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A Test of HTS Power Cable in a Sweeping Magnetic Field

Description: Short sample HTS power cable composed of multiple 344C-2G strands and designed to energize a fast-cycling dipole magnet was exposed to a sweeping magnetic field in the (2-20) T/s ramping rate. The B-field orientation toward the HTS strands wide surface was varied from 0{sup 0} to 10{sup 0}, in steps of 1{sup 0}. The test arrangement allowed measurement of the combined hysteresis and eddy current power losses. For the validity of these measurements, the power losses of a short sample cable compo… more
Date: November 29, 2011
Creator: Piekarz, H.; Hays, S.; Blowers, J. & Shiltsev, V.
Partner: UNT Libraries Government Documents Department
open access

Simulation of Prompt Emission from GRBs with a Photospheric Component and its Detectability By GLAST

Description: The prompt emission from gamma-ray bursts (GRBs) still requires a physical explanation. Studies of time-resolved GRB spectra, observed in the keV-MeV range, show that a hybrid model consisting of two components, a photospheric and a non-thermal component, in many cases fits bright, single-pulsed bursts as well as, and in some instances even better than, the Band function. With an energy coverage from 8 keV up to 300 GeV, GLAST will give us an unprecedented opportunity to further investigate the… more
Date: November 29, 2011
Creator: Battelino, Milan; Ryde, Felix; Observ., /Stockholm; Omodei, Nicola; /INFN, Pisa; Longo, Francesco et al.
Partner: UNT Libraries Government Documents Department
open access

Massive Stars in Colliding Wind Systems: the GLAST Perspective

Description: Colliding winds of massive stars in binary systems are considered as candidate sites of high-energy non-thermal photon emission. They are already among the suggested counterparts for a few individual unidentified EGRET sources, but may constitute a detectable source population for the GLAST observatory. The present work investigates such population study of massive colliding wind systems at high-energy gamma-rays. Based on the recent detailed model (Reimer et al. 2006) for non-thermal photon pr… more
Date: November 29, 2011
Creator: Reimer, Anita; Reimer, Olaf & /Stanford U., HEPL /KIPAC, Menlo Park
Partner: UNT Libraries Government Documents Department
open access

Propagation of rarefaction pulses in particulate materials with strain-softening behavior

Description: We investigate rarefaction waves in nonlinear periodic systems with a 'softening' power-law relationship between force and displacement to understand the dynamic behavior of this class of materials. A closed form expression describing the shape of the strongly nonlinear rarefaction wave is exact for n = 1/2 and agrees well with the shape and width of the pulses resulting from discrete simulations. A chain of particles under impact was shown to propagate a rarefaction pulse as the leading pulse … more
Date: July 29, 2011
Creator: Herbold, E B & Nesterenko, V F
Partner: UNT Libraries Government Documents Department
open access

GLAMM: Genome-Linked Application for Metabolic Maps

Description: The Genome-Linked Application for Metabolic Maps (GLAMM) is a unified web interface for visualizing metabolic networks, reconstructing metabolic networks from annotated genome data, visualizing experimental data in the context of metabolic networks, and investigating the construction of novel, transgenic pathways. This simple, user-friendly interface is tightly integrated with the comparative genomics tools of MicrobesOnline. GLAMM is available for free to the scientific community at glamm.lbl.… more
Date: May 29, 2011
Creator: Bates, John; Chivian, Dylan & Arkin, Adam
Partner: UNT Libraries Government Documents Department
open access

Calibration of the GLAST Burst Monitor Detectors

Description: The GLAST Burst Monitor (GBM) will augment the capabilities of GLAST for the detection of cosmic gamma-ray bursts by extending the energy range (20 MeV to > 300 GeV) of the Large Area Telescope (LAT) towards lower energies by 2 BGO-detectors (150 keV to 30 MeV) and 12 NaI(Tl) detectors (10 keV to 1 MeV). The physical detector response of the GBM instrument for GRBs is determined with the help of Monte Carlo simulations, which are supported and verified by on-ground calibration measurements, … more
Date: November 29, 2011
Creator: von Kienlin, Andreas; Bissaldi, Elisabetta; Lichti, Giselher G.; Steinle, Helmut; Krumrey, Michael; Gerlach, Martin et al.
Partner: UNT Libraries Government Documents Department
open access

A Nanocrystal Sensor for Luminescence Detection of Cellular Forces

Description: Quantum dots have been used as bright fluorescent tags with high photostability to probe numerous biological systems. In this work we present the tetrapod quantum dot as a dynamic, next-generation nanocrystal probe that fluorescently reports cellular forces with spatial and temporal resolution. Its small size and colloidal state suggest that the tetrapod may be further developed as a tool to measure cellular forces in vivo and with macromolecular spatial resolution.
Date: September 29, 2011
Creator: Choi, Charina; Chou, Jonathan; Lutker, Katie; Werb, Zena & Alivisatos, Paul
Partner: UNT Libraries Government Documents Department
open access

FastQuery: A Parallel Indexing System for Scientific Data

Description: Modern scientific datasets present numerous data management and analysis challenges. State-of-the- art index and query technologies such as FastBit can significantly improve accesses to these datasets by augmenting the user data with indexes and other secondary information. However, a challenge is that the indexes assume the relational data model but the scientific data generally follows the array data model. To match the two data models, we design a generic mapping mechanism and implement an e… more
Date: July 29, 2011
Creator: Chou, Jerry; Wu, Kesheng & Prabhat,
Partner: UNT Libraries Government Documents Department
open access

Ferrimagnetism and disorder of epitaxial Mn2-xCoxVAl Heusler compound thin films

Description: The quaternary full Heusler compound Mn{sub 2-x}Co{sub x}VAl with x = 1 is predicted to be a half-metallic antiferromagnet. Thin films of the quaternary compounds with x = 0-2 were prepared by dc and RF magnetron co-sputtering on heated MgO (0 0 1) substrates. The magnetic structure was examined by x-ray magnetic circular dichroism and the chemical disorder was characterized by x-ray diffraction. Ferrimagnetic coupling of V to Mn was observed for Mn{sub 2}VAl (x = 0). For x = 0.5, we also found… more
Date: January 29, 2011
Creator: Meinert, Markus; Schmalhorst, Jan-Michael; Reiss, Gunter & Arenholz, Elke
Partner: UNT Libraries Government Documents Department
open access

Supernova Remnants And GLAST

Description: It has long been speculated that supernova remnants represent a major source of cosmic rays in the Galaxy. Observations over the past decade have ceremoniously unveiled direct evidence of particle acceleration in SNRs to energies approaching the knee of the cosmic ray spectrum. Nonthermal X-ray emission from shell-type SNRs reveals multi-TeV electrons, and the dynamical properties of several SNRs point to efficient acceleration of ions. Observations of TeV gamma-ray emission have confirmed the … more
Date: November 29, 2011
Creator: Slane, Patrick & Astrophys., /Harvard-Smithsonian Ctr.
Partner: UNT Libraries Government Documents Department
open access

Integrated genomic and transcriptomic analysis reveals mycoparasitism as the ancestoral life style of Trichoderma

Description: Mycoparasitism, a lifestyle where one fungus is parasitic on another fungus has special relevance when the prey is a plant pathogen, providing a strategy for biological control of pests for plant protection. Probably, the most studied biocontrol agents are species of the genus Hypocrea/Trichoderma.
Date: April 29, 2011
Creator: Kubicek, Christian P.; Herrera-Estrella, Alfredo; Seidl, Verena; Le Crom, Stéphane; Martinez, Diego A.; Druzhinina, Irina S. et al.
Partner: UNT Libraries Government Documents Department
open access

Runtime Detection of C-Style Errors in UPC Code

Description: Unified Parallel C (UPC) extends the C programming language (ISO C 99) with explicit parallel programming support for the partitioned global address space (PGAS), which provides a global memory space with localized partitions to each thread. Like its ancestor C, UPC is a low-level language that emphasizes code efficiency over safety. The absence of dynamic (and static) safety checks allows programmer oversights and software flaws that can be hard to spot. In this paper, we present an extension … more
Date: September 29, 2011
Creator: Pirkelbauer, P; Liao, C; Panas, T & Quinlan, D
Partner: UNT Libraries Government Documents Department
open access

A Single Pulse Sub-Nanosecond Proton RFQ

Description: A Radio Frequency Quadrupole (RFQ) linac system has been developed to provide a single pulse of 2 MeV protons with a beam pulse width of {approx}300 ps and a charge of 30 pC, either for injection into a pulsed Dielectric Wall Accelerator or for bombardment of a target to produce a fast neutron pulse. The 1.2 m long RFQ structure operates at 425 MHz and bunches and accelerates a single 2.35 ns beam pulse injected into it at 35 keV using a parallel plate deflector placed directly in front of the … more
Date: March 29, 2011
Creator: Hamm, R. W.; Pearce-Percy, H.; Pearson, D.; Rougieri, M.; Weir, J.; Zografos, A. et al.
Partner: UNT Libraries Government Documents Department
open access

Fast Simulation of Electromagnetic Showers in the ATLAS Calorimeter: Frozen Showers

Description: One of the most time consuming process simulating pp interactions in the ATLAS detector at LHC is the simulation of electromagnetic showers in the calorimeter. In order to speed up the event simulation several parametrisation methods are available in ATLAS. In this paper we present a short description of a frozen shower technique, together with some recent benchmarks and comparison with full simulation. An expected high rate of proton-proton collisions in ATLAS detector at LHC requires large sa… more
Date: November 29, 2011
Creator: Barberio, E.; Boudreau, J.; Butler, B.; Cheung, S. L.; Dell'Acqua, A.; Di Simone, A. et al.
Partner: UNT Libraries Government Documents Department
open access

2011 Clusters, Nanocrystals & Nanostructures Gordon Research Conference

Description: Small particles have been at the heart of nanoscience since the birth of the field and now stand ready to make significant contributions to the big challenges of energy, health and sustainability. Atomic clusters show exquisite size-dependent electronic and magnetic properties and offer a new level of control in catalyses, sensors and biochips; functionalised nanocrystals offer remarkable optical properties and diverse applications in electronic devices, solar energy, and therapy. Both areas ar… more
Date: July 29, 2011
Creator: Wang, Lai-Sheng
Partner: UNT Libraries Government Documents Department
open access

FOUR PI CALIBRATION AND MODELING OF A BARE GERMANIUM DETECTOR IN A CYLINDRICAL FIELD SOURCE

Description: In reference 1 the authors described {gamma}-ray holdup assay of a Mossbauer spectroscopy instrument where they utilized two axial symmetric cylindrical shell acquisitions and two disk source acquisitions to determine Am-241 and Np-237 contamination. The measured contents of the two species were determined using a general detector efficiency calibration taken from a 12-inch point source.2 The authors corrected the raw spectra for container absorption as well as for geometry corrections to trans… more
Date: April 29, 2011
Creator: Dewberry, R. & Young, J.
Partner: UNT Libraries Government Documents Department
open access

Simultaneous Radio to (Sub-) Mm-Monitoring of Variability and Spectral Shape Evolution of Potential GLAST Blazars

Description: The Large Area Telescope (LAT) instrument onboard GLAST offers a tremendous opportunity for future blazar studies. In order to fully benefit from its capabilities and to maximize the scientific return from the LAT, it is of great importance to conduct dedicated multi-frequency monitoring campaigns that will result comprehensive observations. Consequently, we initiated an effort to conduct a GLAST-dedicated, quasi-simultaneous, broad-band flux-density (and polarization) monitoring of potential G… more
Date: November 29, 2011
Creator: Fuhrmann, L.; Zensus, J. A.; Krichbaum, T. P.; Angelakis, E. & Readhead, A. C. S.
Partner: UNT Libraries Government Documents Department
open access

Status and Plans for an SRF Accelerator Test Facility at Fermilab

Description: A superconducting RF accelerator test facility is currently under construction at Fermilab. The accelerator will consist of an electron gun, 40 MeV injector, beam acceleration section consisting of 3 TTF-type or ILC-type cryomodules, and multiple downstream beam lines for testing diagnostics and performing beam experiments. With 3 cryomodules installed this facility will initially be capable of generating an 810 MeV electron beam with ILC beam intensity. The facility can accommodate up to 6 cry… more
Date: July 29, 2011
Creator: Church, M.; Leibfritz, J. & Nagaitsev, S.
Partner: UNT Libraries Government Documents Department
open access

Finding (Or Not) New Gamma-Ray Pulsars with GLAST

Description: Young energetic pulsars will likely be the largest class of Galactic sources observed by GLAST, with many hundreds detected. Many will be unknown as radio pulsars, making pulsation detection dependent on radio and/or x-ray observations or on blind periodicity searches of the gamma-rays. Estimates for the number of pulsars GLAST will detect in blind searches have ranged from tens to many hundreds. I argue that the number will be near the low end of this range, partly due to observations being ma… more
Date: November 29, 2011
Creator: Ransom, Scott M. & /NRAO, Charlottesville
Partner: UNT Libraries Government Documents Department
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