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Search for CP Violating Neutral Higgs Bosons in the MSSM at LEP (open access)

Search for CP Violating Neutral Higgs Bosons in the MSSM at LEP

The LEP collaborations ALEPH, DELPHI, L3 and OPAL have searched for the neutral Higgs bosons which are predicted within the framework of the Minimal Supersymmetric Standard Model (MSSM). The data of the four collaborations are statistically combined and show no significant excess of events which would indicate the production of Higgs bosons. The search results are thus used to set upper bounds on the cross sections of various Higgs-like event topologies and limits on MSSM benchmark models, including CP-conserving and CP-violating scenarios. Here, the limits on the model parameters of the CP-violating benchmark scenario CPX and derivates of this scenario are shown.
Date: March 13, 2006
Creator: Bechtle, Philip
Object Type: Article
System: The UNT Digital Library
COUPLED MULTI-ELECTRODE INVESTIGATION OF CREVICE CORROSION OF 316 STAINLESS STEEL (open access)

COUPLED MULTI-ELECTRODE INVESTIGATION OF CREVICE CORROSION OF 316 STAINLESS STEEL

None
Date: March 13, 2006
Creator: Bocher, F.; Presuel-Moreno, F.; Budiansky, N.D. & Scully, J.R.
Object Type: Article
System: The UNT Digital Library
Homosexuals and U.S. Military Policy: Current Issues (open access)

Homosexuals and U.S. Military Policy: Current Issues

This report discusses policy towards homosexuals in the U.S. military service. In 1993, new laws and regulations pertaining to homosexuals and U.S. military service came into effect reflecting a compromise in policy. This compromise, colloquially referred to as “don’t ask, don’t tell,” holds that the presence in the armed forces of persons who demonstrate a propensity or intent to engage in homosexual acts would create an unacceptable risk to the high standards of morale, good order and discipline, and unit cohesion which are the essence of military capability. Service members are not to be asked about nor allowed to discuss their homosexuality. This compromise notwithstanding, the issue has remained politically contentious.
Date: March 13, 2006
Creator: Burrelli, David F. & Dale, Charles V.
Object Type: Report
System: The UNT Digital Library
The Express-Star (Chickasha, Okla.), Ed. 1 Monday, March 13, 2006 (open access)

The Express-Star (Chickasha, Okla.), Ed. 1 Monday, March 13, 2006

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: March 13, 2006
Creator: Bush, Kent
Object Type: Newspaper
System: The Gateway to Oklahoma History
Altus Times (Altus, Okla.), Vol. 107, No. 290, Ed. 1 Monday, March 13, 2006 (open access)

Altus Times (Altus, Okla.), Vol. 107, No. 290, Ed. 1 Monday, March 13, 2006

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: March 13, 2006
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
Measurements of Intra-Beam Scattering at Low Emittance in the Advanced Light Source (open access)

Measurements of Intra-Beam Scattering at Low Emittance in the Advanced Light Source

The beam emittance at the interaction point of linear colliders is expected to be strongly influenced by the emittance of the beams extracted from the damping rings. Intra-beam scattering (IBS) potentially limits the minimum emittance of low-energy storage rings, and this effect strongly influences the choice of energy of damping rings [1]. Theoretical analysis suggests that the NLC damping rings will experience modest emittance growth at 1.98 GeV, however there is little experimental data of IBS effects for very low-emittance machines in the energy regime of interest. The Advanced Light Source (ALS) at Lawrence Berkeley National Laboratory is a third-generation synchrotron light source operating with high-intensity, low-emittance beams at energies of approximately 1-2 GeV, and with emittance coupling capability of 1% or less. We present measurements of the beam growth in three dimensions as a function of current, for normalized natural horizontal emittance of approximately 1-10 mm-mrad at energies of 0.7-1.5 GeV, values comparable to the parameters in an NLC damping ring. Using a dedicated diagnostic beamline with an x-ray scintillator imaging system, measurements of the transverse beamsize are made, and bunch length measurements are made using an optical streak camera. Emittance growth as a function of bunch current is …
Date: March 13, 2006
Creator: Byrd, J.; Corlett, J.; Nishimura, H.; Robin, D.; De Santis, S.; Steier, C. et al.
Object Type: Article
System: The UNT Digital Library
Remaining Sites Verification Package for 100-F-38 Stained Soil Site, Waste Site Reclassification Form 2004-093 (open access)

Remaining Sites Verification Package for 100-F-38 Stained Soil Site, Waste Site Reclassification Form 2004-093

The 100-F-38 Stained Soil site was an area of yellow stained soil that was discoverd while excavating a trench for the placement of electrical conduit. The 100-F-38 Stained Soil site meets the remedial action objectives specified in the Remaining Sites ROD. The results of verification sampling show demonstrate that residual contaminant concentrations support future unrestricted land uses that can be represented by a rural-residential scenario. The results also show that residual contaminant concentrations do not preclude any future uses and allow for unrestricted use of shallow zone soils and the contaminant concentrations remaining in the soil are protective of groundwater and the Columbia River.
Date: March 13, 2006
Creator: Carlson, R. A.
Object Type: Report
System: The UNT Digital Library
Water Resources Development Act (WRDA): Army Corps of Engineers Authorization Issues in the 109th Congress (open access)

Water Resources Development Act (WRDA): Army Corps of Engineers Authorization Issues in the 109th Congress

The Corps is a federal agency in the Department of Defense with military and civilian responsibilities. At the direction of Congress, the Corps plans, builds, operates, and maintains a wide range of water resources facilities in U.S. states and territories.
Date: March 13, 2006
Creator: Carter, Nicole T.
Object Type: Report
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 85, No. 94, Ed. 1 Monday, March 13, 2006 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 85, No. 94, Ed. 1 Monday, March 13, 2006

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: March 13, 2006
Creator: Cash, Wanda Garner
Object Type: Newspaper
System: The Portal to Texas History
Femtosecond Diffractive Imaging with a Soft-X-ray Free-Electron Laser (open access)

Femtosecond Diffractive Imaging with a Soft-X-ray Free-Electron Laser

Theory predicts that with an ultrashort and extremely bright coherent X-ray pulse, a single diffraction pattern may be recorded from a large macromolecule, a virus, or a cell before the sample explodes and turns into a plasma. Here we report the first experimental demonstration of this principle using the FLASH soft X-ray free-electron laser. An intense 25 fs, 4 x 10{sup 13} W/cm{sup 2} pulse, containing 10{sup 12} photons at 32 nm wavelength, produced a coherent diffraction pattern from a nano-structured non-periodic object, before destroying it at 60,000 K. A novel X-ray camera assured single photon detection sensitivity by filtering out parasitic scattering and plasma radiation. The reconstructed image, obtained directly from the coherent pattern by phase retrieval through oversampling, shows no measurable damage, and extends to diffraction-limited resolution. A three-dimensional data set may be assembled from such images when copies of a reproducible sample are exposed to the beam one by one.
Date: March 13, 2006
Creator: Chapman, H. N.; Barty, A.; Bogan, M.; Boutet, S.; Frank, M.; Hau-Riege, S. P. et al.
Object Type: Article
System: The UNT Digital Library
The PEP-II Movable Collimators (open access)

The PEP-II Movable Collimators

Three movable collimators have been manufactured for installation in the PEP-II LER and HER beamlines upstream of BaBar to improve backgrounds in BaBar by a factor of 2. Each collimator has a pair of horizontally opposed, water cooled jaws with RF finger seals all around the edge of the jaws, these seals are the only sliding parts inside the vacuum chamber. Each jaw travels independently through a distance of 16.5 mm (LER) or 21mm (HER) and is supported above the collimator from motorized slideways with position feedback. The larger HER collimator has a titanium sublimation pump incorporated into the underside of the collimator, pumping through RF screens in the bottom of the chamber. Water cooled fixed ramps protect the leading and trailing edges of the jaws.
Date: March 13, 2006
Creator: DeBarger, S.; Metcalfe, S.; Ng, C.; Porter, T. G.; Seeman, J.; Sullivan, M. et al.
Object Type: Article
System: The UNT Digital Library
The PEP-II Lower Pressure HER Vacuum Chamber (open access)

The PEP-II Lower Pressure HER Vacuum Chamber

This new vacuum chamber has been installed from 12 to 21 meters upstream of the BaBar detector in the PEP-II High Energy Ring (HER) to reduce lost particle backgrounds. The backgrounds from HER now dominate the backgrounds in the BaBar detector and the present vacuum pressure is 1 x 10{sup -9} Torr. The new chamber will increase the pumping significantly by adding 18 x 2000 l/s titanium sublimation pumps to the existing 5 x 440 l/s ion pumps, and is expected to reduce the pressure by about a factor of five. Features of the chamber include improved water cooling, improved vacuum conductance through copper RF screens featuring over 15,000 small square holes and the ability to sublimate titanium while the beam is still on.
Date: March 13, 2006
Creator: DeBarger, S.; Metcalfe, S.; Seeman, J.; Sullivan, M.; Wienands, U. & Wright, D.
Object Type: Article
System: The UNT Digital Library
The Status of Normal Conducting RF (NCRF) Guns, a Summary of the ERL 2005 Workshop (open access)

The Status of Normal Conducting RF (NCRF) Guns, a Summary of the ERL 2005 Workshop

The 32nd Advanced ICFA Beam Dynamics Workshop on Energy Recovering Linacs (ERL2005) was held at Jefferson Laboratory, March 20 to 23, 2005. A wide range of ERL-related topics were presented and discussed in several working groups with Working Group 1 concentrated upon the physics and technology issues for DC, superconducting RF (SRF) and normal conducting RF (NCRF) guns. This paper summarizes the NCRF gun talks and reviews the status of NCRF gun technology. It begins with the presentations made on the subject of low-frequency, high-duty factor guns most appropriate for ERLs. One such gun at 433MHz was demonstrated at 25%DF in 1992, while the CW and much improved version is currently being constructed at 700MHz for LANL. In addition, the idea of combining the NCRF gun with a SRF linac booster was presented and is described in this paper. There was also a talk on high-field guns typically used for SASE free electron lasers. In particular, the DESY coaxial RF feed design provides rotationally symmetric RF fields and greater flexibility in the placement of the focusing magnetic field. While in the LCLS approach, the symmetric fields are obtained with a dual RF feed and racetrack cell shape. Although these guns …
Date: March 13, 2006
Creator: Dowell, D. H.; Lewellen, J. W.; Nguyen, D. & Rimmer, R.
Object Type: Article
System: The UNT Digital Library
Investigation of the Aerosol Indirect Effect at the Southern Great Plains Using Ground-Based Remote Sensors and Modeling (open access)

Investigation of the Aerosol Indirect Effect at the Southern Great Plains Using Ground-Based Remote Sensors and Modeling

The attached document is the final report in association with closeout
Date: March 13, 2006
Creator: Feingold, Graham
Object Type: Report
System: The UNT Digital Library
Monitoring Volatile Organic Tank Waste Using Cermet Microsensors (open access)

Monitoring Volatile Organic Tank Waste Using Cermet Microsensors

Presently, very few inexpensive technologies exist in the marketplace that can determine the contents of tank waste or monitor the chemistry of tank constituents in near-real time. The research addressed this problem by developing and assessing ceramic-metallic based microsensors for determining the constituents of a liquid organic storage tank by examining the gases in the headspace of the tank. Overall, the WBO and YSZ sensors responded well to the chemicals in this study. Responses to various concentrations were distinguishable visually. This is a clear indication that pattern recognition tools will be effective in resolving the constituents and concentrations. In tests, such as the test with acetophenone, one sensor, the WBO sensor is not extremely effective. However, the other sensor, the YSZ sensor, is effective in resolving the concentrations. This supports the need to use an array of sensors, as one sensor may be reactive to a compound while another may not. In the course of this research, several interesting phenomena surfaced. New sensors, that were fabricated but not used in a contaminant gas, seemed to function more effectively and predictably if a ?conditioning? step was imposed upon them prior to use in square wave voltammetry. A conditioning step consists of …
Date: March 13, 2006
Creator: Gatliff, Edward G.; Skubal, Laura R. & Vogt, Michael C.
Object Type: Report
System: The UNT Digital Library
Capital night for movies and shakers (open access)

Capital night for movies and shakers

Article about the Texas Film Hall of Fame Awards dinner and other celebrations in the Houston, Texas area in March of 2006.
Date: March 13, 2006
Creator: Hodge, Shelby
Object Type: Article
System: The UNT Digital Library
[Society Section: Houston Chronicle] (open access)

[Society Section: Houston Chronicle]

Articles in the Society section of Houston Chronicle containing information about various events in the Houston, Texas area.
Date: March 13, 2006
Creator: Hodge, Shelby
Object Type: Article
System: The UNT Digital Library

Quantitative Analyses of the Severity of Attack on Crevice Corrosion Surfaces

None
Date: March 13, 2006
Creator: Hodges, A. J. & Kelly, R. G.
Object Type: Presentation
System: The UNT Digital Library
WORKSHOP ON DEVELOPMENT OF RADIONUCLIDE GETTERS FOR THE YUCCA MOUNTAIN WASTE REPOSITORY (open access)

WORKSHOP ON DEVELOPMENT OF RADIONUCLIDE GETTERS FOR THE YUCCA MOUNTAIN WASTE REPOSITORY

One of the important that the U.S. Department of Energy (DOE) is currently undertaking is the development of a high-level nuclear waste repository to be located at Yucca Mountain, Nevada. Concern is generated by the Yucca Mountain Project (YMP) is due to potential releases as groundwater contamination, as described in the Total System Performance Assessment (TSPA). The dose to an off-site individual using this groundwater for drinking and irrigation is dominated by four radionuclides: Tc-99, I-127, Np-237, and U-238. Ideally, this dose would be limited to a single radionuclide, U-238; in other words, YMP would resemble a uranium ore body, a common geologic feature in the Western U.S. For this reason and because of uncertainties in the behavior of Tc-99, I-127, and Np-237, it would be helpful to limit the amount of Tc, I, and Np leaving the repository, which would greatly increase the confidence in the long-term performance of YMP. An approach to limiting the migration of Tc, I, and Np that is complementary to the existing YMP repository design plans is to employ sequestering agents or ''getters'' for these radionuclides such that their migration is greatly hindered, thus decreasing the amount of radionuclide leaving the repository. Development of …
Date: March 13, 2006
Creator: Holt, K. C.
Object Type: Report
System: The UNT Digital Library
Controlled VLS Growth of Indium, Gallium and Tin Oxide Nanowiresvia Chemical Vapor Transport (open access)

Controlled VLS Growth of Indium, Gallium and Tin Oxide Nanowiresvia Chemical Vapor Transport

We utilized a vapor-liquid-solid growth technique to synthesize indium oxide, gallium oxide, and tin oxide nanowires using chemical vapor transport with gold nanoparticles as the catalyst. Using identical growth parameters we were able to synthesize single crystal nanowires typically 40-100 nm diameter and more than 10-100 microns long. The products were characterized by means of XRD, SEM and HRTEM. All the wires were grown under the same growth conditions with growth rates inversely proportional to the source metal vapor pressure. Initial experiments show that different transparent oxide nanowires can be grown simultaneously on a single substrate with potential application for multi-component gas sensors.
Date: March 13, 2006
Creator: Johnson, M.C.; Aloni, S.; McCready, D.E. & Bourret-Courchesne, E.D.
Object Type: Article
System: The UNT Digital Library
Tariff Modifications: Miscellaneous Duty Suspension Bills (open access)

Tariff Modifications: Miscellaneous Duty Suspension Bills

This report focuses briefly on the reasons that duty suspensions have merited congressional attention and on the current procedure by which congressional committees evaluate and select commodities for inclusion in more comprehensive legislation.
Date: March 13, 2006
Creator: Jones, Vivian C.
Object Type: Report
System: The UNT Digital Library
Adaptive Optics Imaging Survey of Luminous Infrared Galaxies (open access)

Adaptive Optics Imaging Survey of Luminous Infrared Galaxies

We present high resolution imaging observations of a sample of previously unidentified far-infrared galaxies at z < 0.3. The objects were selected by cross-correlating the IRAS Faint Source Catalog with the VLA FIRST catalog and the HST Guide Star Catalog to allow for adaptive optics observations. We found two new ULIGs (with L{sub FIR} {ge} 10{sup 12} L{sub {circle_dot}}) and 19 new LIGs (with L{sub FIR} {ge} 10{sup 11} L{sub {circle_dot}}). Twenty of the galaxies in the sample were imaged with either the Lick or Keck adaptive optics systems in H or K{prime}. Galaxy morphologies were determined using the two dimensional fitting program GALFIT and the residuals examined to look for interesting structure. The morphologies reveal that at least 30% are involved in tidal interactions, with 20% being clear mergers. An additional 50% show signs of possible interaction. Line ratios were used to determine powering mechanism; of the 17 objects in the sample showing clear emission lines--four are active galactic nuclei and seven are starburst galaxies. The rest exhibit a combination of both phenomena.
Date: March 13, 2006
Creator: Laag, E. A.; Canalizo, G.; van Breugel, W.; Gates, E. L.; de Vries, W. & Stanford, S. A.
Object Type: Article
System: The UNT Digital Library
Comparison of Experimental to Theoretical Strains During Water Hammer (open access)

Comparison of Experimental to Theoretical Strains During Water Hammer

Experimental strains during water hammer were compared to theoretical equations for strain. These equations were derived from the basic equations of motion, which lead to equations for the hoop stress and hoop strain. In this particular case, a sudden pressure increase increase traveling in a pipe was measured, and the hoop strains resulting from this fluid transient were also measured. Measuring the strains at numerous locations along the pipe permitted comparison of the strains as a function of position with respect to the fluid shock wave. This comparison of strains at different positions along the pipe permits analysis the vibratory nature of the strain in the pipe wall. Essentially, the equations of motion provide an approximate technique to find the maximum stress and strain due to water hammer.
Date: March 13, 2006
Creator: Leishear, Robert
Object Type: Article
System: The UNT Digital Library
Application of a Dynamic Stress Theory to Pike Leaks (open access)

Application of a Dynamic Stress Theory to Pike Leaks

This report talks about Application of a Dynamic Stress Theory to Pike Leaks
Date: March 13, 2006
Creator: Leishear, Robert A.
Object Type: Article
System: The UNT Digital Library