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A database of fragmentation cross section measurements applicable to cosmic ray propagation calculations

Description: A database of single particle inclusive fragment production cross section measurements has been established and is accessible over common computer networks. These measurements have been obtained from both published literature and direct communication with experimenters and include cross sections for nuclear beams on H, He, and heavier targets, and for H and He beams on nuclear targets, for energies >30 MeV/nucleon. These cross sections are directly applicable to calculations involving cosmic ra… more
Date: August 1, 1989
Creator: Crawford, H. J.; Engelage, J.; Jones, F. C.; Guzik, T. G.; Mitchell, J. W.; Wefel, J. P. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Fuel debris assessment for Three Mile Island Unit 2 (TMI-2) reactor recovery by gamma-ray and neutron dosimetry

Description: As a result of the accident on March 28, 1979, fuel debris was dispersed into the primary coolant system of the Three Mile Island Unit 2 (TMI-2) reactor. Location and quantification of fuel debris is essential for TMI-2 recovery. TMI-2 fuel debris assessments can be carried out nondestructively by neutron and gamma-ray dosimetry. Efforts to date have been directed toward fuel debris characterization of the makeup and purification demineralizers, will maintain reactor coolant water purity. Two h… more
Date: August 22, 1983
Creator: Gold, R.; Roberts, J. H.; McNeece, J. P.; Kaiser, B. J.; Ruddy, F. H.; Preston, C. C. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Investigation of parton fragmentation with the TPC detector at PEP: recent results

Description: Long-range correlations are discussed as a new tool to test the parton model and jet universality and are used to determine general properties of quark fragmentation functions. Proton-antiproton correlatiosns and proton rapidity distribution yield information about details of the confinement process, excluding e.g. the decay of heavy mesonic clusters as the dominant source of baryons.
Date: August 1, 1985
Creator: Hofmann, W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Modeling NIF Experimental Designs with Adaptive Mesh Refinement and Lagrangian Hydrodynamics

Description: Incorporation of adaptive mesh refinement (AMR) into Lagrangian hydrodynamics algorithms allows for the creation of a highly powerful simulation tool effective for complex target designs with three-dimensional structure. We are developing an advanced modeling tool that includes AMR and traditional arbitrary Lagrangian-Eulerian (ALE) techniques. Our goal is the accurate prediction of vaporization, disintegration and fragmentation in National Ignition Facility (NIF) experimental target elements. … more
Date: August 31, 2005
Creator: Koniges, A E; Anderson, R W; Wang, P; Gunney, B N; Becker, R; Eder, D C et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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MARS vessel safety analysis. LATA report No. 115

Description: A previous study was performed to assess the hazards associated with an accidental leakage of cooling water into the crucible of molten /sup 238/U for the MARS laser isotope separation experiment. Since that study found that the probability of such an explosion is extremely low during an accidental cooling system failure, a study was conducted to define a more realistic design basis accident (DBA) for the final MARS configuration. If the vapor-phase explosion is considered to be a significant t… more
Date: August 1, 1979
Creator: Rigdon, L.D.; Donham, B.J. & Hughes, P.S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Test of Quark Fragmentation in the Quark-Parton Model Framework

Description: The hadronic system produced in charged-current antineutrino interactions is used to study fragmentation of the d-quark. Some problems encountered in separating the current quark-fragments are discussed. The fragmentation function for the current quark is in good agreement with the expectations of the naive quark-parton model and, in particular, there is no evidence of either a Q/sup 2/- or x/sub BJ/-dependence. 10 references.
Date: August 1, 1979
Creator: Derrick, M.; Barish, S. J. & Barnes, V. E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Production of strange particles in hadronization processes

Description: Strange particles provide an important tool for the study of the color confinement mechanisms involved in hadronization processes. We review data on inclusive strange-particle production and on correlations between strange particles in high-energy reactions, and discuss phenomenological models for parton fragmentation. 58 refs., 24 figs.
Date: August 1, 1987
Creator: Hofmann, W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The study of hadronic matter at the highest density; the search for the deconfined quark-gluon phase using 2 TeV anti p -p collisions; and the exclusive study of nuclear fragmentation using the Lawrence Berkeley Laboratory EOS-TPC

Description: This report discusses the: Fermilab experiment 735, a search for the quark-gluon plasma; an exclusive study of nuclear fragmentation using the EOS-TPC; and a study of the central rapidity region at the relativistic heavy ion collider.
Date: August 15, 1990
Creator: Scharenberg, R.P. & Hirsch, A.S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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[Studies of target fragmentation in intermediate energy, relativistic and ultra-relativistic nuclear collisions]. Nuclear chemistry progress report, August 1, 1990--August 1, 1991

Description: The work described herein is part of a project involving the study of low energy (< 10 MeV/A), intermediate energy (10--100 MeV/A) and relativistic (> 250 MeV/A) heavy ion reactions. In the low energy regime, we published a monograph on the properties of the heaviest elements and used that publication as a basis for making a set of ``best`` semi-empirical predictions of heavy element decay properties. The intermediate energy research effort focussed upon the completion of studies already begun … more
Date: August 1, 1991
Creator: Loveland, W. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Prediction of minimum UO/sub 2/ particle size based on thermal stress initiated fracture model. [LMFBR]

Description: An analytic study was employed to determine the minimum UO/sub 2/ particle size that could survive fragmentation induced by thermal stresses in a UO/sub 2/-Na Fuel Coolant Interaction (FCI). A brittle fracture mechanics approach was the basis of the study whereby stress intensity factors K/sub I/ were compared to the fracture toughness K/sub IC/ to determine if the particle could fracture. Solid and liquid UO/sub 2/ droplets were considered each with two possible interface contact conditions; p… more
Date: August 1, 1976
Creator: Corradini, M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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UFD Storage and Transportation - Transportation Working Group Report

Description: The Used Fuel Disposition (UFD) Transportation Task commenced in October 2010. As its first task, Pacific Northwest National Laboratory (PNNL) compiled a list of structures, systems, and components (SSCs) of transportation systems and their possible degradation mechanisms during extended storage. The list of SSCs and the associated degradation mechanisms [known as features, events, and processes (FEPs)] were based on the list of used nuclear fuel (UNF) storage system SSCs and degradation mechan… more
Date: August 1, 2011
Creator: Maheras, Steven J. & Ross, Steven B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Inclusive production of vector mesons in e/sup +/e/sup minus/ annihilation at. sqrt. s = 29 GeV

Description: This thesis describes the measurement of multiplicities and differential cross-sections of the /rho//sup 0/, K*/sup 0/, and /phi/ in e/sup +/e/sup -/ annihilation at ..sqrt..s = 29 GeV, using data collected by the TPC/2..gamma.. Detector Facility at PEP. The number of vector mesons per event is determined to be N(/rho//sup 0/) = 0.77 +- 0.08 +- 0.15, N(K*/sup 0/ + /bar K/*/sup 0/) = 0.58 +- 0.05 +- 0.11, and N(/phi/) = 0.076 +- 0.010 +- 0.012. These multiplicities are used to find that the rati… more
Date: August 1, 1988
Creator: Edberg, T. K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Pyrite thermochemistry, ash agglomeration, and char fragmentation during pulverized coal combustion. Quarterly report, March 15, 1988--June 15, 1988

Description: The primary topics in this program are the size distribution of particulates from pulverized coal firing and the thermochemical transformations of pyrite at typical p. f. firing conditions. In the laboratory, both of these aspects involve representative sampling of particulates from a high temperature combustor, as well as synthetic model fuels with specified pore structure and pyrite loadings. During the period March 15, 1988 through June 15, 1988 we continued to develop the components for rep… more
Date: August 1, 1988
Creator: Akan-Etuk, A.; Niksa, S. & Kruger, C. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Accretion onto the first stellar mass black holes

Description: The first stars, forming at redshifts z &gt; 15 in minihalos with M {approx} 10{sup 5-6} M{sub {circle_dot}} may leave behind remnant black holes, which could conceivably have been the 'seeds' for the supermassive black holes observed at z {approx}&lt; 7. We study remnant black hole growth through accretion, including for the first time the radiation emitted due to accretion, with adaptive mesh refinement cosmological radiation-hydrodynamical simulations. The effects of photo-ionization and hea… more
Date: August 5, 2009
Creator: Alvarez, Marcelo A.; Wise, John H. & Abel, Tom
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Topics in Hadronic Physics

Description: Hadron production cross sections are calculated in the perturbative QCD frame work. Parton distribution functions are obtained from a strip-soliton model. The fragmentation functions are derived from the Lund model of string breaking.
Date: August 1, 2002
Creator: Tang, Alfred
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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Gamow-Teller Strength in the A=14 Multiplet: A Challenge to the Shell Model

Description: A new experimental approach to the famous problem of the anomalously slow Gamow-Teller (GT) transitions in the {beta} decay of the A = 14 multiplet is presented. The GT strength distributions to excited states in {sup 14}C and {sup 14}O was studied in high-resolution (d,{sup 2}He) and ({sup 3}He,t) charge-exchange reactions on {sup 14}N. No-core shell-model (NCSM) calculations capable of reproducing the suppression of the {beta} decays predict a selective excitation of J{sup {pi}} = 2{sup +} st… more
Date: August 7, 2006
Creator: Negret, A.; Adachi, T.; Barrett, B. R.; Baumer, C.; den Berg, A. V.; Berg, G. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Hierarchical Material Models for Fragmentation Modeling in NIF-ALE-AMR

Description: Fragmentation is a fundamental process that naturally spans micro to macroscopic scales. Recent advances in algorithms, computer simulations, and hardware enable us to connect the continuum to microstructural regimes in a real simulation through a heterogeneous multiscale mathematical model. We apply this model to the problem of predicting how targets in the NIF chamber dismantle, so that optics and diagnostics can be protected from damage. The mechanics of the initial material fracture depend … more
Date: August 28, 2007
Creator: Fisher, A.; Masters, N.; Koniges, A.; Anderson, R.; Gunney, B.; Wang, P. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Limiting Accretion onto Massive Stars by Fragmentation-Induced Starvation

Description: Massive stars influence their surroundings through radiation, winds, and supernova explosions far out of proportion to their small numbers. However, the physical processes that initiate and govern the birth of massive stars remain poorly understood. Two widely discussed models are monolithic collapse of molecular cloud cores and competitive accretion. To learn more about massive star formation, we perform simulations of the collapse of rotating, massive, cloud cores including radiative heating … more
Date: August 25, 2010
Creator: Peters, Thomas; /ZAH, Heidelberg; Klessen, Ralf S.; /ZAH, Heidelberg /KIPAC, Menlo Park; Mac Low, Mordecai-Mark; Hist., /Amer. Museum Natural et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Gravitational fragmentation in turbulent primordial gas and the initial mass function of Population III stars

Description: We report results from numerical simulations of star formation in the early universe that focus on the dynamical behavior of metal-free gas under different initial and environmental conditions. In particular we investigate the role of turbulence, which is thought to ubiquitously accompany the collapse of high-redshift halos. We distinguish between two main cases: the birth of Population III.1 stars - those which form in the pristine halos unaffected by prior star formation - and the formation o… more
Date: August 25, 2010
Creator: Clark, Paul C.; /ZAH, Heidelberg; Glover, Simon C.O.; /ZAH, Heidelberg; Klessen, Ralf S.; /ZAH, Heidelberg /KIPAC, Menlo Park et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Chamber wall response to target implosion in inertial fusion reactors : new and critical assessments.

Description: The chamber walls in inertial fusion energy (IFE) reactors are exposed to harsh conditions following each target implosion. Key issues of the cyclic IFE operation include intense photon and ion deposition, wall thermal and hydrodynamic evolution, wall erosion and fatigue lifetime, and chamber clearing and evacuation to ensure desirable conditions prior to target implosion. Several methods for wall protection have been proposed in the past, each having its own advantages and disadvantages. These… more
Date: August 5, 2002
Creator: Hassanein, A. & Morozov, V.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Analysis of Fragmentation and Resulting Shrapnel Penetration of Naturally Fragmenting Cylindrical Bombs

Description: Fragmentation of exploding cylinders and penetration mechanics of surrounding vessel walls were examined and a qualitative understanding was achieved. This understanding provided a basis for making simplifying approximations and assumptions that aided in creating a shrapnel penetration model. Several mathematical models were discussed, and results from 6 cylinder tests were analyzed in order to select a model that best represented the data. It was determined that the overall best mathematical m… more
Date: August 1, 2000
Creator: Gardner, S. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Review and Comparison of Web- and Disk-Based Tools for Residential Energy Analysis

Description: There exist hundreds of building energy software tools, both web- and disk-based. These tools exhibit considerable range in approach and creativity, with some being highly specialized and others able to consider the building as a whole. However, users are faced with a dizzying array of choices and, often, conflicting results. The fragmentation of development and deployment efforts has hampered tool quality and market penetration. The purpose of this review is to provide information for defining… more
Date: August 25, 2002
Creator: Mills, Evan
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Bambino: A Silicon Position-Sensitive Detector System for TIGRESS

Description: Bambino is a charge-particle detector system with the capability to provide a sufficient energy and position resolution for recoiling nuclei with Z {le} 20 for the Doppler-shift corrections necessary to maintain the {gamma}-ray resolution in TIGRESS. It consists of two annular silicon detectors having an active inner diameter of 22 mm and outer diameter of 70 mm and a thickness of 140 {micro}m. They will be placed 3 cm from the target and provide solid-angle coverage of 1.15{pi} sr. It has 24 s… more
Date: August 10, 2005
Creator: Wu, C.; Becker, J. A. & Cline, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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