable over a wider range of energy scales than existing calculations. We compare the semi-inclusive distributions in p{sub t}, Q{sup 2} and W at O ({alpha}{sup 1}{sub s}) with recent HERA results. We also compare the inclusive F{sup charm}{sub 2} with the data and the existing O ({alpha}{sup 2}{sub s}) 3-flavor scheme ca… more
Date: July 1, 1998
Creator: Amundson, J., FERMI
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Synergistic approach to modeling X-ray spectra

Description: Plasma emission models used in X-ray astronomy need to simulate X-ray spectra from at least thirteen elements. Development of comprehensive models requires large-scale calculations; for example, Fe M-shell spectra, K{alpha} fluorescence from near-neutral ions, and dielectronic recombination satellite spectra from L-shell ions. Current and recent missions (EUVE, ASCA, DXS, etc.) have already demonstrated the need for major, rapid improvements in spectral models. The high-resolution spectra to be… more
Date: July 1, 1998
Creator: Liedahl, D.A., LLNL
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Observation of Z decays to b quark pairs at the Tevatron Collider

Description: A search for Z boson decays to pairs of b-quark jets has been performed in the full dataset collected with the CDF detector at the Tevatron p{anti p} collider. After the selection of a pure sample of b {anti b} events by means of the identification of secondary vertices from b-quark decays, we have used two kinematic variables to further discriminate the electroweak b {anti b} production from QCD processes, and sought evidence for the Z decay in the dijet invariant mass distribution. An absolut… more
Date: July 1, 1998
Creator: Dorigo, T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Measurements of the longitudinal structure function and |V{sub cs}| in the CCFR experiment

Description: Measurements of charged current neutrino and anti-neutrino nucleon interactions in the CCFR detector are used to extract the structure functions, F{sub 2}, xF{sub 3}{sup {nu}} , xF{sub 3}{sup {anti {nu}}} and R(longitudinal) in the kinematic region 0.01 < x < 0.6 and 1 < Q{sup 2} < 300 GeV{sup 2}. The new measurements of R in the x < 0.1 region provide a constraint on the level of the gluon distribution. The x and Q{sup 2} dependence of R is compared with a QCD based fit to previous data. The C… more
Date: July 1, 1998
Creator: Yang, U.K.
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Partner: UNT Libraries Government Documents Department
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Particle size distribution of dust collected from Alcator C-MOD

Description: There are important safety issues associated with tokamak dust, accumulated primarily from sputtering and disruptions. The dust may contain tritium, it may be activated, chemically toxic, and chemically reactive. The purpose of this paper is to present results from analyses of particulate collected from the Alcator C-MOD tokamak located at Massachusetts Institute of Technology (MIT) in Cambridge, Massachusetts. The sample obtained from C-MOD was not originally intended for examination outside o… more
Date: July 1, 1998
Creator: Gorman, S.V.; Carmack, W.J. & Hembree, P.B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Helical spin-density wave in Fe/Cr trilayers with perfect interfaces

Description: Despite the presence of only collinear, commensurate (C) and incommensurate (I) spin-density waves (SDW`s) in bulk Cr, the interfacial steps in Fe/Cr multilayers are now believed to stabilize a helical (H) SDW within the Cr spacer. Yet H SDW`s were first predicted in an Fe/Cr trilayer with perfect interfaces when the orientation of the Fe moments does not favor C ordering: if the number of Cr monolayers is even (odd) and the Fe moments are pointing in the same (opposite) direction, then a C SDW… more
Date: July 1, 1998
Creator: Fishman, R.S.
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Partner: UNT Libraries Government Documents Department
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Masses of orbitally excited baryons in large N{sub c} QCD

Description: The authors present the first phenomenological study of the masses of orbitally excited baryons in large N{sub c} QCD. Restricting here to the nonstrange sector of the L=1 baryons, the 1/N{sub c} expansion is used to order and select a basis of effective operators that spans the nine observables (seven masses and two mixing angles). Fits are performed using subsets of the complete set of nine operators, including corrections up to O(1/N{sub c}) where leading order is N{sub c}{sup 1}. This study… more
Date: July 1, 1998
Creator: Carlson, Carl E.; Carone, Christopher D.; Goity, Jose' L. & Lebed, Richard F.
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Partner: UNT Libraries Government Documents Department
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Factorization for high-energy scattering

Description: The author demonstrates that the amplitude of the high-energy scattering can be factorized in a product of two independent functional integrals over ''fast'' and ''slow'' fields which interact by means of Wilson-line operators -- gauge factors ordered along the straight lines.
Date: July 1, 1998
Creator: Balitsky, Ian
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Partner: UNT Libraries Government Documents Department
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Gamma-ray burst spectra and time histories from 2 to 400 keV

Description: The Gamma-Ray burst detector on Ginga consisted of a proportional counter to observe the x-rays and a scintillation counter to observe the gamma-rays. Both instrument recorded the time histories in phase with each other and with 0.03125 s temporal resolution. The author compares the average of 21 gamma-ray bursts to determine the delay, in any, between the peak of the x-rays and the peak of the gamma-rays. The delay is less than or about equal to 30 msec. Thus, models must content with two aver… more
Date: July 1, 1998
Creator: Fenimore, E.E.
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Partner: UNT Libraries Government Documents Department
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New Monte Carlo simulations of the LLNL pulsed-sphere experiments

Description: From the late 1960s to about 1985, the Pulsed-Sphere Program at Lawrence Livermore National Laboratory (LLNL) was carried out to measure 14-MeV neutron leakage spectra from target spheres made out of various elements, compounds, and mixtures Data from these experiments have been and continue to be fundamental in the evaluation of neutron Monte Carlo transport codes and cross section data libraries In addition, the data provide important integral information for stockpile stewardship, fusion tec… more
Date: July 1, 1998
Creator: Marchetti, A.A., LLNL
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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