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Relativistic heavy ion physics

Description: In the fall of 1986, beams of heavy ions up to A = 40 at total energies up to E = 225 GeV/nucleon will become available for experiments at CERN (60 and 225 GeV/nucleon) and at Brookhaven (15.5 GeV/nucleon). Future experiments to look for quark confinement are discussed. 9 refs., 3 figs. (GHT)
Date: January 1, 1985
Creator: Hansen, O.
Partner: UNT Libraries Government Documents Department
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Trends in nuclear spectroscopy with (more or less) direct reactions

Description: Recent experiments on the Gamow-Teller giant resonance are discussed with special regard to the strength sum rules. Some ideas for further investigations of pairing collective modes are presented. The emphasis is on one fermion-two boson states and on two boson transfer reactions. Finally some new experimental results from heavy ion inelastic scattering are presented and the role of such processes in the energy ion mechanisms leading to deep inelastic collisions is discussed.
Date: January 1, 1981
Creator: Hansen, O.
Partner: UNT Libraries Government Documents Department
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Strangeness production in Si + Au interactions at 14. 6 GeV/c per nucleon

Description: Production of strange particles in proton-proton interactions is systematically suppressed relative to the production of non-strange particles. A first order goal of experiments on strangeness production in nucleus-nucleus collisions is to find out if strangeness is suppressed in a way similar to the p-p interactions or whether the nuclear environment changes the behaviour. This paper investigates this possibility. 13 refs., 1 tab.
Date: January 1, 1989
Creator: Hansen, O.
Partner: UNT Libraries Government Documents Department
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Nucleus-nucleus collisions at very high energies

Description: The present report covers the material of two lectures. The first part, contains a collection of useful formulae from relativistic kinematics and deals with invariant cross sections and multiplicities. The remainder of the paper is on strangeness production in relativistic heavy ion collisions. Some elementary rules for particle production in nucleon-nucleon interactions are presented. This paper also contains arguments on why one expects enhanced strange particle production from the quark-gluo… more
Date: January 1, 1990
Creator: Hansen, O.
Partner: UNT Libraries Government Documents Department
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Quasielastic reactions

Description: A brief review is presented of the experimental and theoretical situation regarding transfer reactions and inelastic scattering. In the first category there is little (very little) precision data for heavy projectiles and consequently almost no experience with quantitative theoretical analysis. For the inelastic scattering the rather extensive data strongly supports the coupled channels models with collective formfactors. At the most back angles, at intensities about 10/sup -5/ of Rutherford sc… more
Date: January 1, 1983
Creator: Hansen, O.
Partner: UNT Libraries Government Documents Department
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Strangeness enhancement in 14. 6 A GeV/c Si+Au interactions

Description: The questions of strangeness enhancement and of J/{psi} suppression have become central in the discussion of high energy heavy ion physics. Both phenomena have been predicted as signs of the formation of a deconfined quark-gluon phase of matter, both have been observed and both may be explainable also in terms of ordinary hadronic matter. In this note the question of K{sup +} and K{sup {minus}} enhancement will be discussed from a much less elevated point of view, namely as a question of enhanc… more
Date: January 1, 1990
Creator: Hansen, O.
Partner: UNT Libraries Government Documents Department
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Neutron scattering analysis with microscopic optical model potentials

Description: A review of microscopic optical model potentials used in the analysis of neutron scattering and analyzing power data below 100 MeV (5 {le}E{sub n}{le}100 MeV) is presented. The quality of the fits to the data over a wide massd ({sup 6}Li-{sup 239}Pu) and energy range is discussed. It is shown that reasonably good agreement with the data is obtained with only three parameters, {lambda}{sub V}, {lambda}{sub W}, and {lambda}{sub SO}, which show a smooth mass and energy dependence. These parameters… more
Date: September 3, 1991
Creator: Hansen, L. F.
Partner: UNT Libraries Government Documents Department
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14 MeV neutron work at the Lawrence Livermore National Laboratory

Description: The 14 MeV neutron work at Lawrence Livermore National Laboratory (LLNL) covers two main areas of interest to this Symposium: (1) measurements and calculations of differential cross sections; and (2) integral measurements of the neutron and gamma emission spectra. In both areas a large number of materials have been studied, spanning a wide mass range (6 < A < 239), of interest to fusion and hybrid reactors. In this presentation a brief description of the experimental techniques and calculationa… more
Date: July 1, 1985
Creator: Hansen, L. F.
Partner: UNT Libraries Government Documents Department
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Study of proton-induced reactions and correlation with fast-neutron scattering

Description: The generation of cross sections for fast neutron-nucleon interactions obtained from elastic and charge-exchange proton data is discussed in terms of the Lane model formalism. A general description of the interaction of nucleons with nuclei is presented in terms of the optical model and the extended (or coupled-channel) optical model, together with the relation of these models to microscopic calculations of the nucleon-nucleon interaction. Comparisons between neutron elastic data and calculatio… more
Date: January 19, 1982
Creator: Hansen, L. F.
Partner: UNT Libraries Government Documents Department
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Measurements and calculations of neutron scattering angular distributions over a wide mass and energy range

Description: Neutron elastic and inelastic differential cross sections for targets between /sup 9/Be and /sup 239/Pu at energies, E > 14 MeV have been measured using the Livermore and Ohio University neutron time-of-flight facilities. We review here the data and the analyses based on two local microscopic optical potentials: that of Jeukenne, Lejeune and Mahaux, and that of Brieva and Rook. The results are also compared with calculations using global potentials. Coupled channel formalism has been used in th… more
Date: May 1, 1985
Creator: Hansen, Luisa F.
Partner: UNT Libraries Government Documents Department
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Rossi Alpha Method

Description: The Rossi Alpha Method has proved to be valuable for the determination of prompt neutron lifetimes in fissile assemblies having known reproduction numbers at or near delayed critical. This workshop report emphasizes the pioneering applications of the method by Dr. John D. Orndoff to fast-neutron critical assemblies at Los Alamos. The value of the method appears to disappear for subcritical systems where the Rossi-..alpha.. is no longer an ..alpha..-eigenvalue.
Date: January 1, 1985
Creator: Hansen, G. E.
Partner: UNT Libraries Government Documents Department
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Integral measurements and calculations of neutron and gamma-ray emission at 14 MeV and an overview of the new multi-user tandem at LLNL

Description: In this paper two topics will be presented: (a) the integral measurements and calculations of gamma-ray and neutron emission spectra due to a source of 14 MeV neutrons from materials of interest to thermonuclear reactors and (b) an overview of the new multi-user accelerator facility being built at LLNL. Under (a), recent measurements of the gamma-ray and neutron leakage spectra from materials ranging from Be to /sup 238/U pulsed with 14 MeV neutrons are presented. The Monte Carlo calculational … more
Date: August 1, 1987
Creator: Hansen, L. F.
Partner: UNT Libraries Government Documents Department
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Studies of Nucleon Form Factors with 12 GeV CEBAF and SuperBigBite

Description: The elastic electromagnetic form factors are among the most fundamental quantities that describe the ground-state structure of the proton and neutron. Precision data of the form factors over a wide kinematical range provide a powerful test of current theories of hadron structure. A number of experiments aiming to measure the electric and magnetic elastic form factors of the neutron, G{sub E}{sup n} and G{sub M}{sup n}, and proton, G{sub E}{sup p}, at very high momentum transfer, up to the range… more
Date: April 1, 2012
Creator: Hansen, Jens-Ole
Partner: UNT Libraries Government Documents Department
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Gothic Model of BWR Secondary Containment Drawdown Analyses

Description: This article introduces a GOTHIC version 7.1 model of the Secondary Containment Reactor Building Post LOCA drawdown analysis for a BWR. GOTHIC is an EPRI sponsored thermal hydraulic code. This analysis is required by the Utility to demonstrate an ability to restore and maintain the Secondary Containment Reactor Building negative pressure condition. The technical and regulatory issues associated with this modeling are presented. The analysis includes the affect of wind, elevation and thermal imp… more
Date: October 6, 2004
Creator: Hansen, Paul N.
Partner: UNT Libraries Government Documents Department
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A comparison of the shielding performances of the AT-400A, Model FL and Model AL-R8 containers

Description: A comparison of the neutron and photon dose rates at different locations on the outside surface of the Model AL-RB, Model FL and the AT-400A containers for a given pit load has been done in order to understand the shielding characteristics of these containers. The Model AL-R8 is not certified for transport and is only used for storage of pits, while the Model FL is a certified Type B pit transportation container. The AT-400A is being developed as a type B pit storage and transportation containe… more
Date: April 28, 1995
Creator: Hansen, L. F.
Partner: UNT Libraries Government Documents Department
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Analog fiber optic multiplexing techniques and results from the Hunters Trophy Experiment

Description: Due to the growth in the use of analog fiber optic data transmission systems at the Nevada Test Site and other locations, Sandia National Laboratories (SNL) has recognized the need to be able to multiplex several data channels per fiber. Wavelength-division, frequency-division, and time-division multiplex techniques have been investigated. A time-division system using optically-multiplexed laser transmitters driving a common receiver was fielded on the HUNTERS TROPHY event at the NTS. Stability… more
Date: November 1, 1993
Creator: Hansen, G. J.
Partner: UNT Libraries Government Documents Department
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Shielding requirements for the transport of nuclear warhead components under decommissioning

Description: The requirements to carry out accurate shielding calculations involved with the safe off-site transportation of packages containing nuclear warhead components, special assemblies and radioactive materials are discussed. The need for (a) detailed information on the geometry and material composition of the packaging and radioactive load, (b) accurate representation of the differential energy spectra (dN/dE) for the neutron and gamma spectra emitted by the radioactive materials enclosed in the pac… more
Date: September 1, 1994
Creator: Hansen, L. F.
Partner: UNT Libraries Government Documents Department
open access

{sup 3}He[pol]({rvec e}, e{prime})X and the neutron electromagnetic form factors

Description: Recent data for the spin-dependent A{sub T}, and A{sub TL}, asymmetries in {sup 3}He[pol]({rvec e}, e{prime}) quasielastic scattering are reviewed. The neutron electric and magnetic form factors are extracted from the data using a plane wave impulse approximation (PWIA) model, and the model uncertainties are estimated. The extracted G{sub M}{sup n} is in agreement with the dipole prediction as well as with other recent experiments. No meaningful result for G{sub E}{sup n} is obtained due to lar… more
Date: December 31, 1995
Creator: Hansen, J.O.
Partner: UNT Libraries Government Documents Department
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Key Geomechanics Issues at the Waste Isolation Pilot Plant Geomechanics

Description: Mechanical and hydrological properties of rock salt provide excellent bases for geological isolation of hazardous materials. Regulatory compliance determinations for the Waste Isolation Pilot Plant (WIPP) stand as testament to the widely held conclusion that salt provides excellent isolation properties. The WIPP saga began in the 1950s when the U.S. National Academy of Sciences (NAS) recommended a salt vault as a promising solution to the national problem of nuclear waste disposal. For over 20 … more
Date: September 1, 1999
Creator: Hansen, Francis D.
Partner: UNT Libraries Government Documents Department
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Streamlining the process: A strategy for making NEPA work better and cost less

Description: When the National Environmental Policy Act (NEPA) was enacted in 1969, neither Congress nor the Federal Agencies affected anticipated that implementation of the NEPA process would result in the intolerable delays, inefficiencies, duplication of effort, commitments of excessive financial and personnel resources, and bureaucratic gridlock that have become institutionalized. The 1975 Council on Environmental Quality (CEQ) regulations, which were intended to make the NEPA process more efficient and… more
Date: May 1, 1998
Creator: Hansen, R.P.; Hansen, J.D. & Wolff, T.A.
Partner: UNT Libraries Government Documents Department
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Geometric optimization

Description: An algorithm is presented which describes an application independent method for reducing the number of polygonal primitives required to faithfully represent an object. Reducing polygon count without a corresponding reduction in object detail is important for: achieving interactive frame rates in scientific visualization, reducing mass storage requirements, and facilitating the transmission of large, multi-timestep geometric data sets. This paper shows how coplanar and nearly coplanar polygons c… more
Date: September 1, 1993
Creator: Hinker, P. & Hansen, C.
Partner: UNT Libraries Government Documents Department
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Combined plate motion and density driven flow in the asthenosphere beneath Saudi Arabia: Evidence from shear-wave splitting and seismic anisotropy

Description: A comprehensive study of mantle anisotropy along the Red Sea and across Saudi Arabia was performed by analyzing shear-wave splitting recorded by stations from three different seismic networks: the largest, most widely distributed array of stations examined across Saudi Arabia to date. Stations near the Gulf of Aqaba display fast orientations that are aligned parallel to the Dead Sea Transform Fault, most likely related to the strike-slip motion between Africa and Arabia. However, most of our ob… more
Date: February 8, 2006
Creator: Hansen, S & Schwartz, S
Partner: UNT Libraries Government Documents Department
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ADMINISTRATIVE AND ENGINEERING CONTROLS FOR THE OPERATION OF VENTILATION SYSTEMS FOR UNDERGROUND RADIOACTIVE WASTE STORAGE TANKS

Description: Liquid radioactive wastes from the Savannah River Site are stored in large underground carbon steel tanks. The majority of the waste is confined in double shell tanks, which have a primary shell, where the waste is stored, and a secondary shell, which creates an annular region between the two shells, that provides secondary containment and leak detection capabilities should leakage from the primary shell occur. Each of the DST is equipped with a purge ventilation system for the interior of the … more
Date: November 13, 2013
Creator: Wiersma, B. & Hansen, A.
Partner: UNT Libraries Government Documents Department
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