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A High Repetition Rate VUV-Soft X-Ray FEL Concept (open access)

A High Repetition Rate VUV-Soft X-Ray FEL Concept

We report on design studies for a seeded FEL light source that is responsive to the scientific needs of the future. The FEL process increases radiation flux by several orders of magnitude above existing incoherent sources, and offers the additional enhancements attainable by optical manipulations of the electron beam: control of the temporal duration and bandwidth of the coherent output, reduced gain length in the FEL, utilization of harmonics to attain shorter wavelengths, and precise synchronization of the x-ray pulse with seed laser systems. We describe an FEL facility concept based on a high repetition rate RF photocathode gun, that would allow simultaneous operation of multiple independent FEL's, each producing high average brightness, tunable over the VUV-soft x-ray range, and each with individual performance characteristics determined by the configuration of the FEL. SASE, enhanced-SASE (ESASE), seeded, harmonic generation, and other configurations making use of optical manipulations of the electron beam may be employed, providing a wide range of photon beam properties to meet varied user demands.
Date: June 24, 2007
Creator: Corlett, J.; Byrd, J.; Fawley, W. M.; Gullans, M.; Li, D.; Lidia, S. M. et al.
Object Type: Article
System: The UNT Digital Library
Energy dependence of jet transport parameter and parton saturationin quark-gluon plasma (open access)

Energy dependence of jet transport parameter and parton saturationin quark-gluon plasma

We study the evolution and saturation of the gluondistribution function in the quark-gluon plasma as probed by apropagating parton and its effect on the computation of jet quenching ortransport parameter $\hat q $. For thermal partons, the saturation scale$Q2_s$ is found to be proportional to the Debye screening mass $\mu_D2$.For hard probes, evolution at small $x=Q2_s/6ET$ leads to jet energydependence of hat q. We study this dependence for both a conformal gaugetheory in weak and strong coupling limit and for (pure gluon) QCD. Theenergy dependence can be used to extract the shear viscosity $\eta$ ofthe medium since $\eta$ can be related to the transport parameter forthermal partons in a transport description. We also derive upper boundson the transport parameter for both energetic and thermal partons. Thelater leads to a lower bound on shear viscosity-to-entropy density ratiowhich is consistent with the conjectured lower bound $\eta/s\geq 1/4\pi$.Implications on the study of jet quenching at RHIC and LHC and the bulkproperties of the dense matter are discussed.
Date: June 24, 2007
Creator: Casalderrey-Solana, Jorge & Wang, Xin-Nian
Object Type: Article
System: The UNT Digital Library
The Next Generation Air Particle Detectors for the United States Navy (open access)

The Next Generation Air Particle Detectors for the United States Navy

Design and testing of the United States Navy’s next generation air particle detector (NGAPD) is presently underway. The NGAPD is intended for use in nuclear applications for the United States Navy and is being designed to detect airborne Co-60 with a reduction in false alarms and improved ease of use. Features being developed include gamma compensation, low maintenance, commercial off-the-shelf electronics, and spectrum simulation for quality assurance and functional testing applications. By supplying a spectrum simulator, the radon stripping algorithm can be running when a simulated anthropogenic source spectrum (e.g., from Co-60 or transuranics) is superimposed on the radon progeny spectrum. This will allow alarm levels to be tested when the air flow is running and the radon stripping algorithm is providing the instrument response output. Modern units evaluate source spectra with the air flow off and the radon spectrum absent thereby not testing the true system performance which comes out of the radon stripping algorithm. Testing results of the preliminary prototype show promise along with computer simulations of source spectra. Primary testing results taken to date include gamma compensation, thermal insults, vibration and spectrum simulation.
Date: June 24, 2007
Creator: Hayes, Robert & Marianno, Craig
Object Type: Article
System: The UNT Digital Library
Progress in Finite Temperature Lattice Qcd. (open access)

Progress in Finite Temperature Lattice Qcd.

I review recent progress in finite temperature lattice calculations, including the determination of the transition temperature, equation of state, screening of static quarks and meson spectral functions.
Date: June 24, 2007
Creator: Petreczky, P.
Object Type: Article
System: The UNT Digital Library
Advanced Safeguards Approaches for New Reprocessing Facilities (open access)

Advanced Safeguards Approaches for New Reprocessing Facilities

U.S. efforts to promote the international expansion of nuclear energy through the Global Nuclear Energy Partnership (GNEP) will result in a dramatic expansion of nuclear fuel cycle facilities in the United States. New demonstration facilities, such as the Advanced Fuel Cycle Facility (AFCF), the Advanced Burner Reactor (ABR), and the Consolidated Fuel Treatment Center (CFTC) will use advanced nuclear and chemical process technologies that must incorporate increased proliferation resistance to enhance nuclear safeguards. The ASA-100 Project, “Advanced Safeguards Approaches for New Nuclear Fuel Cycle Facilities,” commissioned by the NA-243 Office of NNSA, has been tasked with reviewing and developing advanced safeguards approaches for these demonstration facilities. Because one goal of GNEP is developing and sharing proliferation-resistant nuclear technology and services with partner nations, the safeguards approaches considered are consistent with international safeguards as currently implemented by the International Atomic Energy Agency (IAEA). This first report reviews possible safeguards approaches for the new fuel reprocessing processes to be deployed at the AFCF and CFTC facilities. Similar analyses addressing the ABR and transuranic (TRU) fuel fabrication lines at AFCF and CFTC will be presented in subsequent reports.
Date: June 24, 2007
Creator: Durst, Philip C.; Therios, Ike; Bean, Robert; Dougan, A.; Boyer, Brian; Wallace, Richard et al.
Object Type: Report
System: The UNT Digital Library
Advanced Conceptual Models for Unsaturated and Two-Phase Flow in Fractured Rock (open access)

Advanced Conceptual Models for Unsaturated and Two-Phase Flow in Fractured Rock

The Department of Energy Environmental Management Program is faced with two major issues involving two-phase flow in fractured rock; specifically, transport of dissolved contaminants in the Vadose Zone, and the fate of Dense Nonaqueous Phase Liquids (DNAPLs) below the water table. Conceptual models currently used to address these problems do not correctly include the influence of the fractures, thus leading to erroneous predictions. Recent work has shown that it is crucial to understand the topology, or 'structure' of the fluid phases (air/water or water/DNAPL) within the subsurface.
Date: June 24, 2007
Creator: Rajaram, Harihar; Glass, Robert J.; Nicholl, Michael J. & Wood, Thomas R.
Object Type: Report
System: The UNT Digital Library
Updating the NRC Standard Review Plan - Chapter 8 - Electrical Systems (open access)

Updating the NRC Standard Review Plan - Chapter 8 - Electrical Systems

The Standard Review Plan (SRP) (Reference 2), provides guidance to the regulatory staff of the Nuclear Regulatory Commission (NRC) on performing their safety reviews of applications to construct or operate nuclear power plants, and applications to approve standard designs and sites for nuclear power plants. Chapter 8 of the SRP provides guidance related to the review of station electrical distribution systems described by the applicant in its Design Control Document (DCD) or Safety Analysis Report (SAR). As part of the 2006-2007 SAR update, all sections in this Chapter (8.1, 8.2, 8.3.1, 8.3.2, Appendix 8A, and Appendix 8B) were revised to incorporate new analyses, design approaches, and the lessons learned from the review of the AP 1000 design certification and to assure consistency with the draft Regulatory Guide DG-1145, ''Combined License Applications for Nuclear Power Plants (LWR Edition)''.
Date: June 24, 2007
Creator: Sullivan, K.
Object Type: Article
System: The UNT Digital Library
Polk County Enterprise (Livingston, Tex.), Vol. 125, No. 50, Ed. 1 Sunday, June 24, 2007 (open access)

Polk County Enterprise (Livingston, Tex.), Vol. 125, No. 50, Ed. 1 Sunday, June 24, 2007

Semi-weekly newspaper from Livingston, Texas that includes local, state and national news along with advertising.
Date: June 24, 2007
Creator: White, Barbara
Object Type: Newspaper
System: The Portal to Texas History
The Baytown Sun (Baytown, Tex.), Vol. 86, No. 209, Ed. 1 Sunday, June 24, 2007 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 86, No. 209, Ed. 1 Sunday, June 24, 2007

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: June 24, 2007
Creator: Clements, Clifford E.
Object Type: Newspaper
System: The Portal to Texas History
Rad-hard Luminosity Monitoring for the LHC (open access)

Rad-hard Luminosity Monitoring for the LHC

Luminosity measurements at the high luminosity points of the LHC are very challenging due to the extremely high radiation levels in the order of 180 MGy/yr. They have designed an ionization chamber that uses a flowing inorganic gas mixture and a combination of metals and ceramics. With such a choice, an additional challenge is achieving the necessary speed to be able to resolve bunch-by-bunch luminosity data. They present the design, analysis and experimental results of the early demonstration tests of this device.
Date: June 24, 2007
Creator: Beche, J. F.; Byrd, J. M.; Chow, K.; Denes, P.; Ghiorso, W.; Matis, H. S. et al.
Object Type: Article
System: The UNT Digital Library
The Altus Times (Altus, Okla.), Vol. 109, No. 20, Ed. 1 Sunday, June 24, 2007 (open access)

The Altus Times (Altus, Okla.), Vol. 109, No. 20, Ed. 1 Sunday, June 24, 2007

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: June 24, 2007
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History

Doctoral Recital: 2007-06-24 - Hyo Jung Kim, violin

Recital presented at the UNT College of Music Recital Hall in partial fulfillment of the Doctor of Musical Arts (DMA) degree
Date: June 24, 2007
Creator: Kim, Hyo Jung
Object Type: Sound
System: The UNT Digital Library
Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 92, No. 193, Ed. 1 Sunday, June 24, 2007 (open access)

Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 92, No. 193, Ed. 1 Sunday, June 24, 2007

Daily newspaper from Sapulpa, Oklahoma that includes local, state, and national news along with advertising.
Date: June 24, 2007
Creator: Mattox, Jami
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Panola Watchman (Carthage, Tex.), Vol. 135, No. 45, Ed. 1 Sunday, June 24, 2007 (open access)

The Panola Watchman (Carthage, Tex.), Vol. 135, No. 45, Ed. 1 Sunday, June 24, 2007

Semiweekly newspaper from Carthage, Texas that includes local, state, and national news along with advertising.
Date: June 24, 2007
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
The Express-Star (Chickasha, Okla.), Ed. 1 Sunday, June 24, 2007 (open access)

The Express-Star (Chickasha, Okla.), Ed. 1 Sunday, June 24, 2007

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: June 24, 2007
Creator: Bush, Kent
Object Type: Newspaper
System: The Gateway to Oklahoma History