J/(ps) Production via Initial State Radiation in e+e- ----> (m)+(m)-y at an e+e- Center-of-Mass Energy near 10.6 GeV (open access)

J/(ps) Production via Initial State Radiation in e+e- ----> (m)+(m)-y at an e+e- Center-of-Mass Energy near 10.6 GeV

The authors have used a study of the process e{sup +}e{sup -} {yields} {mu}{sup +}{mu}{sup -} {gamma} at a center-of-mass energy near the {Upsilon}(4S) resonance for a {mu}{sup +}{mu}{sup -} invariant mass range near the J/{psi} mass to extract the cross section {sigma}(e{sup +}e{sup -} {yields} J/{psi}{gamma} {yields} {mu}{sup +}{mu}{sup -}{gamma}). The data set, corresponding to an integrated luminosity of 88.4 fb{sup -1}, was collected using the BABAR detector at the PEP-II collider. They measure the product {Lambda}(J/{psi} {yields} e{sup +}e{sup -}) B(J/{psi} {yields} {mu}{sup +}{mu}{sup -}) to be 0.330 {+-} 0.008 {+-} 0.007 keV. Using the world averages for B(J/{psi} {yields} {mu}{sup +}{mu}{sup -}) and B(J/{psi} {yields} e{sup +}e{sup -}), they derive the J/{psi} electronic and total widths: {Lambda}(J/{psi} {yields} e{sup +}e{sup -}) = 5.61 {+-} 0.20 keV and {Lambda} = 94.7 {+-} 4.4 keV.
Date: November 13, 2003
Creator: Wright, D & Collaboration, T B
Object Type: Article
System: The UNT Digital Library
Measurement of the Branching Fraction and Polarization for the Decay B- ---> D*0K*- (open access)

Measurement of the Branching Fraction and Polarization for the Decay B- ---> D*0K*-

None
Date: November 13, 2003
Creator: Aubert, B; Wright, D & Collaboration, T B
Object Type: Article
System: The UNT Digital Library
Implications of Convective Scrape-Off Layer Transport for Fusion Reactors with Solid and Liquid Walls (open access)

Implications of Convective Scrape-Off Layer Transport for Fusion Reactors with Solid and Liquid Walls

Recent experimental observations in tokamaks indicate enhanced convection of plasma blobs toward the main chamber wall. Potential implications of these observations for reactors are examined here. Two dimensional plasma edge calculations are performed with UEDGE, including convective transport consistent with present experiments. This is coupled to a kinetic neutral calculation using the code NUT, to compute the hot neutral flux to the wall. The inclusion of convection increases sputtering of the wall by roughly an order of magnitude. For tungsten walls, erosion (neglecting re-deposition) is estimated to be {approx}0.6 mm per year. Plasma contamination could be serious for high Z walls of W or Sn, and might preclude ignition (based on empirical screening estimates). Low Z liquid materials offer much better prospects for acceptable plasma contamination. Rough estimates of dust generation from such erosion rates imply significant safety issues. Plasma transport via blobs can also significantly modify models of impurity redeposition.
Date: November 13, 2003
Creator: Kotschenreuther, M; Rognlien, T D & Valanju, P
Object Type: Article
System: The UNT Digital Library
Building 773-A, Lab F003 Glovebox Project Radiological Design Summary Report (open access)

Building 773-A, Lab F003 Glovebox Project Radiological Design Summary Report

Engineering Standards present the radiological design criteria and requirements, which must be satisfied for all SRS facility designs. The radiological design criteria and requirements specified in the standard are based on the Code of Federal Regulations, DOE Orders, Site manuals, other applicable standards, and various DOE guides and handbooks. This report contains top-level requirements for the various areas of radiological protection for workers. For the purposes of demonstrating compliance with these requirements, the designer must examine the requirement for the design and either incorporate or provide a technical justification as to why the requirement is not incorporated. This document reports a radiological design review for the STREAK lab glovebox upgrades of inlet ventilation, additional mechanical and electrical services, new glovebox instrumentation and alarms. This report demonstrates that the gloveboxes meet the radiological design requirements of Engineering Standards.
Date: November 13, 2003
Creator: Gaul, W.C.
Object Type: Report
System: The UNT Digital Library
Department of Energy Support for Operations of the WMO/GAW Quality Control/Science Activity Center for the Americas (open access)

Department of Energy Support for Operations of the WMO/GAW Quality Control/Science Activity Center for the Americas

As a formal activity of the World Meteorological Organization's Global Atmosphere Watch, to provide, through agency collaboration, a center of excellence in the United States that would impose quality assurance techniques on data collected by national air and precipitation quality networks operating in the Americas (north, south, and central).
Date: November 13, 2003
Creator: Hicks, B. B.
Object Type: Report
System: The UNT Digital Library
Smoothing of Diamond-Turned Substrates for Extreme Ultraviolet Illuminators (open access)

Smoothing of Diamond-Turned Substrates for Extreme Ultraviolet Illuminators

Condenser optics in extreme ultraviolet lithography (EUVL) systems are subjected to frequent replacement as they are positioned close to the illumination source, where increased heating and contamination occur. In the case of aspherical condenser elements made by optical figuring/finishing, their replacement can be very expensive (several hundred thousand dollars). One approach to this problem would be to manufacture inexpensive illuminator optics that meet all required specifications and could be replaced at no substantial cost. Diamond-turned metal substrates are a factor of 100 less expensive than conventional aspherical substrates but have insufficient finish, leading to unacceptably low EUV reflectance after multilayer coating. In this work it is shown that, by applying a smoothing film prior to multilayer coating, the high spatial frequency roughness of a diamond-turned metal substrate is reduced from 1.76 to 0.27 nm rms while the figure slope error is maintained at acceptable levels. Metrology tests performed at various stages of the fabrication of the element demonstrated that it satisfied all critical figure and finish specifications as illuminator. Initial experimental results on the stability and performance of the optic under a real EUVL plasma source environment show no accelerated degradation when compared to conventional substrates.
Date: November 13, 2003
Creator: Soufli, R; Spiller, E; Schmidt, M A; Robinson, J C; Baker, S L; Ratti, S et al.
Object Type: Article
System: The UNT Digital Library
Design Integration of Liquid Surface Divertors (open access)

Design Integration of Liquid Surface Divertors

The US Enabling Technology Program in fusion is investigating the use of free flowing liquid surfaces facing the plasma. We have been studying the issues in integrating a liquid surface divertor into a configuration based upon an advanced tokamak, specifically the ARIES-RS configuration. The simplest form of such a divertor is to extend the flow of the liquid first wall into the divertor and thereby avoid introducing additional fluid streams. In this case, one can modify the flow above the divertor to enhance thermal mixing. For divertors with flowing liquid metals (or other electrically conductive fluids) MHD (magneto-hydrodynamics) effects are a major concern and can produce forces that redirect flow and suppress turbulence. An evaluation of Flibe (a molten salt) as a working fluid was done to assess a case in which the MHD forces could be largely neglected. Initial studies indicate that, for a tokamak with high power density, an integrated Flibe first wall and divertor does not seem workable. We have continued work with molten salts and replaced Flibe with Flinabe, a mixture of lithium and sodium fluorides, that has some potential because of its lower melting temperature. Sn and Sn-Li have also been considered, and the initial …
Date: November 13, 2003
Creator: Nygren, R E; Cowgill, D F; Ulrickson, M A; Nelson, B E; Fogarty, P J; Rognlien, T D et al.
Object Type: Article
System: The UNT Digital Library
Development of phosphor scintillator-based detectors for soft x-rayand vacuum ultraviolet spectroscopy of magnetically confined fusion plasmas (open access)

Development of phosphor scintillator-based detectors for soft x-rayand vacuum ultraviolet spectroscopy of magnetically confined fusion plasmas

None
Date: November 13, 2003
Creator: Soukhanovskii, V. A.; Regan, S. P.; May, M. J.; Finkenthal, M. & Moos, H. W.
Object Type: Article
System: The UNT Digital Library
Measurement of the Branching Fraction for B(plus or minus) ----> Xc0K(plus or minus) (open access)

Measurement of the Branching Fraction for B(plus or minus) ----> Xc0K(plus or minus)

None
Date: November 13, 2003
Creator: Wright, D & Collaboration, T B
Object Type: Article
System: The UNT Digital Library
Electronic Structure Calculations of Delta-Pu Based Alloys (open access)

Electronic Structure Calculations of Delta-Pu Based Alloys

First-principles methods are employed to study the ground-state properties of {delta}-Pu-based alloys. The calculations show that an alloy component larger than {delta}-Pu has a stabilizing effect. Detailed calculations have been performed for the {delta}-Pu{sub 1-c}Am{sub c} system. Calculated density of Pu-Am alloys agrees well with the experimental data. The paramagnetic {yields} antiferromagnetic transition temperature (T{sub c}) of {delta}-Pu{sub 1-c}Am{sub c} alloys is calculated by a Monte-Carlo technique. By introducing Am into the system, one could lower T{sub c} from 548 K (pure Pu) to 372 K (Pu{sub 70}Am{sub 30}). We also found that, contrary to pure Pu where this transition destabilizes {delta}-phase, Pu{sub 3}Am compound remains stable in the antiferromagnetic phase that correlates with the recent discovery of a Curie-Weiss behavior of {delta}-Pu{sub 1-c}Am{sub c} at c {approx} 24 at. %.
Date: November 13, 2003
Creator: Landa, A; Soderlind, P & Ruban, A
Object Type: Article
System: The UNT Digital Library
Broken symmetries and dilepton production from gluon fusion in aquark gluon plasma (open access)

Broken symmetries and dilepton production from gluon fusion in aquark gluon plasma

None
Date: November 13, 2003
Creator: Majumder, Abhijit; Bourque, Alex & Gale, Charles
Object Type: Article
System: The UNT Digital Library
A Fusion Reactor Design with a Liquid First Wall and Divertor (open access)

A Fusion Reactor Design with a Liquid First Wall and Divertor

Within the magnetic fusion energy program in the US, a program called APEX is investigating the use of free flowing liquid surfaces to form the inner surface of the chamber around the plasma. As part of this work, the APEX Team has investigated several possible design implementations and developed a specific engineering concept for a fusion reactor with liquid walls. Our approach has been to utilize an already established design for a future fusion reactor, the ARIES-RS, for the basic chamber geometry and magnetic configuration and to replace the chamber technology in this design with liquid wall technology for a first wall and divertor and a blanket with adequate tritium breeding. This paper gives an overview of one design with a molten salt (a mixture of lithium, beryllium and sodium fluorides) forming the liquid surfaces and a ferritic steel for the structural material of the blanket. The design point is a reactor with 3840MW of fusion power of which 767MW is in the form of energetic particles (alpha power) and 3073MW is in the form of neutrons. The alpha plus auxiliary power total 909MW of which 430MW is radiated from the core mostly onto the first wall and the balance …
Date: November 13, 2003
Creator: Nygren, R E; Rognlien, T D; Rensink, M E; Smolentsev, S S; Youssef, M E; Sawan, M Z et al.
Object Type: Article
System: The UNT Digital Library
Radionuclide Mobility at the Nevada Test Site (open access)

Radionuclide Mobility at the Nevada Test Site

Underground nuclear tests conducted at the Nevada Test Site (NTS) are characterized by abundant fission product and actinide source terms. Included are {sup 99}Tc and other soluble radionuclides ({sup 3}H, {sup 14}C, {sup 36}Cl, {sup 85}Kr, and {sup 129}I), which are presumably mobile in groundwater and potentially toxic to down-gradient receptors. NTS provides the Office of Civilian Radioactive Waste Management (OCRWM) with an analog of the release of these radionuclides from a nuclear waste repository in the absence of engineered barriers. The investigation described in this report synthesizes a substantial body of data collected on the identity and distribution of soluble radionuclides at field scales over distances of hundreds of meters, for durations up to 40 years, and under hydrogeologic conditions very similar to the proposed geological repository at Yucca Mountain. This body of data is complemented by laboratory transport studies and a synthesis of recent modeling investigations from the NTS, with an emphasis on the ongoing Yucca Mountain Program (YMP) efforts. Overall, understanding the controls of radionuclide mobility associated with these nuclear tests will provide insight into the repository's future performance as well as bounds and calibrations for the numerical predictions of long-term radionuclide releases and migration.
Date: November 13, 2003
Creator: Hu, Qinhong (Max); Smith, David K.; Rose, Timothy; Glascoe, Lee; Steefel, Carl & Zavarin, Mavrik
Object Type: Report
System: The UNT Digital Library