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Search for the Higgs Boson and Technicolor Particles in p anti-p Colisions at sqrt(s) = 1.8 TeV

Description: In the Standard Model (SM) of the elementary particles, the interactions among the known fundamental fermions (leptons and quarks) are mediated through gauge bosons which obey the symmetry: SU(3) {circle_times} SU(2) {circle_times} U(1). More precisely, the electroweak interaction [4-6] is described by a gauge symmetry SU(2) {circle_times} U(1) which is broken spontaneously. The electroweak symmetry breaking is implemented by the introduction of a complex scalar Higgs field which has a non-zero… more
Date: November 1, 1999
Creator: Cortabitarte, Rocio Vilar & /Cantabria U., Santander
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
open access

Review of ENDF/B-VI Fission-Product Cross Section

Description: In response to concerns raised in the Defense Nuclear Facilities Safety Board (DNFSB) Recommendation 93-2, the U.S. Department of Energy (DOE) developed a comprehensive program to help assure that the DOE maintain and enhance its capability to predict the criticality of systems throughout the complex. Tasks developed to implement the response to DNFSB recommendation 93-2 included Critical Experiments, Criticality Benchmarks, Training, Analytical Methods, and Nuclear Data. The Nuclear Data Task … more
Date: January 1, 1999
Creator: Wright, R.Q.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Novel Analytical Techniques Based on an Enhanced Electron Attachment Process

Description: Sensitive and selective detection of dense non-aqueous liquids (DNAPL), volatile organic compounds (VOC), and other organics, such as polychlorinated biphenyls (PCB), is an area of importance to the DOE's environmental restoration program. Current negative-ion based analytical methods for the detection of these compounds rely on their propensity to form negative ions (in their ground electronic states). However, for compounds with smaller electron capture cross sections, including PCBs with few… more
Date: June 1, 1999
Creator: Pinnaduwage, Lal A. & Buchanan, Michelle V.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Development of a High Fluence Neutron Source for Nondestructive Characterization of Nuclear Waste

Description: We are addressing the need to measure nuclear wastes, residues, and spent fuel in order to process these for final disposition. For example, TRU wastes destined for the WIPP must satisfy extensive characterization criteria outlined in the Waste Acceptance Criteria, the Quality Assurance Program Plan, and the Performance Demonstration Plan. Similar requirements exist for spent fuel and residues. At present, no nondestructive assay (NDA) instrumentation is capable of satisfying all of the PDP tes… more
Date: December 31, 1999
Creator: Pickrell, Mark M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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RESERVOIR CHARACTERIZATION OF THE LOWER GREEN RIVER FORMATION, SOUTHWEST UINTA BASIN, UTAH

Description: The +2000-foot-thick (600-m), Tertiary-aged lacustrine deposits of the Middle and Lower Members of the Green River Formation contain the primary oil-producing reservoirs in the southwest Uinta Basin. The authors developed a log-based correlation scheme by identifying what they interpret as depositional cycles on the gamma-ray and resistivity logs of several wells. Regional cross sections were constructed and cycle boundaries revised as needed. The cycles typically range from 50 to 100 feet (15-… more
Date: August 17, 1999
Creator: Morgan, C.D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Review of Subcritical Source-Driven Noise Analysis Measurements

Description: Subcritical source-driven noise measurements are simultaneous Rossi-{alpha} and randomly pulsed neutron measurements that provide measured quantities that can be related to the subcritical neutron multiplication factor. In fact, subcritical source-driven noise measurements should be performed in lieu of Rossi-{alpha} measurements because of the additional information that is obtained from noise measurements such as the spectral ratio and the coherence functions. The basic understanding of sourc… more
Date: November 24, 1999
Creator: Valentine, T.E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Validation of KENO V.a Comparison with Critical Experiments

Description: Section 1 of this report documents the validation of KENO V.a against 258 critical experiments. Experiments considered were primarily high or low enriched uranium systems. The results indicate that the KENO V.a Monte Carlo Criticality Program accurately calculates a broad range of critical experiments. A substantial number of the calculations showed a positive or negative bias in excess of 1 1/2% in k-effective (k{sub eff}). Classes of criticals which show a bias include 3% enriched green block… more
Date: January 1, 1999
Creator: Jordan, W. C.; Landers, N. F. & Petrie, L. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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High Accuracy, High Energy He-Erd Analysis of H,C, and T

Description: A new analysis technique using high-energy helium ions for the simultaneous elastic recoil detection of all three hydrogen isotopes in metal hydride systems extending to depths of several {micro}m's is presented. Analysis shows that it is possible to separate each hydrogen isotope in a heavy matrix such as erbium to depths of 5 {micro}m using incident 11.48MeV {sup 4}He{sup 2} ions with a detection system composed of a range foil and {Delta}E-E telescope detector. Newly measured cross sections … more
Date: July 22, 1999
Creator: Browning, James F.; Langley, Robert A.; Doyle, Barney L.; Banks, James C. & Wampler, William R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A Large Neutrino Detector Facility at the Spallation Neutron Source at Oak Ridge National Laboratory

Description: The ORLaND (Oak Ridge Large Neutrino Detector) collaboration proposes to construct a large neutrino detector in an underground experimental hall adjacent to the first target station of the Spallation Neutron Source (SNS) at the Oak Ridge National Laboratory. The main mission of a large (2000 ton) Scintillation-Cherenkov detector is to measure {bar {nu}}{sub {mu}} {r_arrow} {bar {nu}}{sub e} neutrino oscillation parameters more accurately than they can be determined in other experiments, or sign… more
Date: February 14, 1999
Creator: Efremenko, Y.V.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Measurement of the triple differential jet cross section at {square root} s = 1800 GeV

Description: We present a measurement of the triple differential cross section for dijet production in proton-antiproton scattering at a center of mass energy of 1800 GeV. The data were taken with the D0 detector at the Fermilab Tevatron and are compared to next to leading order QCD theoretical predictions with differing parton distribution functions. The data are of sufficient accuracy to rule out or favor parton distribution functions over a wide range in x .
Date: July 7, 1999
Creator: Schellman, H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A Preliminary Calculation of 235U (n,2n) 234U Cross Sections

Description: Preliminary calculations of the total two-neutron emission cross section, {sup 235}U(n,2n) {sup 234}U and the partial two-neutron emission cross sections, {sup 235}U(n, 2n{gamma}) {sup 234}U, are presented. The {sup 235}U(n, 2n{gamma}) {sup 234}U cross sections describe the process of {gamma}-decays in the residual nucleus following the two-neutron emission and were calculated for several {gamma}-transitions between states of the ground-state band of the {sup 234}U nucleus. All three reaction m… more
Date: November 23, 1999
Creator: Chen, H.; Ross, M.A.; Reffo, G.; White, R.M. & Younes, W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Spin measurements in high -t exclusive photoreactions

Description: The approximate validity of the constituent counting rules to few GeV photoreactions has been known for many years. It is now generally accepted that perturbative QCD, which leads to these rules, cannot be applicable in this low energy and momentum transfer regime. Cross section and polarization measurements now underway show promise to lead to the underlying physics. Initial experiments on deuteron photodisintegration and pion electroproduction are now in progress, and are expected to be follo… more
Date: May 1, 1999
Creator: Gilman, Ron
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Tevatron Direct Photon Results

Description: Tevatron direct photon results since DIS98 are reviewed. Two new CDF measurements are discussed, the Run Ib inclusive photon cross section and the photon+muon cross section. Comparisons with the latest NLO QCD calculations are presented.
Date: July 20, 1999
Creator: Kuhlmann, S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Self-Adjoint Angular Flux Equation for Coupled Electron-Photon Transport

Description: Recently, Morel and McGhee described an alternate second-order form of the transport equation called the self adjoint angular flux (SAAF) equation that has the angular flux as its unknown. The SAAF formulation has all the advantages of the traditional even- and odd-parity self-adjoint equations, with the added advantages that it yields the full angular flux when it is numerically solved, it is significantly easier to implement reflective and reflective-like boundary conditions, and in the appro… more
Date: July 8, 1999
Creator: Liscum-Powell, J. L.; Lorence, L. J., Jr.; Morel, J. E. & Prinja, A. K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Quantitative Analysis with Heavy Ion E-TOF ERD

Description: Heavy ion TOF ERD combined with energy detection (E-TOF-ERD) is a powerful analytical technique taking advantage of the following facts: the scattering cross section is usually very high ({approximately}10{sup {minus}21} cm{sup 2}/sr) compared to regular He RBS ({approximately}10{sup {minus}25} cm{sup 2}/sr), contrary to what happens with the energy resolution in ordinary surface solid barrier detectors, time resolution is almost independent of the atomic mass of the detected element, and the d… more
Date: July 23, 1999
Creator: Banks, J.C.; Doyle, B.L. & Font, A. Climent
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Distinguishing Indirect Signatures Arising From New Physics at the NLC

Description: Many sources of new physics can lead to shifts in the Standard Model predictions for cross sections and asymmetries at the NLC below their direct production thresholds. In this talk we discuss some of the tools that are useful for distinguishing amongst these new physics scenarios. R-parity violation and extensions of the Standard Model gauge structure are two typical non-minimal realizations of supersymmetry which provide us with an important test case to examine.
Date: July 14, 1999
Creator: Rizzo, Thomas G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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{gamma}{gamma} {r_arrow} {gamma}{gamma} as a Test of Weak Scale Quantum Gravity at the NLC

Description: Recently, it has been proposed that the fundamental scale of quantum gravity can be close to the weak scale if there are large extra dimensions . This proposal has important phenomenological implications for processes at the TeV scale. We study the process {gamma}{gamma} {r_arrow} {gamma}{gamma}, assuming an ultraviolet cutoff M{sub S} {approximately} 1 TeV for the effective gravity theory. We find that, at center of mass energies {radical}s {approximately} 1 TeV, the contribution of gravitatio… more
Date: April 23, 1999
Creator: Davoudiasl, Hooman
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Top quark physics at the Tevatron

Description: The authors present the recent results and future prospects on top quark physics at the Tevatron. They describe the measurements of the top quark mass and the search for single top quark production in 1.8-TeV p{bar p} collisions. The CDF and D0 combined results yield a top quark mass of 174.3 {+-} 5.1 GeV/c{sup 2}. The upper limit at 95% C.L. of the single top production cross section is found to be 16.0 pb and 15.6 pb for the W-gluon fusion process and s-channel W* process, respectively.
Date: October 7, 1999
Creator: Kim, S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Precise tests of x-ray scattering theories in the Compton regime.

Description: The authors report two experiments intended to test the accuracy of state-of-the-art theoretical predictions for x-ray scattering from low-Z atoms. The first one deals with the differential x-ray scattering cross sections in Ne and He from 11-22 keV and the Ne Compton-to-Rayleigh scattering ratio in this energy range. It was found that, in order to be consistent with the experimental results, an accurate description at low Z must include nonlocal exchange, electron correlation, and dynamic effe… more
Date: January 15, 1999
Creator: Dunford, R. W.; Gemmell, D. S.; Kanter, E. P.; Krassig, B.; Southworth, S. H. & Young, L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Radiation Shielding for Fusion Reactors

Description: Radiation shielding requirements for fusion reactors present different problems than those for fission reactors and accelerators. Fusion devices, particularly tokamak reactors, are complicated by geometry constraints that complicate disposition of fully effective shielding. This paper reviews some of these shielding issues and suggested solutions for optimizing the machine and biological shielding. Radiation transport calculations are essential for predicting and confirming the nuclear performa… more
Date: October 1, 1999
Creator: Santoro, R. T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Vector Boson Pair Production in Hadronic Collisions at Order alpha(s): Lepton Correlations and Anomalous Couplings

Description: We present cross sections for production of electroweak vector boson pairs, WW, WZ and ZZ, in p{bar p} and pp collisions, at next-to-leading order in {alpha}{sub s}. We treat the leptonic decays of the bosons in the narrow-width approximation, but retain all spin information via decay angle correlations. We also include the effects of WWZ and WW{gamma} anomalous couplings.
Date: July 13, 1999
Creator: Dixon, Lance
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Probing excited states in nuclei at and beyond the proton dripline.

Description: The coupling of a Compton-suppressed Ge (CSGe) detector array to a recoil separator has seen limited use in the past due to the low efficiency for measuring recoil--{gamma} ray coincidences (< 0.1%). With the building of new generation recoil separators and gamma-ray arrays, a substantial increase in detection efficiency has been achieved. This allows for the opportunity to measure excited states in nuclei with cross-sections below 100 nb. In this paper, results from the coupling of a modest… more
Date: March 15, 1999
Creator: Carpenter, M. P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Inclusive jet production and subjets at the Tevatron

Description: The D0 and CDF proton-antiproton collider experiments at the Tevatron accumulated large samples of high energy jet production data during Run I (1992- 1996). Presented here are measurements of the central inclusive jet cross section at center-of-mass energies of 1800 and 630 GeV (by the D0 and CDF experiments) and a forward ( |{eta}| < 1.5) inclusive cross section measurement by the D0 experiment at 1800 GeV. Cross sections are compared to next-to-leading order QCD predictions with recent parto… more
Date: October 26, 1999
Creator: Gallas, E.J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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