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in creator/contributor: "Lawrence Berkeley National Laboratory. Nuclear Science Division."

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Hyperon Polarization in Unpolarized Scattering Processes

Transverse polarization in the Hyperon (\Lambda) production in the unpolarizeddeep inelastic scattering and pp collisions is studied in the twist-three approach, considering the contribution from the quark-gluon-antiquark correlation distribution in nucleon. We further compare our results for deep inelastic scattering to a transverse momentum dependent factorization approach, and find consistency between the two approaches in the intermediate transverse momentum region. We also find that in pp … more

Date: August 27, 2008

Creator: Zhou, Jian; Yuan, Feng & Liang, Zuo-Tang

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Cold Fusion Production and Decay of Neutron-Deficient Isotopes of Dubnium and Development of Extraction Systems for Group V Elements

Excitation functions for the 1n and 2n exit channels of the 208Pb(51V,xn)259-xDb reaction were measured. A maximum cross section of the 1n exit channel of 2070+1100/-760 pb was measured at an excitation energy of 16.0 +- 1.8 MeV. For the 2n exit channel, a maximum cross section of 1660+450/-370 pb was measured at 22.0 +- 1.8 MeV excitation energy. The 1n excitation function for the 209Bi(50Ti,n)258Db reaction was remeasured, resulting in a cross section of 5480+1730/1370 pb at an excitation ene… more

Date: July 31, 2008

Creator: Gates, Jacklyn M.

Item Type: Thesis or Dissertation

Partner: UNT Libraries Government Documents Department

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Strangelet Search at the BNL Relativistic Heavy Ion Collider

We have searched for strangelets in a triggered sample of 61 million central (top 4percent) Au+Au collisions at sqrt sNN = 200 GeV near beam rapidities at the STAR solenoidal tracker detector at the BNL Relativistic Heavy Ion Collider. We have sensitivity to metastable strangelets with lifetimes of order>_0.1 ns, in contrast to limits over ten times longer in BNL Alternating Gradient Synchrotron (AGS) studies and longer still at the CERN Super Proton Synchrotron (SPS). Upper limits of a few … more

Date: November 27, 2005

Creator: Ritter, Ha

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Neutron Soft Errors in Xilinx FPGAs at Lawrence Berkeley National Laboratory

The LBNL 88-Inch Cyclotron offers broad-spectrum neutrons for single event effects testing. We discuss results from this beamline for neutron soft upsets in Xilinx Virtex-4 and -5 field-programmable-gate-array (FPGA) devices.

Date: July 25, 2008

Creator: George, Jeffrey S.; Koga, Rocky & McMahan, Margaret A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Multi-year search for a diffuse flxu of muon neutrinos with AMANDA-II

A search for TeV-PeV muon neutrinos from unresolved sources was performed on AMANDA-II data collected between 2000 and 2003 with an equivalent livetime of 807 days. This diffuse analysis sought to find an extraterrestrial neutrino flux from sources with non-thermal components. The signal is expected to have a harder spectrum than the atmospheric muon and neutrino backgrounds. Since no excess of events was seen in the data over the expected background, an upper limit of E{sup 2}{Phi}{sub 90%C.L.… more

Date: April 13, 2008

Creator: Collaboration, IceCube; Klein, Spencer; Achterberg, A. & Collaboration, IceCube

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

The influence of projectile neutron number in the 208Pb(48Ti, n)255Rf and 208Pb(50Ti, n)257Rf reactions

Four isotopes of rutherfordium,254-257Rf, were produced by the 208Pb(48Ti, xn)256-xRf and 208Pb(50Ti, xn)258-xRf reactions (x = 1, 2) at the Lawrence Berkeley National Laboratory 88-Inch Cyclotron. Excitation functions were measured for the 1n and 2n exit channels. A maximum likelihood technique, which correctly accounts for the changing cross section at all energies subtended by the targets, was used to fit the 1n data to allow a more direct comparison between excitation functions obtained und… more

Date: July 11, 2008

Creator: Dragojevic, Irena; Dragojevic, I.; Gregorich, K. E.; Dullmann, Ch. E.; Garcia, M. A.; Gates, J. M. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

QCD Evolution of the Transverse Momentum Dependent Correlations

We study the QCD evolution for the twist-three quark-gluon correlation functions associated with the transverse momentum odd quark distributions. Different from that for the leading twist quark distributions, these evolution equations involve more general twist-three functions beyond the correlation functions themselves. They provide important information on nucleon structure, and can be studied in the semi-inclusive hadron production in deep inelastic scattering and Drell-Yan lepton pair produ… more

Date: December 10, 2008

Creator: Zhou, Jian; Liang, Zuo-Tang & Yuan, Feng

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Phases of QCD: Summary of the Rutgers Long Range Plan Town Meeting, January 12-14, 2007

This White Paper summarizes the outcome of the Town Meeting on Phases of QCD that took place January 12-14, 2007 at Rutgers University, as part of the NSAC 2007 Long Range Planning process. The meeting was held in conjunction with the Town Meeting on Hadron Structure, including a full day of joint plenary sessions of the two meetings. Appendix A.1 contains the meeting agenda. This Executive Summary presents the prioritized recommendations that were determined at the meeting. Subsequent chapters… more

Date: May 14, 2007

Creator: Jacobs, Peter; Kharzeev, Dmitri; Muller, Berndt; Nagle, Jamie; Rajagopal, Krishna & Vigdor, Steve

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Small-Scale Readout Systems Prototype for the STAR PIXEL Detector

A prototype readout system for the STAR PIXEL detector in the Heavy Flavor Tracker (HFT) vertex detector upgrade is presented. The PIXEL detector is a Monolithic Active Pixel Sensor (MAPS) based silicon pixel vertex detector fabricated in a commercial CMOS process that integrates the detector and front-end electronics layers in one silicon die. Two generations ofMAPS prototypes designed specifically for the PIXEL are discussed. We have constructed a prototype telescope system consisting of thre… more

Date: October 1, 2008

Creator: Szelezniak, Michal A.; Besson, Auguste; Colledani, Claude; Dorokhov, Andrei; Dulinski, Wojciech; Greiner, Leo C. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Analyses of Oxyanion Materials by Prompt Gamma Activation Analysis

Prompt gamma activation analysis (PGAA) has been used to analyze metal ion oxyanion materials that have multiple applications, including medicine, materials, catalysts, and electronics. The significance for the need for accurate, highly sensitive analyses for the materials is discussed in the context of quality control of end products containing the parent element in each material. Applications of the analytical data for input to models and theoretical calculations related to the electronic and… more

Date: March 24, 2008

Creator: Firestone, Richard B.; Perry, D. L.; English, G. A.; Firestone, R. B.; Leung, K. N.; Garabedian, G. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Correlations and Fluctuations: Status and Perspectives

We will provide an overview of the physics which can be addressed by studying fluctuations and correlations in heavy ion collisions. Observables, which have been discussed in the literature will be briefly reviewed and put in context with experiment and information from Lattice QCD. Special attention will be given to the QCD critical point and the first order co-existence region.

Date: April 15, 2008

Creator: Koch, Volker & Koch, Volker

Item Type: Article

Partner: UNT Libraries Government Documents Department

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A Heavy Flavor Tracker for STAR

The STAR Collaboration proposes to construct a state-of-the-art microvertex detector,the Heavy Flavor Tracker (HFT), utilizing active pixel sensors and silicon strip technology. The HFT will significantly extend the physics reach of the STAR experiment for precision measurement of the yields and spectra of particles containing heavy quarks. This will be accomplished through topological identification of D mesons by reconstruction of their displaced decay vertices with a precision of approximate… more

Date: February 25, 2008

Creator: Chasman, C.; Beavis, D.; Debbe, R.; Lee, J. H.; Levine, M. J.; Videbaek, F. et al.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Excitation Function for the 74Se(18O,p3n) Reaction

The 74Se(18O,p3n)88gNb excitation function was measured and a maximum cross section of 495+-5 mb was observed at and 18O energy of 74.0 MeV. Experimental cross sections were compared to theoretical calculations using the computer code ALICE-91 and the values were found to be in good agreement. The half life of 88gNb was determined to be around 14.56+-0.11 min.

Date: February 2, 2009

Creator: Gates, Jacklyn; Dragojevic, Irena; Dvorak, Jan; Ellison, Paul; Gregorich, Kenneth; Stavsetra, Liv et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Theoretical Overview on Recent Developments in Transverse Spin Physics

Transverse-spin physics has been very active and rapidly developing in the last few years. In this talk, I will briefly summarize recent theoretical developments, focusing on the associated QCD dynamics in transverse spin physics.

Date: January 14, 2009

Creator: Yuan, Feng

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

IceCube: A Cubic Kilometer Radiation Detector

IceCube is a 1 km{sup 3} neutrino detector now being built at the Amudsen-Scott South Pole Station. It consists of 4800 Digital Optical Modules (DOMs) which detect Cherenkov radiation from the charged particles produced in neutrino interactions. IceCube will observe astrophysical neutrinos with energies above about 100 GeV. IceCube will be able to separate {nu}{sub {mu}}, {nu}{sub t}, and {nu}{sub {tau}} interactions because of their different topologies. IceCube construction is currently 50% c… more

Date: June 1, 2008

Creator: Collaboration, IceCube; Klein, Spencer R & Klein, S.R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Collective phenomena in non-central nuclear collisions

Recent developments in the field of anisotropic flow in nuclear collision are reviewed. The results from the top AGS energy to the top RHIC energy are discussed with emphasis on techniques, interpretation, and uncertainties in the measurements.

Date: October 20, 2008

Creator: Voloshin, Sergei A.; Poskanzer, Arthur M. & Snellings, Raimond

Item Type: Book

Partner: UNT Libraries Government Documents Department

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Evidence against correlations between nuclear decay rates and Earth-Sun distance

We have reexamined our previously published data to search for evidence of correlations between the rates for the alpha, beta-minus, beta-plus, and electron capture decays of 22Na, 44Ti, 108Agm, 121Snm, 133Ba, and 241Am and the Earth?Sun distance. We find no evidence for such correlations and set limits on the possible amplitudes of such correlations substantially smaller than those observed in previous experiments.

Date: December 8, 2008

Creator: Norman, Eric B.; Browne, Edgardo; Shugart, Howard A.; Joshi, Tenzing H. & Firestone, Richard B.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Semi-inclusive DIS: Factorization

In this talk, we will present a QCD factorization theorem for the semi-inclusive deep-inelastic scattering with hadrons in the current fragmentation region detected at low transverse momentum. There has been considerable experimental and theoretical interest in semi-inclusive hadron production in deep inelastic scattering (SIDIS) processes. For example, by studying the polarized and unpolarized SIDIS, one will be able to identify the sea quark distribution and polarization in nucleon, and the e… more

Date: December 10, 2008

Creator: Yuan, Feng

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Neutrino Physics with the IceCube Detector

IceCube is a cubic kilometer neutrino telescope under construction at the South Pole.The primary goal is to discover astrophysical sources of high energy neutrinos.We describe the detector and present results on atmospheric muon neutrinos from2006 data collected with nine detector strings.

Date: June 11, 2008

Creator: Collaboration, IceCube; Kiryluk, Joanna & Kiryluk, Joanna

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Standard Practice for Dosimetry of Proton Beams for use in Radiation Effects Testing of Electronics

Representatives of facilities that routinely deliver protons for radiation effect testing are collaborating to establish a set of standard best practices for proton dosimetry. These best practices will be submitted to the ASTM International for adoption.

Date: July 25, 2008

Creator: McMahan, Margaret A.; Blackmore, Ewart; Cascio, Ethan W.; Castaneda, Carlos; von Przewoski, Barbara & Eisen, Harvey

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Recent Development in Proton Spin Physics

In the naive model of the proton, its 1/2 spin is carried by its quark constituents. However, experiments over the last several decades have shown that the quark spin only contribute a small portion of the proton spin. In this talk, I will present recent developments exploring this proton spin puzzle, and focus on the progress made in the last few years on the longitudinal spin physics, the generalized parton distribution physics, and the transverse spin physics.

Date: December 10, 2008

Creator: Yuan, Feng

Item Type: Article

Partner: UNT Libraries Government Documents Department

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The Search for Muon Neutrinos from Northern HemisphereGamma-Ray Bursts with AMANDA

We present the results of the analysis of neutrino observations by the Antarctic Muon and Neutrino Detector Array (AMANDA) correlated with photon observations of more than 400 gamma-ray bursts (GRBs) in the Northern Hemisphere from 1997 to 2003. During this time period, AMANDA's effective collection area for muon neutrinos was larger than that of any other existing detector. Based on our observations of zero neutrinos during and immediately prior to the GRBs in the dataset, we set the most stri… more

Date: May 8, 2007

Creator: Collaboration, IceCube; Klein, Spencer & Achterberg, A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Single Spin Asymmetry in Inclusive Hadron Production in pp Scattering from Collins Mechanism

We study the Collins mechanism contribution to the single transverse spin asymmetry in inclusive hadron production in pp scattering p{up_arrow}p {yields} {pi}X from the leading jet fragmentation. The azimuthal asymmetric distribution of hadron in the jet leads to a single spin asymmetry for the produced hadron in the Lab frame. The effect is evaluated in a transverse momentum dependent model that takes into account the transverse momentum dependence in the fragmentation process. We find the asy… more

Date: April 14, 2008

Creator: Yuan, Feng & Yuan, Feng

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Small-Scale Readout System Prototype for the STAR PIXEL Detector

Development and prototyping efforts directed towards construction of a new vertex detector for the STAR experiment at the RHIC accelerator at BNL are presented. This new detector will extend the physics range of STAR by allowing for precision measurements of yields and spectra of particles containing heavy quarks. The innermost central part of the new detector is a high resolution pixel-type detector (PIXEL). PIXEL requirements are discussed as well as a conceptual mechanical design, a sensor d… more

Date: October 10, 2008

Creator: Szelezniak, Michal; Anderssen, Eric; Greiner, Leo; Matis, Howard; Ritter, Hans Georg; Stezelberger, Thorsten et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department