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Difficulties with inferring neutron cross sections from charged-particle reactions

Description: We have investigated problems associated with inferring cross sections for neutron reactions on unstable nuclei in the mass-90 region from charged-particle reactions on nearby stable targets. We conclude that effects due to precompound evaporation, isospin, and multiple reaction paths severely limit the circumstances under which charged-particle studies may be directly and easily converted to neutron cross sections of useful accuracy. 4 refs., 2 figs.
Date: May 7, 1985
Creator: Gardner, D. G. & Gardner, M. A.
Partner: UNT Libraries Government Documents Department
open access

Calculational tools for the evaluation of nuclear cross-section and spectra data

Description: A technique based on discrete energy levels rather than energy level densities is presented for nuclear reaction calculations. The validity of the technique is demonstrated via theoretical and experimental agreement for cross sections, isomer-ratios and gamma-ray strength functions. 50 refs., 7 figs. (WRF)
Date: May 7, 1985
Creator: Gardner, M.A.
Partner: UNT Libraries Government Documents Department
open access

Development of backlighting sources for a Compton radiography diagnostic of Inertial Confinement Fusion targets

Description: We present scaled demonstrations of backlighter sources, emitting Bremsstrahlung x-rays with photon energies above 75 keV, that we will use to record x-ray Compton radiographic snapshots of cold dense DT fuel in inertial confinement fusion implosions at the National Ignition Facility (NIF). In experiments performed at the Titan laser facility at Lawrence Livermore National Laboratory, we measured the source size and the Bremsstrahlung spectrum as a function of laser intensity and pulse length, … more
Date: May 7, 2008
Creator: Tommasini, R.; MacPhee, A.; Hey, D.; Ma, T.; Chen, C.; Izumi, N. et al.
Partner: UNT Libraries Government Documents Department
open access

Mixing and CP violation in the D0 and B0(s) systems

Description: Recent developments for mixing and CP violation in the D0 and Bs systems are reviewed, including (i) the recently emerging evidence for D0-D0bar mixing and the interpretations of the measurements; (ii) the theoretical status of the calculations of Delta(Gamma_D) and Delta(m_D); (iii) some implications of the measurement of Bs mixing for new physics.
Date: May 7, 2007
Creator: Ligeti, Zoltan & Ligeti, Zoltan
Partner: UNT Libraries Government Documents Department
open access

Holographic Grand Unification

Description: No Description Available.
Date: May 7, 2006
Creator: Nomura, Yasunori; Poland, David & Tweedie, Brock
Partner: UNT Libraries Government Documents Department
open access

Lightest Isotope of Bh Produced Via the 209Bi(52Cr,n)260BhReaction

Description: The lightest isotope of Bh known was produced in the new {sup 209}Bi({sup 52}Cr,n){sup 260}Bh reaction at the Lawrence Berkeley National Laboratory's 88-Inch Cyclotron. Positive identification was made by observation of eight correlated alpha particle decay chains in the focal plane detector of the Berkeley Gas-Filled Separator. {sup 260}Bh decays with a 35{sub -9}{sup +19} ms half-life by alpha particle emission mainly by a group at 10.16 MeV. The measured cross section of 59{sub -20}{sup +29}… more
Date: May 7, 2007
Creator: Nelson, Sarah L.; Gregorich, Kenneth E.; Dragojevic, Irena; Garcia, Mitch A.; Gates, Jacklyn M.; Sudowe, Ralf et al.
Partner: UNT Libraries Government Documents Department
open access

Molecular Line Emission from Massive Protostellar Disks: Predictions for ALMA and the EVLA

Description: We compute the molecular line emission of massive protostellar disks by solving the equation of radiative transfer through the cores and disks produced by the recent radiation-hydrodynamic simulations of Krumholz, Klein, & McKee. We find that in several representative lines the disks show brightness temperatures of hundreds of Kelvin over velocity channels {approx} 10 km s{sup -1} wide, extending over regions hundreds of AU in size. We process the computed intensities to model the performance o… more
Date: May 7, 2007
Creator: Krumholz, M R; Klein, R I & McKee, C F
Partner: UNT Libraries Government Documents Department
open access

Regulation of in situ to invasive breast carcinoma transition

Description: The transition of ductal carcinoma in situ (DCIS) to invasive carcinoma is a key event in breast tumor progression that is poorly understood. Comparative molecular analysis of tumor epithelial cells from in situ and invasive tumors has failed to identify consistent tumor stage-specific differences. However, the myoepithelial cell layer, present only in DCIS, is a key distinguishing and diagnostic feature. To determine the contribution of non-epithelial cells to tumor progression, we analyzed th… more
Date: May 7, 2008
Creator: Polyak, Kornelia; Hu, Min; Yao, Jun; Carroll, Danielle K.; Weremowicz, Stanislawa; Chen, Haiyan et al.
Partner: UNT Libraries Government Documents Department
open access

Progress and Design Status of the ITER MSE Diagnostic

Description: The Motional Stark Effect (MSE) diagnostic will be essential for the study of advanced scenarios on ITER and its design is currently underway. In order meet the ITER MSE diagnostic design requirements, two approaches for the measurement are under consideration. The first is based on standard polarimeter techniques to measure the polarization of the emitted light, whereas the second measures the Stark splitting from which |B| can be inferred, where |B| is the magnitude of the total magnetic fiel… more
Date: May 7, 2008
Creator: Makowski, M A; Allen, S L; Holcomb, C T; Lerner, S; Morris, K & Wong, N
Partner: UNT Libraries Government Documents Department
open access

TreeQ-VISTA: An Interactive Tree Visualization Tool with Functional Annotation Query Capabilities

Description: Summary: We describe a general multiplatform exploratorytool called TreeQ-Vista, designed for presenting functional annotationsin a phylogenetic context. Traits, such as phenotypic and genomicproperties, are interactively queried from a relational database with auser-friendly interface which provides a set of tools for users with orwithout SQL knowledge. The query results are projected onto aphylogenetic tree and can be displayed in multiple color groups. A richset of browsing, grouping and que… more
Date: May 7, 2007
Creator: Gu, Shengyin; Anderson, Iain; Kunin, Victor; Cipriano, Michael; Minovitsky, Simon; Weber, Gunther et al.
Partner: UNT Libraries Government Documents Department
open access

Verification of Gyrokinetic (delta)f Simulations of Electron Temperature Gradient Turbulence

Description: The GEM gyrokinetic {delta}f simulation code [Chen, 2003] [Chen, 2007] is shown to reproduce electron temperature gradient turbulence at the benchmark operating point established in previous work [Nevins, 2006]. The electron thermal transport is within 10% of the expected value, while the turbulent fluctuation spectrum is shown to have the expected intensity and two-point correlation function.
Date: May 7, 2007
Creator: Nevins, W. M.; Parker, S. E.; Chen, Y.; Candy, J.; Dimits, A.; Dorland, W. et al.
Partner: UNT Libraries Government Documents Department
open access

The Zeta Potential of Surface-Functionalized Metallic Nanorod Particles in Aqueous Solution

Description: Metallic nanoparticles suspended in aqueous solutions, and functionalized with chemical and biological surface coatings, are important elements in basic and applied nanoscience research. Many applications require an understanding of the electrokinetic or colloidal properties of such particles. In this paper we describe the results of experiments to measure the zeta potential of metallic nanorod particles in aqueous saline solutions, including the effects of pH, ionic strength, metallic composit… more
Date: May 7, 2007
Creator: Dougherty, G M; Rose, K A; Tok, J B; Pannu, S S; Chuang, F S; Sha, M Y et al.
Partner: UNT Libraries Government Documents Department
open access

Target Diagnostic Instrument-Based Controls Framework for the National Ignition Facility

Description: NIF target diagnostics are being developed to observe and measure the extreme physics of targets irradiated by the 192-beam laser. The response time of target materials can be on the order of 100ps--the time it takes light to travel 3 cm--temperatures more than 100 times hotter than the surface of the sun, and pressures that exceed 109 atmospheres. Optical and x-ray diagnostics were developed and fielded to observe and record the results of the first 4-beam experiments at NIF. Hard and soft x-r… more
Date: May 7, 2007
Creator: Shelton, R.; O'Brien, D.; Nelson, J. & Kamperschroer, J.
Partner: UNT Libraries Government Documents Department
open access

Improving the bulk data transfer experience

Description: Scientific computations and collaborations increasingly rely on the network to provide high-speed data transfer, dissemination of results, access to instruments, support for computational steering, etc. The Energy Sciences Network is establishing a science data network to provide user driven bandwidth allocation. In a shared network environment, some reservations may not be granted due to the lack of available bandwidth on any single path. In many cases, the available bandwidth across multiple … more
Date: May 7, 2008
Creator: Guok, Chin; Guok, Chin; Lee, Jason R. & Berket, Karlo
Partner: UNT Libraries Government Documents Department
open access

MODEL 9975 SHIPPING PACKAGE FABRICATION PROBLEMS AND SOLUTIONS

Description: The Model 9975 Shipping Package is the latest in a series (9965, 9968, etc.) of radioactive material shipping packages that have been the mainstay for shipping radioactive materials for several years. The double containment vessels are relatively simple designs using pipe and pipe cap in conjunction with the Chalfont closure to provide a leak-tight vessel. The fabrication appears simple in nature, but the history of fabrication tells us there are pitfalls in the different fabrication methods an… more
Date: May 7, 2008
Creator: May, C & Allen Smith, A
Partner: UNT Libraries Government Documents Department
open access

Developments toward a reliable diode-pumped hydrocarbon-free 795-nm rubidium laser

Description: We report a 795-nm diode-pumpable Rb laser using a buffer gas of pure {sup 3}He. {sup 3}He gas enhances mixing of the Rb fine-structure levels. This enables efficient lasing at reduced He pressures and improved thermal management.
Date: May 7, 2008
Creator: Wu, S S; Soules, T F; Page, R H; Mitchell, S C; Kanz, V K & Beach, R J
Partner: UNT Libraries Government Documents Department
open access

Proceedings of the 1986 summer workshop on antiproton beams in the 2-10 GeV/c range

Description: The possibilities for building a facility for the formation spectroscopy of ''charmonium'' and the study of ''exotics'' at the AGS with high intensity antiproton beams of good resolution and enhanced purity are explored. The performance potential of a number of long beams and the AGS booster are evaluated and costs are estimated. Fluxes of several 10/sup 7/ antiprotons per pulse with purities of 5% to 99% are possible with conventional long beams. A similar total antiproton flux would be availa… more
Date: May 7, 1987
Creator: Lazarus, D. (ed.)
Partner: UNT Libraries Government Documents Department
open access

Operational parameters of a 2. 0-MeV RFQ linac

Description: After extensive upgrading, our radio-frequency quadrupole (RFQ) linac is again installed on the accelerator test stand (ATS). The measured parameters of the RFQ, such as the output transverse emittance, transmitted beam, average energy, and energy spread is presented.
Date: May 7, 1984
Creator: Sander, O. R.; Purser, F. O. & Rusthoi, D. P.
Partner: UNT Libraries Government Documents Department
open access

DT-burning upgrade to MFTF-B

Description: To improve MFTF-B, one must raise the ion energy and the electrostatic confining potential. This requires higher beam energy (200 keV in this case) and, to preserve end-plug adiabaticity and hold higher plasma density in the central cell, a higher level of magnetic field. In the MFTF Upgrade we also want to incorporate the new end plug configuration first invented for the MARS reactor. This new magnet design is compared with the present MFTF-B magnet set. The differences include the addition of… more
Date: May 7, 1984
Creator: Thomassen, K. I.; Logan, B. G.; Doggett, J. N. & Coensgen, F. H.
Partner: UNT Libraries Government Documents Department
open access

Experience with Position Sensitive Neutron Detectors at the Intense Pulsed Neutron Source

Description: At the Intense Pulsed Neutron Source (IPNS) pulses of protons accelerated in a synchrotron produce pulses of fast neutrons via the spallation process in an enriched uranium target. After moderation, the resulting pulses of slow neutrons are directed into beams which serve a variety of neutron scattering instruments. Currently there are thirteen neutron scattering instruments in operation or under development at IPNS, and six of these use position-sensitive neutron detectors (PSDs). These PSDs a… more
Date: May 7, 1990
Creator: Crawford, R. K.; Haumann, J. R.; Schultz, A. J.; Felcher, G. P.; Epperson, J. E.; Thiyagarajan, P. et al.
Partner: UNT Libraries Government Documents Department
open access

Electron motion in solenoidal magnetic fields using a first order symplectic integration algorithm

Description: The use of nonsymplectic procedures in particle tracing codes for relativistic electrons leads to errors that can be reduced only at the expense of using very small integration steps. More accurate results are obtained with symplectic transformations for position and momentum. A first-order symplectic integration procedure requires an iterative calculation of the new position coordinates using the old momenta, but the process usually converges in three or four steps. A first-order symplectic al… more
Date: May 7, 1984
Creator: Fraser, J.S.
Partner: UNT Libraries Government Documents Department
open access

Producing thermochemical hydrogen with the tandem-mirror reactor

Description: Fusion power holds the promise to supply not only electricity but also fuels to meet the balance of our energy needs. A new integrated power and breeding blanket design is described for tandem mirror reactors. The blanket incorporates features that make it suitable for synthetic fuel production. In particular, it is matched to the thermal and electrical power requirements of the General Atomic water-splitting process for production of hydrogen. Some improvements to the high temperature chemical… more
Date: May 7, 1982
Creator: Werner, R. W. & Hickman, R. G.
Partner: UNT Libraries Government Documents Department
open access

Solid-State Heat-Capacity-Laser Review

Description: We describe our recent progress in the area of solid-state heat-capacity-lasers (SSHCL). In particular, we examine the physics of heat-capacity operation of a solid state laser and give the present technology status of our 10 kW flashlamp-pumped laser The current status of work leading to a diode-pumped Nd:GGG HCL is also described.
Date: May 7, 2002
Creator: Rotter, M D & Dane, C B
Partner: UNT Libraries Government Documents Department
open access

The ASCI PSE Milepost: Run-Time Systems Performance Tests

Description: The Accelerated Strategic Computing Initiative (ASCI) Problem Solving Environment (PSE) consists of the tools and libraries needed for the development of ASCI simulation codes on ASCI machines. The recently completed ASCI PSE Milepost demonstrated that this software environment is available and functional at the scale used for application mileposts on ASCI White. As part of the PSE Milepost, we performed extensive performance testing of several critical run-time based systems. In this paper, we… more
Date: May 7, 2001
Creator: de Supinski, B R
Partner: UNT Libraries Government Documents Department
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