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Analysis of NSTX Upgrade OH Magnet and Center Stack

Description: The new ohmic heating (OH) coil and center stack for the National Spherical Torus Experiment (NSTX) upgrade are required to meet cooling and structural requirements for operation at the enhanced 1 Tesla toroidal field and 2 MA plasma current. The OH coil is designed to be cooled in the time between discharges by water flowing in the center of the coil conductor. We performed resistive heating and thermal hydraulic analyses to optimize coolant channel size to keep the coil temperature below 100 … more
Date: November 30, 2010
Creator: A. Zolfaghari, P. Titus, J. Chrzanowski, A. Salehzadeh, F. Dahlgren
Partner: UNT Libraries Government Documents Department
open access

Pulsed Gamma-Rays From PSR J2021 3651 with the Fermi Large Area Telescope

Description: We report the detection of pulsed gamma-rays from the young, spin-powered radio pulsar PSR J2021+3651 using data acquired with the Large Area Telescope (LAT) on the Fermi Gamma-ray Space Telescope (formerly GLAST). The light curve consists of two narrow peaks of similar amplitude separated by 0.468 {+-} 0.002 in phase. The first peak lags the maximum of the 2 GHz radio pulse by 0.162 {+-} 0.004 {+-} 0.01 in phase. The integral gamma-ray photon flux above 100 MeV is (56 {+-} 3 {+-} 11) x 10{sup … more
Date: November 30, 2011
Creator: Abdo, Aous A.; Ackermann, M.; Ajello, Marco; Atwood, William B.; Baldini, L.; Ballet, J. et al.
Partner: UNT Libraries Government Documents Department
open access

Local Probe into the Atomic Structure of Metallic Glasses using EELS

Description: Electron energy loss spectroscopy (EELS) is used to extract information on the topological arrangement of atoms around Pd in the bulk-glass-forming Pd{sub 60}Ni{sub 20}P{sub 20}. It is found that the environment around Pd in the glass is only a slight modification of the Pd crystalline structure. However, the modification is enough to allow this alloy to form a glass in bulk. In examining the differences between the structure of crystalline Pd and glassy Pd{sub 60}Ni{sub 20}P{sub 20} it is conc… more
Date: November 30, 1999
Creator: Alamgir, F. M.; Ito, Y.; Schwarz, R. B.; Jain, H. & Williams, D. B.
Partner: UNT Libraries Government Documents Department
open access

A Plasma Lens for Magnetron Sputtering

Description: A plasma lens, consisting of a solenoid and potential-defining ring electrodes, has been placed between a magnetron and substrates to be coated. Photography reveals qualitative information on excitation, ionization, and the transport of plasma to the substrate.
Date: November 30, 2010
Creator: Anders, Andre & Brown, Jeff
Partner: UNT Libraries Government Documents Department
open access

Hollow Plasma in a Solenoid

Description: A ring cathode for a pulsed, high-current, multi-spot cathodic arc discharge was placed inside a pulsed magnetic solenoid. Photography is used to evaluate the plasma distribution. The plasma appears hollow for cathode positions close the center of the solenoid, and it is guided closer to the axis when the cathode is away from the center.
Date: November 30, 2010
Creator: Anders, Andre; Kauffeldt, Marina; Oks, Efim M. & Roy, Prabir K.
Partner: UNT Libraries Government Documents Department
open access

LIFE: The Case for Early Commercialization of Fusion Energy

Description: This paper presents the case for early commercialization of laser inertial fusion energy (LIFE). Results taken from systems modeling of the US electrical generating enterprise quantify the benefits of fusion energy in terms of carbon emission, nuclear waste and plutonium production avoidance. Sensitivity of benefits-gained to timing of market-entry is presented. These results show the importance of achieving market entry in the 2030 time frame. Economic modeling results show that fusion energy … more
Date: November 30, 2010
Creator: Anklam, Thomas; Simon, Aaron J.; Powers, Sarah & Meier, Wayne R.
Partner: UNT Libraries Government Documents Department
open access

Search for Charmonium States Decaying to J/\psi\gamma \gamma $ Using Initial-State Radiation Events

Description: We study the processes e{sup +}e{sup -} {yields} (J/{psi}{gamma}{gamma}){gamma} and e{sup +}e{sup -} {yields} (J/{psi}{pi}{sup -}{pi}{sup +}){gamma} where the hard photon radiated from an initial e{sup +}e{sup -} collision with center-of-mass (CM) energy near 10.58 GeV is detected. In the final state J/{psi}{gamma}{gamma} we consider J/{psi}{pi}{sup 0}, J/{psi}{eta}, {chi}{sub c1}{gamma}, and {chi}c{sub 2}{gamma} candidates. The invariant mass of the hadronic final state defines the effective e… more
Date: November 30, 2006
Creator: Aubert, B.; Barate, R.; Bona, M.; Boutigny, D.; Couderc, F.; Karyotakis, Y. et al.
Partner: UNT Libraries Government Documents Department
open access

Measurement of the Absolute Branching FractionsB to D\pi, D^*\pi, D^{**}\pi with aMissing Mass Method

Description: We present branching fraction measurements of charged and neutral B decays to D{pi}{sup -}, D*{pi}{sup -} and D**{pi}{sup -} with a missing mass method, based on a sample of 231 million {Upsilon}(4S) {yields} B{bar B} pairs collected by the BABAR detector at the PEP-II e{sup +}e{sup -} collider. One of the B mesons is fully reconstructed and the other one decays to a reconstructed charged {pi} and a companion charmed meson identified by its recoil mass, inferred by kinematics. Here D** refers t… more
Date: November 30, 2006
Creator: Aubert, B.; Bona, M.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.
Partner: UNT Libraries Government Documents Department
open access

Observation of B^+ to Phi Phi K^+ and Evidence for B^0 to Phi Phi K^0 below Eta_C Threshold.

Description: The authors report measurements of the decays B{sup +} {yields} {phi}{phi}K{sup +} and B{sup 0} {yields} {phi}{phi}K{sup 0} using a sample of 231 million B{bar B} pairs collected with the BABAR detector at the PEP-II asymmetric-energy B Factory at the Stanford Linear Accelerator Center. The branching fractions are measured to be {Beta}(B{sup +} {yields} {phi}{phi}K{sup +}) = (7.5 {+-} 1.0(stat) {+-} 0.7(syst)) x 10{sup -6} and {Beta}(B{sup 0} {yields} {phi}{phi}K{sup 0}) = (4.1{sub -1.4}{sup +1… more
Date: November 30, 2006
Creator: Aubert, B.; Bona, M.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.
Partner: UNT Libraries Government Documents Department
open access

The Taste of Kindness Charity Event

Description: Article about the Taste of Kindness charity event held in Austin, Texas.
Date: November 30, 2017
Creator: Austin Way
Partner: UNT Libraries Special Collections
open access

Performance Modeling: Understanding the Present and Predicting theFuture

Description: We present an overview of current research in performance modeling, focusing on efforts underway in the Performance Evaluation Research Center (PERC). Using some new techniques, we are able to construct performance models that can be used to project the sustained performance of large-scale scientific programs on different systems, over a range of job and system sizes. Such models can be used by vendors in system designs, by computing centers in system acquisitions, and by application scientists… more
Date: November 30, 2005
Creator: Bailey, David H. & Snavely, Allan
Partner: UNT Libraries Government Documents Department
open access

Reliability of Rechargeable Batteries in a Photovoltaic Power Supply System

Description: We investigate the reliability If a rechargeable battery acting as the energy storage component in a photovoltaic power supply system. A model system was constructed for this that includes the solar resource, the photovoltaic power supp Iy system, the rechargeable battery and a load. The solar resource and the system load are modeled as SI ochastic processes. The photovoltaic system and the rechargeable battery are modeled deterministically, imd an artificial neural network is incorporated into… more
Date: November 30, 1998
Creator: Barney, Patrick; Jungst, Rudolph G.; Ingersoll, David; O'Gorman, Christian; Paez, Thomas L. & Urbina, Angel
Partner: UNT Libraries Government Documents Department
open access

Editorial: Biofuels and Bioenergy

Description: Editorial on the research topic of biofuels and bioenergy.
Date: November 30, 2020
Creator: Barros-Rios, Jaime; Zhang, Jin & Lu, Mengzhu
Partner: UNT College of Science
open access

Development and Fabrication of Nb3Sn Rutherford Cable for the 11 T DS Dipole Demonstration Model

Description: Fermilab and CERN started the development of 11 T 11-m long Nb{sub 3}Sn dipoles to replace few regular LHC NbTi dipoles and free space for cold collimators in LHC DS areas. An important step in the design of these magnets is the development of the high aspect ratio Nb{sub 3}Sn cable to achieve the nominal field of 11 T at the nominal LHC operating current of 11.85 kA with 20% margin. The keystoned cables 14.7 mm wide with and without a stainless steel core were made out of hard Cu wires and Nb{… more
Date: November 30, 2011
Creator: Barzi, E.; Lombardo, V.; Nobrega, F.; Turrioni, D.; Yamada, R.; Zlobin, A.V. et al.
Partner: UNT Libraries Government Documents Department
open access

Intrinsic and extrinsic magnetic properties of the naturally layered manganites

Description: Structural and magnetic properties of the two-layered Ruddlesden-Popper phase SrO(La{sub 1{minus}x}Sr{sub x}MnO{sub 3}){sub 2} with x = 0.3--0.5 are highlighted. Intrinsic properties of these naturally layered manganites include a colossal magnetoresistance, a composition-dependent magnetic anisotropy, and almost no remanence. Above the Curie temperature there is a non-vanishing extrinsic magnetization attributed to intergrowths (stacking faults in the layered structure). These lattice imperfec… more
Date: November 30, 1999
Creator: Berger, A.; Mitchell, J. F.; Miller, D. J.; Jiang, J. S. & Bader, S. D.
Partner: UNT Libraries Government Documents Department
open access

Using Laboratory Measurements of Electrical and Mechanical Properties to Assist Interpretation of Field Data from Shallow Geophysical Measurements

Description: Reconstruction of shallow subsurface structure from geophysical data is a central problem for many environmental and engineering applications. We observe that for shallow soil distributions, seismic data alone or electrical data alone may provide a good reconstruction of the subsurface. We show that using joint seismic and electrical data will improve the reconstruction of shallow structure. Our results emphasize that the availability of techniques for making laboratory measurements of ultrason… more
Date: November 30, 2001
Creator: Bertete-Aguirre, H.; Berge, P. A. & Roberts, J. J.
Partner: UNT Libraries Government Documents Department
open access

Startup experience with the MFTF-B ECRH 100 kV dc power supply

Description: One of the 24 Accel dc Power Supplies (ADCPS) originally intended for the Mirror Fusion Test Facility (MFTF-B) Neutral Beam Power Supply (NBPS) System has been converted to provide negative polarity output at 90 kV with a load current of 64 A dc. The load duty cycle is a pulse of 30-seconds duration with a pulse repetition period of five minutes. A new control system has been built which will serve as a prototype for the MFTF-B ADCPS controls, and a test setup was built which will be used to te… more
Date: November 30, 1983
Creator: Bishop, S. R.; Goodman, R. A. & Wilson, J. H.
Partner: UNT Libraries Government Documents Department
open access

Sample environments at the Intense Pulsed Neutron Source (IPNS).

Description: Neutron diffraction is a powerful tool for structural studies of samples in special sample environments because of the high penetrating power of neutrons compared to x-rays. The Intense Pulsed Neutron Source (IPNS) at Argonne National Laboratory (ANL) offers its users a variety of sample environments for pulsed neutron scattering and diffraction experiments. At the present time over 80% of all experiments performed at the IPNS invoke some type of ancillary equipment to control the sample enviro… more
Date: November 30, 1998
Creator: Bohringer, D. E.
Partner: UNT Libraries Government Documents Department
open access

The r-Process in Metal Poor Stars and Black Hole Formation

Description: Nucleosynthesis of heavy nuclei in metal-poor stars is generally ascribed to the r-process, as the abundance pattern in many such stars agrees with the inferred Solar r-process abundances. Nonetheless, a significant number of these stars do not share this r-process template. they suggest that many such stars have begun an r-process, but it was prevented from running to completion in more massive stars by collapse to black holes, creating a 'truncated r-process,' or 'tr-process'. The observed fr… more
Date: November 30, 2011
Creator: Boyd, R. N.; Famiano, M. A.; Meyer, B. S.; Motizuki, Y.; Kajino, T. & Roederer, I. U.
Partner: UNT Libraries Government Documents Department
open access

Hadron Optics in Three-Dimensional Invariant Coordinate Space from Deeply VirtualCompton Scattering

Description: The Fourier transform of the deeply virtual Compton scattering amplitude (DVCS) with respect to the skewness parameter {zeta} = Q{sup 2}/2p {center_dot} q can be used to provide an image of the target hadron in the boost-invariant variable {sigma}, the coordinate conjugate to light-front time {tau} = t + z/c. As an illustration, we construct a consistent covariant model of the DVCS amplitude and its associated generalized parton distributions using the quantum fluctuations of a fermion state at… more
Date: November 30, 2006
Creator: Brodsky, S.J.; Chakrabarti, D.; Harindranath, A.; Mukherjee, A. & Vary, J.P.
Partner: UNT Libraries Government Documents Department
open access

Modifier coordination and phosphate glass networks

Description: The addition of up to approximately 16 mole% Cs{sub 2}O to vitreous P{sub 2}O{sub 5} reduces the glass transition temperature (T{sub g}) by 150 K, whereas further additions up to 50 mole% produce little additional change in T{sub g}. {sup 31}P magic angle spinning nuclear magnetic resonance spectra indicate that the phosphate network is progressively dipolymerized over the entire range of compositions. The property trend is explained by a transition in the Cs{sup +} coordination environment, fr… more
Date: November 30, 1999
Creator: Brow, R.; Click, C. A. & Alam, T. M.
Partner: UNT Libraries Government Documents Department
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