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X-ray backlighting sources of 4 to 10 keV for laser-fusion targets

Description: High-intensity, short-duration x-ray pulses are necessary to diagnose the compression of laser film targets. Present target designs are such that backlighting sources ranging from a few thousand electron volts to 100 keV will be necessary. The desired source durations range from a few tens of picoseconds for flash radiography to several nanoseconds for streaked backlighting, and the source occurrence must be tightly synchronized to that of the target-irradiating laser pulse. For the latter reas… more
Date: May 12, 1981
Creator: Rupert, V. C.; Matthews, D. L. & Koppel, L. N.
Partner: UNT Libraries Government Documents Department
open access

TOUGH+/GasH20 study of the effects of a heat source buried in theMartian permafrost

Description: We use TOUGH+/GasH2O to study the effects of a heat sourceburied in the Martian permafrost to evaluate the possibility ofestablishing a wet zone of liquid water, in which terrestrialmicroorganisms could survive and multiply. Analysis of the problemindicates that (1) only a limited permafrost volume (not exceeding 0.35 min radius) is affected, (2) a "wet" zone with limited amounts of liquidwater de-velops (not exceeding 8 and 0.7 kg for a 250 W and a 62.5 Wsource, respectively), (3) the wet zone… more
Date: May 12, 2006
Creator: Moridis, George J. & Pruess, Karsten
Partner: UNT Libraries Government Documents Department
open access

New developments for the site-specific attachment of protein to surfaces

Description: Protein immobilization on surfaces is of great importance in numerous applications in biology and biophysics. The key for the success of all these applications relies on the immobilization technique employed to attach the protein to the corresponding surface. Protein immobilization can be based on covalent or noncovalent interaction of the molecule with the surface. Noncovalent interactions include hydrophobic interactions, hydrogen bonding, van der Waals forces, electrostatic forces, or physic… more
Date: May 12, 2005
Creator: Camarero, J A
Partner: UNT Libraries Government Documents Department
open access

Verification of high-order mixed FEM solution of transient Magnetic diffusion problems

Description: We develop and present high order mixed finite element discretizations of the time dependent electromagnetic diffusion equations for solving eddy current problems on 3D unstructured grids. The discretizations are based on high order H(grad), H(curl) and H(div) conforming finite element spaces combined with an implicit and unconditionally stable generalized Crank-Nicholson time differencing method. We develop three separate electromagnetic diffusion formulations, namely the E (electric field), H… more
Date: May 12, 2005
Creator: Rieben, R. & White, D. A.
Partner: UNT Libraries Government Documents Department
open access

Vacuum-ultraviolet (VUV) photoionization of small methanol and methanol-water clusters

Description: In this work we report on thevacuum-ultraviolet (VUV) photoionization of small methanol and methanol-water clusters. Clusters of methanol with water are generated via co-expansion of the gas phase constituents in a continuous supersonic jet expansion of methanol and water seeded in Ar. The resulting clusters are investigated by single photon ionization with tunable vacuumultraviolet synchrotron radiation and mass analyzed using reflectron mass spectrometry. Protonated methanol clusters of the f… more
Date: May 12, 2008
Creator: Ahmed, Musahid; Ahmed, Musahid; Wilson, Kevin R.; Belau, Leonid & Kostko, Oleg
Partner: UNT Libraries Government Documents Department
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Response of California temperature to regional anthropogenic aerosol changes

Description: In this paper, we compare constructed records of concentrations of black carbon (BC)--an indicator of anthropogenic aerosols--with observed surface temperature trends in California. Annual average BC concentrations in major air basins in California significantly decreased after about 1990, coincident with an observed statewide surface temperature increase. Seasonal aerosol concentration trends are consistent with observed seasonal temperature trends. These data suggest that the reduction in ant… more
Date: May 12, 2008
Creator: Kirchstetter, Thomas; Novakov, T.; Kirchstetter, T.W.; Menon, S. & Aguiar, J.
Partner: UNT Libraries Government Documents Department
open access

Beam Measurements and Upgrade at BL 7.2, the Second DiagnosticsBeamline of the Advanced Light Source

Description: Beamline 7.2 of the Advanced Light Source (ALS) at theLawrence Berkeley National Laboratory (LBNL) is a beam diagnostics systemthat uses the synchrotron radiation emitted by a dipole magnet. Itconsists of two branches; in the first one the x-ray portion of theradiation is used in a pinhole camera system for measuring the transverseprofile of the beam. The second branch is equipped with an x-ray beamposition monitor (BPM) and with a multipurpose port where the visible andthe far-infrared part of… more
Date: May 12, 2005
Creator: Scarvie, Tom; Sannibale, Fernando; Biocca, Alan; Kelez, Nicholas; Martin, Michael C.; Nishimura, Toshiro et al.
Partner: UNT Libraries Government Documents Department
open access

Integrating Data Clustering and Visualization for the Analysis of 3D Gene Expression Data

Description: The recent development of methods for extracting precise measurements of spatial gene expression patterns from three-dimensional (3D) image data opens the way for new analyses of the complex gene regulatory networks controlling animal development. We present an integrated visualization and analysis framework that supports user-guided data clustering to aid exploration of these new complex datasets. The interplay of data visualization and clustering-based data classification leads to improved vi… more
Date: May 12, 2008
Creator: Data Analysis and Visualization (IDAV) and the Department of Computer Science, University of California, Davis, One Shields Avenue, Davis CA 95616, USA,; nternational Research Training Group ``Visualization of Large and Unstructured Data Sets,'' University of Kaiserslautern, Germany; Computational Research Division, Lawrence Berkeley National Laboratory, One Cyclotron Road, Berkeley, CA 94720, USA; Genomics Division, Lawrence Berkeley National Laboratory, One Cyclotron Road, Berkeley CA 94720, USA; Life Sciences Division, Lawrence Berkeley National Laboratory, One Cyclotron Road, Berkeley CA 94720, USA,; Computer Science Division,University of California, Berkeley, CA, USA, et al.
Partner: UNT Libraries Government Documents Department
open access

Detection of Atmospheric Muon Neutrinoswith the IceCube 9-String Detector

Description: The IceCube neutrino detector is a cubic kilometer TeV to PeV neutrino detector under construction at the geographic South Pole. The dominant population of neutrinos detected in IceCube is due to meson decay in cosmic-ray air showers. These atmospheric neutrinos are relatively well understood and serve as a calibration and verification tool for the new detector. In 2006, the detector was approximately 10% completed, and we report on data acquired from the detector in this configuration. We obse… more
Date: May 12, 2007
Creator: Collaboration, IceCube; Klein, Spencer & Achterberg, A.
Partner: UNT Libraries Government Documents Department
open access

Regulation and drive system for high rep-rate magnetic-pulse compressors

Description: The essentially unlimited rep-rate capability of non-linear magnetic systems has imposed strict requirements on the drive system which initiates the pulse compression. An order of magnitude increase in the rep-rates achieved by the Advanced Test Accelerator (ATA) gas blown system is not difficult to achieve in the magnetic compressor. The added requirement of having a high degree of regulation at the higher rep-rates places strict requirements on the triggerable switch for charging and de-Quein… more
Date: May 12, 1982
Creator: Birx, D. L.; Cook, E. G.; Hawkins, S.; Meyers, A.; Reginato, L. L.; Schmidt, J. A. et al.
Partner: UNT Libraries Government Documents Department
open access

New possibilities for exotic hadrons

Description: New theoretical ideas and experimental evidence for exotic hadrons are presented. A new exciting candidate is an anticharmed baryon; i.e., a bound state of a nucleon and an F (now called D3). New experimental evidence for four-quark exotic mesons presented at this conference is discussed. The confusion in the E-iota region and the pseudoscalar spectrum still await further experimental clarification.
Date: May 12, 1987
Creator: Lipkin, Harry J.
Partner: UNT Libraries Government Documents Department
open access

Investigation and deactivation of B Plant HEPA filters

Description: This paper describes the integrated approach used to manage environmental, safety, and health considerations related to the B Plant canyon exhaust air filters at the US Department of Energy (DOE) Hanford Site. The narrative illustrates the development and implementation of integrated safety management as applied to a facility and its systems undergoing deactivation. During their lifetime, the high efficiency particulate air (HEPA) filters prevented the release of significant quantities of radio… more
Date: May 12, 1997
Creator: Roege, P. E.
Partner: UNT Libraries Government Documents Department
open access

Simulation of transient effects in the heavy ion fusion injectors

Description: We have used the 2-D PIC code, GYMNOS, to study the transient behaviors in the Heavy Ion Fusion (HIF) injectors. GYMNOS simulations accurately provide the steady state Child-Langmuir current and the beam transient behavior within a planar diode. The simulations of the LBL HIF ESAC injector experiments agree well with the experimental data and EGUN steady state results. Simulations of the nominal HIF injectors have revealed the need to design the accelerating electrodes carefully to control the … more
Date: May 12, 1993
Creator: Chen, Yu-Jiuan & Hewett, D. W.
Partner: UNT Libraries Government Documents Department
open access

Linear Model for Non Isosceles Absorbers.

Description: Previous analyses have assumed that wedge absorbers are triangularly shaped with equal angles for the two faces. In this case, to linear order, the energy loss depends only on the position in the direction of the face tilt, and is independent of the incoming angle. One can instead construct an absorber with entrance and exit faces facing rather general directions. In this case, the energy loss can depend on both the position and the angle of the particle in question. This paper demonstrates tha… more
Date: May 12, 2003
Creator: Berg, J. S.
Partner: UNT Libraries Government Documents Department
open access

DESIGN, CONSTRUCTION, AND STATUS OF ALL NIOBIUM SUPERCONDUCTING PHOTOINJECTOR AT BNL.

Description: We present here the design and construction of an all niobium superconducting RF injector to generate high average current, high brightness electron beam. A 1/2 cell superconducting cavity has been designed, built, and tested. A cryostat has been built to cool the cavity to {approx}2 K. The RF system can deliver up to 500 W at 1.3 GHz to the cavity. A mode-locked Nd:YVO{sub 4} laser, operating at 266 nm with 0.15 W average power, phase locked to the RF, will irradiate a laser cleaned Nb surface… more
Date: May 12, 2004
Creator: SRINIVASAN-RAO,T. BEN-ZVI,I. BURRILL,A. CITVER,G. ET AL.
Partner: UNT Libraries Government Documents Department
open access

ACTION AND PHASE ANALYSIS TO DETERMINE SEXTUPOLE ERRORS IN RHIC AND THE SPS.

Description: Success in the application of the action and phase analysis to find linear errors at RHIC Interaction Regions [1] has encouraged the creation of a technique based on the action and phase analysis to find non linear errors. In this paper we show the first attempt to measure the sextupole components at RHIC interaction regions using the action and phase method. Experiments done by intentionally activating sextupoles in RHIC and in SPS [2] will also be analyzed with this method. First results have… more
Date: May 12, 2003
Creator: Cardona, J.; Peggs, S.; Satogata, T. & Tomas, R.
Partner: UNT Libraries Government Documents Department
open access

ELECTRON CLOUD AND PRESSURE RISE SIMULATIONS FOR RHIC.

Description: Beam induced electron multipacting may be among the main reasons for the vacuum pressure rise when circulating high intensity ion and proton beams in RHIC. Latest simulation results are benchmarked with recent experimental observations for RHIC, and compared to other general computer codes. The influence of the electron multipacting to the vacuum properties is also discussed.
Date: May 12, 2003
Creator: IRISO-ARIZ,U. BLASKIEWICZ,M. DREES,A. FISCHER,W. PEGGS,S. TRBOJEVIC,D.
Partner: UNT Libraries Government Documents Department
open access

ADVANCEMENT OF THE RHIC BEAM ABORT KICKER SYSTEM.

Description: As one of the most critical system for RHIC operation, the beam abort kicker system has to be highly available, reliable, and stable for the entire operating range. Along with the RHIC commission and operation, consistent efforts have been spend to cope with immediate issues as well as inherited design issues. Major design changes have been implemented to achieve the higher operating voltage, longer high voltage hold-off time, fast retriggering and redundant triggering, and improved system prot… more
Date: May 12, 2003
Creator: ZHANG,W. AHRENS,L. MI,J. OERTER,B. SANDBERG,J. WARBURTON,D.
Partner: UNT Libraries Government Documents Department
open access

FFAG LATTICE FOR MUON ACCELERATION WITH DISTRIBUTED RF.

Description: A future muon collider or neutrino factory requires fast acceleration to minimize muon decay. We have previously described an FFAG ring that accelerated muons from 10 to 20 GeV in energy. The ring achieved its large momentum acceptance using a low-emittance lattice with a small dispersion. In this paper, we present an update on that ring. We have used design tools that more accurately represent the ring's behavior at large momentum offsets. We have also improved the dynamic aperture from the ea… more
Date: May 12, 2003
Creator: COURANT,E. D..TRBOJEVIC,D. BERG,S. J. BLASKIEWICZ,M. COURANT,E. D..TRBOJEVIC,D. BERG,S. J. BLASKIEWICZ,M. M. PALMER,R. GARREN,A.
Partner: UNT Libraries Government Documents Department
open access

Commissioning Spin Rotators in RHIC.

Description: During the summer of 2002, eight superconducting helical spin rotators were installed into RHIC in order to control the polarization directions independently at the STAR and PHENIX experiments. Without the rotators, the orientation of polarization at the interaction points would only be vertical. With four rotators around each of the two experiments, we can rotate either or both beams from vertical into the horizontal plane through the interaction region and then back to vertical on the other s… more
Date: May 12, 2003
Creator: MacKay, W. W.; Bai, M.; Courant, E. D.; Fischer, W.; Huang, H.; Luccio, A. et al.
Partner: UNT Libraries Government Documents Department
open access

COMMISSIONING OF RHIC DEUTERON - GOLD COLLISIONS.

Description: Deuteron and gold beams have been accelerated to a collision energy of {radical}s = 200 GeV/u in the Relativistic Heavy Ion Collider (RHIC), providing the first asymmetric-species collisions of this complex. Necessary changes for this mode of operation include new ramping software and asymmetric crossing angle geometries. This paper reviews machine performance, problem encountered and their solutions, and accomplishments during the 16 weeks of ramp-up and operations.
Date: May 12, 2003
Creator: SATOGATA,T. AHRENS,L. BAI,M. BEEBE-WANG,J.
Partner: UNT Libraries Government Documents Department
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