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A Search for New Leptons with Heavy Neutrinos in e/sup +/e/sup -/ Annihilation at. sqrt. s = 29 GeV. [None]

Description: This thesis describes the results of a search for new leptons with associated heavy neutrinos. The search uses 68.1 pb/sup /minus/1/ of data taken with the TPC2..gamma.. detector at the PEP storage ring. New lepton pairs with charged lepton masses m/sub L/ < 12 GeV and mass differences in the approximate range 0.4 GeV < m/sub L/ /minus/ m/sub/nu/L/ < 2.5 GeV are excluded at the 99% confidence level. Results are also given of a study of search techniques for the region m/sub L/ < 12 GeV, m/sub L… more
Date: May 5, 1988
Creator: Mathis, L. G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Recent developments in nuclear reaction theories and calculations

Description: A brief review is given of some recent developments in the fields of optical model potentials; level densities; and statistical model, precompound, and direct reaction codes and calculations. Significant developments have occurred in all of these fields since the 1977 Conference on Neutron Cross Sections, which will greatly enhance the ability to calculate high-energy neutron-induced reaction cross sections in the next few years. 11 figures, 3 tables.
Date: May 5, 1980
Creator: Gardner, D. G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A systematic study of J/psi suppression in cold nuclear matter

Description: Understanding the effects of cold nuclear matter on J/psi production is a key requirement in order to interpret the J/psi suppression reported in heavy-ion collisions. Based on a Glauber model, the J/psi-nucleon inelastic cross section is determined from a statistical analysis of J/psi world data on nuclear targets. The global fit of all data gives sigmaJ/psiN = 3.4 +/- 0.2 mb, significantly smaller than previous estimates, yet the chi2 of the fit is pretty large, chi2/ndf = 1.5. A similar valu… more
Date: April 5, 2008
Creator: Arleo, Francois & Tram, Vi-Nham
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Results of groundwater monitoring at Everest, Kansas, in April 2008.

Description: On September 7, 2005, the Commodity Credit Corporation of the U.S. Department of Agriculture (CCC/USDA) presented a Scoping Memo (Argonne 2005) for preliminary consideration by the Kansas Department of Health and Environment (KDHE), suggesting possible remedial options for the carbon tetrachloride contamination in groundwater at Everest, Kansas. The suggested approaches were discussed by representatives of the KDHE, the CCC/USDA, and Argonne at the KDHE office in Topeka on September 8-9, 2005, … more
Date: November 5, 2008
Creator: LaFreniere, L. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Modeling of High Precision Neutron Nonelastic Cross Sections

Description: A new method has been applied to the determination of neutron nonelastic cross sections for iron {sup 56}Fe and lead {sup 208}Pb for energies between 5 and 26 MeV. These data have estimated errors of only a few percent and do not suffer from the ambiguities encountered in earlier nonelastic data. We attempt to fit these high precision data using both a semiclassical single phase shift model (nuclear Ramsauer model) as well as a recent global optical model that well reproduces a wide body of neu… more
Date: February 5, 2007
Creator: Dietrich, F. S.; Anderson, J. D.; Bauer, R. W.; Grimes, S. M. & McNabb, D. P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Total cross sections and elastic scattering at the SSC

Description: The need is discussed of a special purpose detector for the measurement of elastic scattering at the SSC. The detector would cover as small a solid angle as is practical. Two techniques are described briefly to measure total cross sections at hadron storage rings. The direct method is to measure the interaction rate in an IR of known luminosity - a method that gets more difficult increasing energy. A second method is to use the optical theorem. 6 refs., 1 fig. (LEW)
Date: December 5, 1985
Creator: Foley, K.J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Some limitations of detailed balance for inverse reaction calculations in the astrophysical p-process

Description: p-Process modeling of some rare but stable proton-rich nuclei requires knowledge of a variety of neutron, charged particle, and photonuclear reaction rates at temperatures of 2 to 3 {times} 10{sup 9} {degrees}K. Detailed balance is usually invoked to obtain the stellar photonuclear rates, in spite of a number of well-known constraints. In this work we attempt to calculate directly the stellar rates for ({gamma},n) and ({gamma},{alpha}) reactions on {sup 151}Eu. These are compared with stellar r… more
Date: December 5, 1990
Creator: Gardner, D. G. & Gardner, M. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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First measurement of the left-right cross section asymmetry in Z boson production at E{sub cm} = 91.5 GeV

Description: The left-right cross section asymmetry for Z boson production in e{sup +} e{sup {minus}} annihilation (A{sub LR}) is being measured at E{sub cm} 91.5 GeV with the SLD detector at the SLAC Linear Collider (SLC) using a longitudinally polarized electron beam. The electron polarization is continually monitored with a Compton scattering polarimeter, and is typically 22%. At the current time, we have accumulated a sample of 4779 Z events. We find that A{sub LR} = 0.02 {double_bond} 0.07 {doteq} 0.00… more
Date: August 5, 1992
Creator: Collaboration, SLD
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Status of {alpha}{sub s} measurements

Description: I review the current determinations of {alpha}{sub s}. Attention is given to the theoretical uncertainties inherent in most determinations. all current determinations are consistent with an average of {alpha}{sub s}(M{sub Z}) = 0.119{plus_minus}0.005. Prospects for reduction of the errors in the future are discussed.
Date: May 5, 1993
Creator: Hinchliffe, I.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Experimental study of interactions of highly charged ions with atoms at keV energies. Progress report, July 1, 1991--June 30, 1992

Description: This Progress Report describes the experimental work carried out, and the work in progress, at the Cornell EBIS Laboratory during the period 7/1/1991 to 6/30/1992. During this period, a number of experiments were carried out. The absolute values of the total, one, two and three electron transfer cross sections for highly charged argon ions (8{le}q{le}16) colliding with argon at 2.3 qkev laboratory energy were measured. The distribution of recoil ions and molecular fragments formed in highly cha… more
Date: July 5, 1992
Creator: Kostroun, V. O.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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D-Zero Collison Hall Ventilation Measurements

Description: This engineering note documents air velocity measurements taken on September 5, 2002 for the D-Zero collision hall. These measurements were done after changes were made to the building dampers, DM-1, DM-2, and DM-14 such that the collision hall would be at a slight positive pressure. Measurements were made by Pete Simon and Mike Sarychev. They systematically took velocity measurements across the duct cross sections. Their raw measurements are included.
Date: September 5, 2002
Creator: Rucinski, Russell A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Experimental study of interactions of highly charged ions with atoms at keV energies

Description: This Progress Report describes the experimental work carried out, and the work in progress, at the Cornell EBIS Laboratory during the period 7/1/1991 to 6/30/1992. During this period, a number of experiments were carried out. The absolute values of the total, one, two and three electron transfer cross sections for highly charged argon ions (8{le}q{le}16) colliding with argon at 2.3 qkev laboratory energy were measured. The distribution of recoil ions and molecular fragments formed in highly cha… more
Date: July 5, 1992
Creator: Kostroun, V. O.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Three-group NPR core flux levels

Description: In order to predict graphite damage rates for the NPE, it is necessary to have some knowledge of the neutron fluxes at various energy levels. In particular it is important to know flux levels relative to those existing where graphite samples have been irradiated experimentally. Three-group flux levels have been calculated for regions far from boundaries in the core of the NPR and of a K-reactor. The results reported here have been obtained from more detailed calculations using better cross sect… more
Date: January 5, 1960
Creator: Simpson, D. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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csr impedance due to a bend magnet of finite length with a vacuum chamber of rectangular cross section

Description: We study the impedance due to coherent synchrotron radiation (CSR) generated by a short bunch of charged particles passing through a dipole magnet of finite length in a vacuum chamber of a given cross section. Our method represents a further development of the previous studies: we decompose the electromagnetic field of the beam over the eigenmodes of the toroidal chamber and derive a system of equations for the expansion coefficients in the series. We illustrate our general method by calculatin… more
Date: June 5, 2009
Creator: Stupakov, G. & Kotelnikov, I.A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Exploring Prompt Measurement Methods for (n,2n) Cross Sections on Radioactive Targets

Description: This report summarizes a study of possible neutron detection technologies for performing prompt (n,2n) measurements on radioactive targets of the type that could be made at the Rare Isotope Accelerator (RIA). The report recommends conducting further research on high-pressure {sup 3}He gas scintillators as it is the best candidate technology. These detectors meet the requirements of a fast response time (fall times around 5-10 ns), gamma ray suppression, (all gamma rays below about 900 keV can b… more
Date: January 5, 2006
Creator: Ahle, L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Supersymmetry Parameter Analysis: SPA Convention and Project

Description: High-precision analyses of supersymmetry parameters aim atreconstructing the fundamental supersymmetric theory and its breakingmechanism. A well defined theoretical framework is needed whenhigher-order corrections are included. We propose such a scheme,Supersymmetry Parameter Analysis SPA, based on a consistent set ofconventions and input parameters. A repository for computer programs isprovided which connect parameters in different schemes and relate theLagrangian parameters to physical observ… more
Date: May 5, 2005
Creator: Hinchliffe, I. & al., et
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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SEARCHING FOR HIGGS BOSONS AND NEW PHYSICS AT HADRON COLLIDERS

Description: The objectives of research activities in particle theory are predicting the production cross section and decay branching fractions of Higgs bosons and new particles at hadron colliders, developing techniques and computer software to discover these particles and to measure their properties, and searching for new phenomena and new interactions at the Fermilab Tevatron and the CERN Large Hadron Collider. The results of our project could lead to the discovery of Higgs bosons, new particles, and sig… more
Date: September 5, 2007
Creator: Kao, Chung
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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CROSS SECTION EVALUATIONS FOR ENDF/B-VII.

Description: This is the final report of the work performed under the LANL contract on neutron cross section evaluations for ENDF/B-VII (April 2005-May 2006). The purpose of the contract was to ensure seamless integration of the LANL neutron cross section evaluations in the new ENDF/B-VII library. The following work was performed: (1) LANL evaluated data files submitted for inclusion in ENDF/B-VII were checked and, when necessary, formal formatting errors were corrected. As a consequence, ENDF checking code… more
Date: June 5, 2006
Creator: HERMAN, M.; ROCHMAN, D. & OBLOZINSKY, P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Neutron Resonance Parameters of 238U and the Calculated Cross Sections from the Reich-Moore Analysis of Experimental Data in the Neutron Energy Range from 0 keV to 20 keV

Description: The neutron resonance parameters of {sup 238}U were obtained from a SAMMY analysis of high-resolution neutron transmission measurements and high-resolution capture cross section measurements performed at the Oak Ridge Electron Linear Accelerator (ORELA) in the years 1970-1990, and from more recent transmission and capture cross section measurements performed at the Geel Linear Accelerator (GELINA). Compared with previous evaluations, the energy range for this resonance analysis was extended fro… more
Date: December 5, 2005
Creator: Derrien, H
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Optical Model and Cross Section Uncertainties

Description: Distinct minima and maxima in the neutron total cross section uncertainties were observed in model calculations using spherical optical potential. We found this oscillating structure to be a general feature of quantum mechanical wave scattering. Specifically, we analyzed neutron interaction with 56Fe from 1 keV up to 65 MeV, and investigated physical origin of the minima.We discuss their potential importance for practical applications as well as the implications for the uncertainties in total a… more
Date: October 5, 2009
Creator: Herman, M. W.; Pigni, M. T.; Dietrich, F. S. & Oblozinsky, P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Observation of pi+pi-pi+pi- photoproduction in ultraperipheral heavy-ion collisions at sqrt sNN = 200 GeV at the STAR detector

Description: We present a measurement of {pi}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -} photonuclear production in ultra-peripheral Au-Au collisions at {radical}s{sub NN} = 200 GeV from the STAR experiment. The {pi}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -} final states are observed at low transverse momentum and are accompanied by mutual nuclear excitation of the beam particles. The strong enhancement of the production cross section at low transverse momentum is consistent with coherent photoproduction. The {p… more
Date: July 5, 2010
Creator: STAR Collaboration
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Flavor structure of the nucleon as revealed at HERMES.

Description: The flavor structure of the nucleon as revealed in parton distributions (PDF's) is central to understanding the partonic structure of the nucleon. Recent data on unpolarized PDF's and their implications for the flavor-dependent quark helicity distributions are discussed. Results are presented for spin asymmetries in inclusive and semi-inclusive cross sections for production of pions, and kaons measured by the HERMES experiment in deep-inelastic scattering of polarized positrons on proton and de… more
Date: September 5, 2002
Creator: Jackson, H. E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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K (transverse) jet algorithms in hadron colliders: The D0 experience

Description: D0 has implemented and studied a k{sub {perpendicular}} jet algorithm for the first time in a hadron collider. The authors have submitted two physics results for publication: the subjet multiplicity in quark and gluon jets and the central inclusive jet cross section measurements. A third result, a measurement of thrust distributions in jet events, is underway. A combination of measurements using several types of algorithms and samples taken at different center-of-mass energies is desirable to u… more
Date: December 5, 2002
Creator: Elvira, V. Daniel
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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CSEWG SYMPOSIUM, A CSWEG RETROSPECTIVE. 35TH ANNIVERSARY CROSS SECTION EVALUATION WORKING GROUP, NOV. 5, 2001, BROOKHAVEN NATIONAL LABORATORY.

Description: This publication has been prepared to record some of the history of the Cross Section Evaluation Working Group (CSEWG). CSEWG is responsible for creating the evaluated nuclear data file (ENDF/B) which is widely used by scientists and engineers who are involved in the development and maintenance of applied nuclear technologies. This organization has become the model for the development of nuclear data libraries throughout the world. The data format (ENDF) has been adopted as the international st… more
Date: November 5, 2001
Creator: DUNFORD, C.; HOLDEN, N. & PEARLSTEIN, S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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