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First year operational experience with the Cherenkov Detector (DIRC) of BaBar (open access)

First year operational experience with the Cherenkov Detector (DIRC) of BaBar

The DIRC (acronym for Detection of Internally Reflected Cherenkov (light)) is a new type of Cherenkov ring imaging detector based on total internal reflection that is used for the first time in the BaBar detector at PEP-II ring of SLAC. The Cherenkov radiators are long rectangular bars made of synthetic fused silica. The photon detector is a water tank equipped with an array of 10,752 conventional photomultipliers. The first year operational experience in the BaBar detector is presented using cosmic data and collision data in the energy region of the Y(4s) resonance.
Date: April 1, 2000
Creator: Adam, I. & Collaboration, BaBar
Object Type: Article
System: The UNT Digital Library
Production of e+e- Pairs Accompanied by Nuclear Dissociation in Ultra-peripheral Heavy Ion Collisions (open access)

Production of e+e- Pairs Accompanied by Nuclear Dissociation in Ultra-peripheral Heavy Ion Collisions

We present the first data on e{sup +}e{sup -} pair production accompanied by nuclear breakup in ultra-peripheral gold-gold collisions at a center of mass energy of 200 GeV per nucleon pair. The nuclear breakup requirement selects events at small impact parameters, where higher-order corrections to the pair production cross section should be enhanced. We compare the pair kinematic distributions with two calculations: one based on the equivalent photon approximation, and the other using lowest-order quantum electrodynamics (QED); the latter includes the photon virtuality. The cross section, pair mass, rapidity and angular distributions are in good agreement with both calculations. The pair transverse momentum, p{sub T}, spectrum agrees with the QED calculation, but not with the equivalent photon approach. We set limits on higher-order contributions to the cross section. The e{sup +} and e{sup -} p{sub T} spectra are similar, with no evidence for interference effects due to higher-order diagrams.
Date: April 7, 2004
Creator: Adams, J.; Adler, C.; Aggarwal, M. M.; Ahammed, Z.; Allgower, C.; Amonett, J. et al.
Object Type: Article
System: The UNT Digital Library
Centrality and pseudorapidity dependence of charged hadron production at intermediate p{sub T} in Au+Au collisions at {radical}s{sub NN} = 130 GeV (open access)

Centrality and pseudorapidity dependence of charged hadron production at intermediate p{sub T} in Au+Au collisions at {radical}s{sub NN} = 130 GeV

We present STAR measurements of charged hadron production as a function of centrality in Au + Au collisions at {radical}s{sub NN} = 130 GeV. The measurements cover a phase space region of 0.2 < p{sub T} < 6.0 GeV/c in transverse momentum and -1 < {eta} < 1 in pseudorapidity. Inclusive transverse momentum distributions of charged hadrons in the pseudorapidity region 0.5 < |{eta}| < 1 are reported and compared to our previously published results for |{eta}| < 0.5. No significant difference is seen for inclusive p{sub T} distributions of charged hadrons in these two pseudorapidity bins. We measured dN/d{eta} distributions and truncated mean p{sub T} in a region of p{sub T} > p{sub T}{sup cut}, and studied the results in the framework of participant and binary scaling. No clear evidence is observed for participant scaling of charged hadron yield in the measured p{sub T} region. The relative importance of hard scattering process is investigated through binary scaling fraction of particle production.
Date: April 15, 2004
Creator: Adams, J.; Aggarwal, M. M.; Ahammed, Z.; Amonett, J.; Anderson, B. D.; Arkhipkin, D. et al.
Object Type: Article
System: The UNT Digital Library
Incident Energy Dependence of pt Correlations at RHIC (open access)

Incident Energy Dependence of pt Correlations at RHIC

We present results for two-particle transverse momentum correlations, ({Delta}p{sub t,i}{Delta}p{sub t,j}), as a function of event centrality for Au+Au collisions at {radical}s{sub NN} = 20, 62, 130, and 200 GeV at the Relativistic Heavy Ion Collider. We observe correlations decreasing with centrality that are similar at all four incident energies. The correlations multiplied by the multiplicity density increase with incident energy and the centrality dependence may show evidence of processes such as thermalization, jet production, or the saturation of transverse flow. The square root of the correlations divided by the event-wise average transverse momentum per event shows little or no beam energy dependence and generally agrees with previous measurements at the Super Proton Synchrotron.
Date: April 29, 2005
Creator: Adams, J.; Aggarwal, M. M.; Ahammed, Z.; Amonett, J.; Anderson, B. D.; Arkhipkin, D. et al.
Object Type: Article
System: The UNT Digital Library
Centrality and pseudorapidity dependence of charged hadron production at intermediate p{sub t} in Au+Au collisions at {radical}s{sub NN} = 130 GeV (open access)

Centrality and pseudorapidity dependence of charged hadron production at intermediate p{sub t} in Au+Au collisions at {radical}s{sub NN} = 130 GeV

We present STAR measurements of charged hadron production as a function of centrality in Au + Au collisions at {radical}s{sub NN} = 130 GeV. The measurements cover a phase space region of 0.2 < p{sub T} < 6.0 GeV/c in transverse momentum and 11 < {eta} < 1 in pseudorapidity. Inclusive transverse momentum distributions of charged hadrons in the pseudorapidity region 0.5 < |{eta}| < 1 are reported and compared to our previously published results for |{eta}| < 0.5. No significant difference is seen for inclusive p{sub T} distributions of charged hadrons in these two pseudorapidity bins. We measured dN/d{eta} distributions and truncated mean p{sub T} in a region of p{sub T} > P{sub T}{sup cut}, and studied the results in the framework of participant and binary scaling. No clear evidence is observed for participant scaling of charged hadron yield in the measured pT region. The relative importance of hard scattering process is investigated through binary scaling fraction of particle production.
Date: April 15, 2004
Creator: Adams, J.; Aggarwal, M.M.; Ahammed, Z.; Amonett, J.; Anderson, B. D.; Arkhipkin, D. et al.
Object Type: Article
System: The UNT Digital Library
Effect of Radiation on Spinel Ceramics for Permanent Containers for Nuclear Waste Transportation and Storage. (open access)

Effect of Radiation on Spinel Ceramics for Permanent Containers for Nuclear Waste Transportation and Storage.

None
Date: April 30, 2000
Creator: Adams, J.; Cowgill, M.; Moskowitz, P. & Rokhvarger, A.
Object Type: Article
System: The UNT Digital Library
Effect of Radiation on Spinel Ceramics for Permanent Containers for Nuclear Waste Transportation and Storage. (open access)

Effect of Radiation on Spinel Ceramics for Permanent Containers for Nuclear Waste Transportation and Storage.

None
Date: April 30, 2000
Creator: Adams, J.; Cowgill, M.; Moskowitz, P. & Rokhvarger, A.
Object Type: Article
System: The UNT Digital Library
Experimental determination of drag coefficients in low-density polyurethane foam (open access)

Experimental determination of drag coefficients in low-density polyurethane foam

We describe several experiments performed at the LLNL Site 300 firing range and on the LLNL 1/3 scale gun to investigate the deceleration of small projectiles (l {approx} 3-5 [mm]) in low-density foam ({rho} {approx} 0.08-0.32 [g/cm{sup 3}]). The experiments at the firing range researched a passive velocity diagnostic based on Faraday's law of induction, while experiments on the 1/3 scale gun investigated the effects of varying projectile surface area, projectile shape, and foam density on the drag coefficient c{sub d}. Analysis shows that the velocity diagnostic has an uncertainty on the order of 1 percent for projectiles with velocity v {approx} 0.8-1.2 [km/s]. The 1/3 scale gun experiments, dubbed the Krispy Kreme series, included nine shots considering the combinations of 3 projectile surface areas with 3 target densities. The experiments used Tantalum square surface area block projectiles (with an initial velocity v{sub 0} {approx} 1.2 [km/s], a common thickness T = 2.67 [mm], and square side lengths of 3, 4, and 5 [mm]) decelerating in polyurethane foams (with densities {rho}{sub f} of 0.08, 0.16 and 0.32 [g/cm{sup 3}]). Standard fluid models of the Krispy Kreme experiments predict Reynolds numbers Re {approx} 10{sup 5} - 10{sup 6}, Mach numbers Ma …
Date: April 18, 2006
Creator: Adams, M L
Object Type: Report
System: The UNT Digital Library
Tank Characterization Report for Single Shell Tank 241-C-104 (open access)

Tank Characterization Report for Single Shell Tank 241-C-104

Interprets information about the tank answering a series of six questions covering areas such as information drivers, tank history, tank comparisons, disposal implications, data quality and quantity, and unique aspects of the tank.
Date: April 6, 2000
Creator: Adams, M. R.
Object Type: Report
System: The UNT Digital Library
Tank Characterization Report for Single Shell Tank 241-U-102 (open access)

Tank Characterization Report for Single Shell Tank 241-U-102

None
Date: April 11, 2000
Creator: Adams, M. R.
Object Type: Report
System: The UNT Digital Library
Oral History Interview with Marion Adams, April 10, 2009 transcript

Oral History Interview with Marion Adams, April 10, 2009

The National Museum of the Pacific War presents an interview with Marion Adams. Adams was drafted into the Army in July of 1941. He served in the 43rd Engineer Construction Battalion, building roads, hospitals and kitchens. In 1942 he traveled to Australia, where he helped build three airstrips. They traveled to Oro Bay, Papua New Guinea, building railroads and airstrips. Adams was also trained as a medic, serving in the First Aid station. He provides details of both work experiences in engineering and building and assisting the sick and injured. He recalls helping the many wounded in Manila, as well as delivering supplies to the prison camps. He was discharged in June of 1945.
Date: April 10, 2009
Creator: Adams, Marion
Object Type: Sound
System: The Portal to Texas History
Oral History Interview with Marion Adams, April 10, 2009 (open access)

Oral History Interview with Marion Adams, April 10, 2009

The National Museum of the Pacific War presents an interview with Marion Adams. Adams was drafted into the Army in July of 1941. He served in the 43rd Engineer Construction Battalion, building roads, hospitals and kitchens. In 1942 he traveled to Australia, where he helped build three airstrips. They traveled to Oro Bay, Papua New Guinea, building railroads and airstrips. Adams was also trained as a medic, serving in the First Aid station. He provides details of both work experiences in engineering and building and assisting the sick and injured. He recalls helping the many wounded in Manila, as well as delivering supplies to the prison camps. He was discharged in June of 1945.
Date: April 10, 2009
Creator: Adams, Marion
Object Type: Text
System: The Portal to Texas History
Orientation for New State WAP Directors and Staff (open access)

Orientation for New State WAP Directors and Staff

NASCSP has been providing The Orientation for New Weatherization Assistance Program (WAP) State Directors and Staff yearly for the past four years. This report is a general description of the trainings and supporting documentation from the most recent event. The Orientation and Training provides attendees with a comprehensive overview of the WAP from the federal, state, and local perspectives. A variety of presenters make information available on a wide range of subjects deemed necessary to effectively operate the Program. During the first day of training, staff from the Department of Energy WAP office, NASCSP, the National Energy Assistance Director's Association, Economic Opportunity Studies, and Oak Ridge National Laboratory present materials and participate in open discussion with the attendees about the federal program requirements. Some of the day's subjects include: History of the WAP; Funding, Rules, Regulations, and Program Guidance Documents; WAP State Plan Application Process and Submission; Training and Technical Assistance Activity; Administration and Federal/State Monitoring Requirements; and National Significance of WAP and the Political Process. The second day focuses on implementation strategies for the Program. Presenters from state offices and local management provide their perspective on the following subjects: Utility Restructuring Integration Strategies; Program Expansion Issues; Integration of New …
Date: April 14, 2003
Creator: Adams, Robert & Barone, Tracy
Object Type: Report
System: The UNT Digital Library
Quarterly Progress Report - Biological Monitoring Program for East Fork Poplar Creek (open access)

Quarterly Progress Report - Biological Monitoring Program for East Fork Poplar Creek

In May 1985, a National Pollutant Discharge Elimination System (NPDES) permit was issued for the Oak Ridge Y-12 Plant. As a condition of the permit, a Biological Monitoring and Abatement Program (BMAP) was developed to demonstrate that the effluent limitations established for the Y-12 Plant protect the classified uses of the receiving stream (East Fork Poplar Creek; EFPC), in particular, the growth and propagation of aquatic life (Loar et al. 1989). A second objective of the BMAP is to document the ecological effects resulting from the implementation of a water pollution control program designed to eliminate direct discharges of wastewaters to EFPC and to minimize the inadvertent release of pollutants to the environment. Because of the complex nature of the discharges to EFPC and the temporal and spatial variability in the composition of the discharges, a comprehensive, integrated approach to biological monitoring was developed. A new permit was issued to the Y-12 Plant on April 28, 1995 and became effective on July 1, 1995. Biological monitoring continues to be required under the new permit. The BMAP consists of four major tasks that reflect different but complementary approaches to evaluating the effects of the Y-12 Plant discharges on the aquatic integrity …
Date: April 18, 2000
Creator: Adams, S. M.; Christensen, S. W.; Greeley, M. S. Jr.; Hill, W. R.; McCarthy, J. F.; Peterson, M. J. et al.
Object Type: Report
System: The UNT Digital Library

Doctoral Recital: 2003-04-14 – Michael Adduci, oboe

Recital presented at the UNT College of Music Recital Hall in partial fulfillment of the Doctor of Musical Arts (DMA) degree.
Date: April 14, 2003
Creator: Adduci, Michael
Object Type: Sound
System: The UNT Digital Library
Underground Corrosion of Activated Metals in an Arid Vadose Zone Environment (open access)

Underground Corrosion of Activated Metals in an Arid Vadose Zone Environment

The subsurface radioactive disposal site located at the Idaho National Engineering and Environmental Laboratory contains neutron-activated metals from nonfuel nuclear-reactor- core components. A long-term corrosion test is being conducted to obtain site-specific corrosion rates to support efforts to more accurately estimate the transfer of activated elements in an arid vadose zone environment. The tests use nonradioactive metal coupons representing the prominent neutron-activated material buried at the disposal location, namely, Type 304L stainless steel, Type 315L stainless steel, nickel-chromium alloy (UNS NO7718), beryllium, aluminum 6061-T6, and a zirconium alloy, (UNS R60804). In addition, carbon steel (the material presently used in the cask disposal liners and other disposal containers) and a duplex stainless steel (UNS S32550) (the proposed material for the high- integrity disposal containers) are also included in the test program. This paper briefly describes the test program and presents the early corrosion rate results after 1 year and 3 years of underground exposure.
Date: April 1, 2002
Creator: Adler Flitton, Mariana Kay; Mizia, Ronald Eugene & Bishop, Carolyn Wagoner
Object Type: Article
System: The UNT Digital Library
USING WET AIR OXIDATION TECHNOLOGY TO DESTROY TETRAPHENYLBORATE (open access)

USING WET AIR OXIDATION TECHNOLOGY TO DESTROY TETRAPHENYLBORATE

A bench-scale feasibility study on the use of a Wet Air Oxidation (WAO) process to destroy a slurry laden with tetraphenylborate (TPB) compounds has been undertaken. WAO is an aqueous phase process in which soluble and/or insoluble waste constituents are oxidized using oxygen or oxygen in air at elevated temperatures and pressures ranging from 150 C and 1 MPa to 320 C and 22 MPa. The products of the reaction are CO{sub 2}, H{sub 2}O, and low molecular weight oxygenated organics (e.g. acetate, oxalate). Test results indicate WAO is a feasible process for destroying TPB, its primary daughter products [triphenylborane (3PB), diphenylborinic acid (2PB), and phenylboronic acid (1PB)], phenol, and most of the biphenyl byproduct. The required conditions are a temperature of 300 C, a reaction time of 3 hours, 1:1 feed slurry dilution with 2M NaOH solution, the addition of CuSO{sub 4}.5H{sub 2}O solution (500 mg/L Cu) as catalyst, and the addition of 2000 mL/L of antifoam. However, for the destruction of TPB, its daughter compounds (3PB, 2PB, and 1PB), and phenol without consideration for biphenyl destruction, less severe conditions (280 C and 1-hour reaction time with similar remaining above conditions) are adequate.
Date: April 4, 2007
Creator: Adu-Wusu, K; Daniel McCabe, D & Bill Wilmarth, B
Object Type: Article
System: The UNT Digital Library
Report to Congress (open access)

Report to Congress

Final report of the Advisory Commission on Electronic Commerce describing their activities and findings regarding the development of electronic commerce and its impact on the U.S. economy. The report includes sections on the background of electronic commerce, domestic tax issues, and international tax issues.
Date: April 2000
Creator: Advisory Commission on Electronic Commerce
Object Type: Report
System: The UNT Digital Library

Ensemble: 2001-04-21 - African Cultural Festival

Access: Use of this item is restricted to the UNT Community
Ensemble performance at the UNT College of Music Winspear Hall.
Date: April 21, 2001
Creator: African Cultural Festival
Object Type: Sound
System: The UNT Digital Library

Ensemble: 2000-04-22 - African Percussion Ensemble

An African percussion concert performed at the UNT College of Music WInspear Hall.
Date: April 22, 2000
Creator: African Percussion Ensemble
Object Type: Sound
System: The UNT Digital Library

Ensemble: 2008-04-05 – African Cultural Festival

Access: Use of this item is restricted to the UNT Community
Concert presented at the UNT College of Music Concert Hall.
Date: April 5, 2008
Creator: Afrikania Cultural Troupe of Ghana, West Africa
Object Type: Sound
System: The UNT Digital Library
An integrated solution for secure group communication in wide-area networks (open access)

An integrated solution for secure group communication in wide-area networks

Many distributed applications require a secure reliable group communication system to provide coordination among the application components. This paper describes a secure group layer (SGL) which bundles a reliable group communication system, a group authorization and access control mechanism, and a group key agreement protocol to provide a comprehensive and practical secure group communication platform. SGL also encapsulates the standard message security services (i.e, confidentiality, authenticity and integrity). A number of challenging issues encountered in the design of SGL are brought to light and experimental results obtained with a prototype implementation are discussed.
Date: April 1, 2001
Creator: Agarwal, Deborah A.; Chevassut, Olivier; Thompson, Mary & Tsudik, Gene
Object Type: Article
System: The UNT Digital Library
A DATA-CENTERED COLLABORATION PORTAL TO SUPPORT GLOBAL CARBON-FLUX ANALYSIS (open access)

A DATA-CENTERED COLLABORATION PORTAL TO SUPPORT GLOBAL CARBON-FLUX ANALYSIS

Carbon-climate, like other environmental sciences, has been changing. Large-scalesynthesis studies are becoming more common. These synthesis studies are often conducted by science teams that are geographically distributed and on datasets that are global in scale. A broad array of collaboration and data analytics tools are now available that could support these science teams. However, building tools that scientists actually use is hard. Also, moving scientists from an informal collaboration structure to one mediated by technology often exposes inconsistencies in the understanding of the rules of engagement between collaborators. We have developed a scientific collaboration portal, called fluxdata.org, which serves the community of scientists providing and analyzing the global FLUXNET carbon-flux synthesis dataset. Key things we learned or re-learned during our portal development include: minimize the barrier to entry, provide features on a just-in-time basis, development of requirements is an on-going process, provide incentives to change leaders and leverage the opportunity they represent, automate as much as possible, and you can only learn how to make it better if people depend on it enough to give you feedback. In addition, we also learned that splitting the portal roles between scientists and computer scientists improved user adoption and trust. The fluxdata.org portal …
Date: April 7, 2009
Creator: Agarwal, Deborah A.; Humphrey, Marty; Beekwilder, Norm; Jackson, Keith; Goode, Monte & van Ingen, Catharine
Object Type: Article
System: The UNT Digital Library
The Eastern Statesman (Wilburton, Okla.), Vol. 81, No. 12, Ed. 1 Tuesday, April 15, 2003 (open access)

The Eastern Statesman (Wilburton, Okla.), Vol. 81, No. 12, Ed. 1 Tuesday, April 15, 2003

Biweekly student newspaper from Eastern Oklahoma State College in Wilburton, Oklahoma that includes local, state, and campus news along with advertising.
Date: April 15, 2003
Creator: Agent, Alicia
Object Type: Newspaper
System: The Gateway to Oklahoma History