Measurement of the Inclusive and Dijet Cross-sections of b-jets in pp Collisions at sqrt(s) = 7 TeV with the ATLAS Detector (open access)
Fermi LAT Observations of Cosmic-Ray Electrons From 7 GeV to 1 TeV (open access)

Fermi LAT Observations of Cosmic-Ray Electrons From 7 GeV to 1 TeV

None
Date: May 28, 2013
Creator: Ackermann, M.; Ajello, M.; Atwood, W. B.; Baldini, L.; Ballet, J.; Barbiellini, G. et al.
System: The UNT Digital Library
PILOT-SCALE HYDRAULIC TESTING OF RESORCINOL FORMALDEHYDE ION EXCHANGE RESIN (open access)

PILOT-SCALE HYDRAULIC TESTING OF RESORCINOL FORMALDEHYDE ION EXCHANGE RESIN

Savannah River National Laboratory (SRNL) performed pilot-scale hydraulic/chemical testing of spherical resorcinol formaldehyde (RF) ion exchange (IX) resin for the River Protection Project-Hanford Tank Waste Treatment & Immobilization Plant (WTP) Project. The RF resin hydraulic cycle testing was conducted in two pilot-scale IX columns, 1/4 and 1/2 scale. A total of twenty-three hydraulic/chemical cycles were successfully completed on the spherical RF resin. Sixteen of these cycles were completed in the 24-inch IX Column (1/2 scale column). Hydraulic testing showed that the permeability of the RF resin remained essentially constant, with no observed trend in the reduction of the permeability as the number of cycles increased. The permeability during the pilot-scale testing was 3 times better than the design requirements of the WTP full-scale IX system. The RF resin bed showed no tendency to form fissures or pack more densely as the number of cycles increased. Particle size measurements of the RF resin showed no indication of particle size change (for a given chemical) with cycles and essentially no fines formation. The permeability of the resin bed was uniform with respect to changes in bed depth. Upflow Regeneration and Simulant Introduction in the IX columns revealed another RF resin benefit; negligible …
Date: May 28, 2009
Creator: Adamson, D.
System: The UNT Digital Library
Dark Matter Search Results Using the Silicon Detectors of CDMS II (open access)

Dark Matter Search Results Using the Silicon Detectors of CDMS II

None
Date: May 28, 2013
Creator: Agnese, R.; Ahmed, Z.; Anderson, A. J.; Arrenberg, S.; Balakishiyeva, D.; Thakur, R. Basu et al.
System: The UNT Digital Library
Silicon Detector Results from the First Five-Tower Run of CDMS II (open access)

Silicon Detector Results from the First Five-Tower Run of CDMS II

None
Date: May 28, 2013
Creator: Agnese, R.; Ahmed, Z.; Anderson, A. J.; Arrenberg, S.; Balakishiyeva, D.; Thakur, R. et al.
System: The UNT Digital Library
Demonstration of Surface Electron Rejection with Interleaved Germanium Detectors for Dark Matter Search (open access)

Demonstration of Surface Electron Rejection with Interleaved Germanium Detectors for Dark Matter Search

Measures charge and athermal phonons from each particle interaction,which provides excellent discrimination between electron recoils and nuclear recoils.
Date: May 28, 2013
Creator: Agnese, R.; Anderson, A. J.; Balakishiyeva, D.; Thakur, R.; Bauer, D. A.; Borgland, A. et al.
System: The UNT Digital Library
Performance of two-phase nozzles for total flow geothermal impulse turbines (open access)

Performance of two-phase nozzles for total flow geothermal impulse turbines

None
Date: May 28, 1975
Creator: Alger, T.W.
System: The UNT Digital Library
Comparison of gridded versus observation data to initialize ARAC dispersion models for the Algeciras, Spain steel mill CS-137 release (open access)

Comparison of gridded versus observation data to initialize ARAC dispersion models for the Algeciras, Spain steel mill CS-137 release

On May 30, 1998 scrap metal containing radioactive Cesium-137 (Cs-137) was accidentally melted in a furnace at the Acerinox steel mill in Algeciras, Spain. Cs-137 was released from the mill's smokestack, and spread across the western Mediterranean Sea to France and Italy and beyond. The first indication of the release was radiation levels up to 1000 times background reported by Swiss, French, and Italian authorities during the following two weeks. Initially no elevated radiation levels were detected over Spain. A release of hazardous material to the atmosphere is the type of situation the Atmospheric Release Advisory Capability (ARAC) emergency response organization was designed to address. The amount and exact time of the release were unknown, though the incident was thought to have taken place during the last week in May. Using air concentration measurements supplied by colleagues of ARAC in Spain, France, Switzerland, Italy, Sweden, Russia and the European Union, ARAC meteorologists estimated the magnitude and timing of the release (Vogt, 1999). Correctly locating the downwind footprint is the most important goal of emergency response modeling. In this study, we compare predicted results for the Algeciras event based on four wind data sources: (1) US Navy Operational Global Atmospheric Prediction …
Date: May 28, 1999
Creator: Aluzzi, F J; Pace, J C; Pobanz, B M & Vogt, P J
System: The UNT Digital Library
Issues related to choosing a guard force structure (open access)

Issues related to choosing a guard force structure

None
Date: May 28, 1975
Creator: Averbach, C.; Cusack, J.; Green, L.; Higinbotham, W.; Indusi, J.; Marcuse, W. et al.
System: The UNT Digital Library
Investigation and simulation of muon cooling rings with tilted solenoids (open access)

Investigation and simulation of muon cooling rings with tilted solenoids

Alternating solenoid focused muon cooling ring without special bending magnets is considered and investigate in detail. Both fringe field between solenoid coils with opposite directed current, and an inclination of the coils in vertical plane are used to provide a bending and closing of the particle trajectories. Realistic (Maxwellian) magnetic field is calculated and used for a simulation. Methodic is developed and applied to find closed orbit at any energy, dispersion, region of stability, and other conventional accelerator characteristics. Earlier proposed RFOFO cooling ring with 200 MHz RF system and liquid hydrogen absorbers is investigated in detail. After an optimization, normalized 6D emittance about 20 mm{sup 3} and transmission 57% are obtained.
Date: May 28, 2003
Creator: Balbekov, Valeri I.
System: The UNT Digital Library
Lithium lenses based muon cooling channel (open access)

Lithium lenses based muon cooling channel

A linear ionization cooling channel for neutrino factory or muon collider is considered. It includes short Li lenses, matching solenoids, and 201 MHz RF cavities. The basic challenge is a suppression of chromatic effects in a wide energy range typical for muon beams. A special lattice is proposed to reach this, and methodic of an optimization is developed to minimize the chromatic aberrations by suppression of several betatron resonances. The most engineering constraint is a high field of matching solenoids. A channel with less of 10 T field is considered in detail. It is capable to cool transverse emittance of a beam from 2-3 mm to 0.5 mm at the channel length of about 130 m. Because there is no emittance exchange, longitudinal emittance increases in the process from 10 to 20 mm at transmission of about 90%.
Date: May 28, 2003
Creator: Balbekov, Valeri I.
System: The UNT Digital Library
Solubility and Reaction Rates of Aluminum Solid Phases Under Geothermal Conditions (open access)

Solubility and Reaction Rates of Aluminum Solid Phases Under Geothermal Conditions

Experimental studies involving equilibrium solubility and dissolution/precipitation rates were initiated on aluminum hydroxide phases prevalent under geothermal reservoir conditions. A large capacity, hydrogen-electrode concentration cell (HECC) was constructed specifically for this purpose.
Date: May 28, 2000
Creator: Benezeth, P.; Palmer, D. A.; Wesolowski, D. J. & Anovitz, L. M.
System: The UNT Digital Library
Joint inversion of geophysical data for site characterization and restoration monitoring (open access)

Joint inversion of geophysical data for site characterization and restoration monitoring

The purpose of this project is to develop a computer code for joint inversion of seismic and electrical data, to improve underground imaging for site characterization and remediation monitoring. The computer code developed in this project will invert geophysical data to obtain direct estimates of porosity and saturation underground, rather than inverting for seismic velocity and electrical resistivity or other geophysical properties. This is intended to be a significant improvement in the state-of-the-art of underground imaging, since interpretation of data collected at a contaminated site would become much less subjective. Potential users include DOE scientists and engineers responsible for characterizing contaminated sites and monitoring remediation of contaminated sites. In this three-year project, we use a multi-phase approach consisting of theoretical and numerical code development, laboratory investigations, testing on available laboratory and borehole geophysics data sets, and a controlled field experiment, to develop practical tools for joint electrical and seismic data interpretation.
Date: May 28, 1998
Creator: Berge, P. A.
System: The UNT Digital Library
Mapping the geometry of the F4 group (open access)

Mapping the geometry of the F4 group

In this paper, we present a construction of the compact form of the exceptional Lie group F4 by exponentiating the corresponding Lie algebra f4. We realize F4 as the automorphisms group of the exceptional Jordan algebra, whose elements are 3 x 3 Hermitian matrices with octonionic entries. We use a parametrization which generalizes the Euler angles for SU(2) and is based on the fibration of F4 via a Spin(9) subgroup as a fiber. This technique allows us to determine an explicit expression for the Haar invariant measure on the F4 group manifold. Apart from shedding light on the structure of F4 and its coset manifold OP2 = F4/Spin(9), the octonionic projective plane, these results are a prerequisite for the study of E6, of which F4 is a (maximal) subgroup.
Date: May 28, 2007
Creator: Bernardoni, Fabio; Cacciatori, Sergio L; Scotti, Antonio & Cerchiai, Bianca L.
System: The UNT Digital Library
Commentary: Risk Management and Reliability Design for Buildings (open access)

Commentary: Risk Management and Reliability Design for Buildings

Where there is a significant actuarial basis for decision making (e.g., the occurrence of fires in single-family dwellings), there is little incentive for formal risk management. Formal risk assessments are most useful in those cases where the value of the structure is high, many people may be affected, the societal perception of risk is high, consequences of a mishap would be severe, and the actuarial uncertainty is large. For these cases, there is little opportunity to obtain the necessary experiential data to make informed decisions, and the consequences in terms of money, lives, and societal confidence are severe enough to warrant a formal risk assessment. Other important factors include the symbolic value of the structure and vulnerability to single point failures. It is unlikely that formal risk management and assessment practices will or should replace the proven institutions of building codes and engineering practices. Nevertheless, formal risk assessment can provide valuable insights into the hazards threatening high-value and high-risk (perceived or actual) buildings and structures, which can in turn be translated into improved public health, safety, and security. The key is to choose and apply the right assessment tool to match the structure in question. Design-for-reliability concepts can be applied …
Date: May 28, 1999
Creator: Berry, Dennis L.; Cranwell, Robert M. & Hunter, Regina L.
System: The UNT Digital Library
Generation of High Brightness X-Rays with the PLEIADES Thomson X-Ray Source (open access)

Generation of High Brightness X-Rays with the PLEIADES Thomson X-Ray Source

The use of short laser pulses to generate high peak intensity, ultra-short x-ray pulses enables exciting new experimental capabilities, such as femtosecond pump-probe experiments used to temporally resolve material structural dynamics on atomic time scales. PLEIADES (Picosecond Laser Electron InterAction for Dynamic Evaluation of Structures) is a next generation Thomson scattering x-ray source being developed at Lawrence Livermore National Laboratory (LLNL). Ultra-fast picosecond x-rays (10-200 keV) are generated by colliding an energetic electron beam (20-100 MeV) with a high intensity, sub-ps, 800 nm laser pulse. The peak brightness of the source is expected to exceed 10{sup 20} photons/s/0.1% bandwidth/mm2/mrad2. Simulations of the electron beam production, transport, and final focus are presented. Electron beam measurements, including emittance and final focus spot size are also presented and compared to simulation results. Measurements of x-ray production are also reported and compared to theoretical calculations.
Date: May 28, 2003
Creator: Brown, W J; Anderson, S G; Barty, C P J; Crane, J K; Cross, R R; Fittinghoff, D N et al.
System: The UNT Digital Library
Movable Genetic Elements: Detection of Changes in Maize DNA at the Shrunken Locus Due to the Intervention of Ds Elements (open access)

Movable Genetic Elements: Detection of Changes in Maize DNA at the Shrunken Locus Due to the Intervention of Ds Elements

This report describes our initial attempts at the molecular characterization of a maize controlling element. We have prepared a cDNA probe and used it to detect changes at a locus where Ds elements are found. Evidence of their presence are indicated by changes in the restriction patterns, but there is as yet no information on the physical nature of the controlling elements nor on the kinds of rearrangements they cause.
Date: May 28, 1980
Creator: Burr, B. & Burr, F.A.
System: The UNT Digital Library
Non-Linear Dose-Response Relationships in Biology, Toxicology and Medicine - An International Conference (open access)

Non-Linear Dose-Response Relationships in Biology, Toxicology and Medicine - An International Conference

Conference abstract book contains seven sections: Plenary-4 abstracts; Chemical-9 abstracts; Radiation-7 abstracts; Ultra Low Doses and Medicine-6 abstracts; Biomedical-11 abstracts; Risk Assessment-5 abstracts and Poster Sessions-25 abstracts. Each abstract was provided by the author/presenter participating in the conference.
Date: May 28, 2002
Creator: Calabrese, Edward J. & Kostecki, Paul T.
System: The UNT Digital Library
Altering the Equilibrium Condition in Sr-Doped Lanthanum Manganite (open access)

Altering the Equilibrium Condition in Sr-Doped Lanthanum Manganite

The material of choice for a solid oxide fuel cell cathode based on a yttria-stabilized zirconia (YSZ) electrolyte is doped lanthanum manganite, (La, Sr)MnO{sub 3}. It excels at many of the attributes necessary for a system to work at the required operating temperature and is flexible enough to allow for materials optimization. Although strontium-doping increases the electronic conductivity of the material, the ionic conductivity of the material remains negligible under operating conditions. Studies have shown that the internal equilibrium of the material heavily favors oxidation of the manganese and rather than the loss of lattice oxygen as a charge compensation mechanism. This lack of oxygen vacancies in the structure retards the ability of the material to conduct oxygen ions; thus the optimized system requires a large number of engineered triple point boundary locations to work efficiently. We have successfully doped the host LSM lattice to alter the interred equilibrium of the material to increase its ionic conductivity and thus lower the cathodic overpotential of the system. Our presentation will discuss these new materials, the results of cell tests, and a number of characterization experiments performed.
Date: May 28, 1999
Creator: Carter, J. D.; Krumpelt, M.; Vaughey, J. & Wang, X.
System: The UNT Digital Library
Broadband diffractive lens (open access)

Broadband diffractive lens

Significant progress has been made toward solving the century-old problem of chromatic aberrations in diffractive optics. Our approach exploits modern materials and microfabrication technology and is very different from the purely diffractive strategy,'' which is commonly employed and which results in multiple diffractive elements separated by a finite distance. We have developed a Fresnel zone plate lens comprised of a serial stack of patterned minus-filters which allows broadband radiation to be focused (or imaged) without longitudinal or transverse chromatic aberrations. 7 refs., 4 figs.
Date: May 28, 1991
Creator: Ceglio, N. M.; Hawryluk, A. M.; London, R. A.; Seppala, L. G. (Lawrence Livermore National Lab., CA (USA)) & Gaines, D. P. (Brigham Young Univ., Provo, UT (USA))
System: The UNT Digital Library
Studies of the top quark at the Tevatron (open access)

Studies of the top quark at the Tevatron

We report on studies of the top quark, beyond the measurements of its mass and produciton cross section, which have been carried out recently by the CDF and D0 collaborations, based on {approximately}110{+-}6 pb{sup -1} of proton-antiproton collisions at a center-of-mass energy of 1.8 TeV. Each experiment has searched for t{yields}H{sup +}b decays and, from the lack of observable signal, excluded previously unexplored regions of the [M{sub H+},tan{beta}] parameter space. D0 has studied the correlation between the spin states of pair-produced top quarks, and CDF has studied the helicity of the W bosons produced in the decay of top quarks. Within large statistical uncertainties, both measurements agree with predictions of the standard model.
Date: May 28, 1999
Creator: Chakraborty, Dhiman
System: The UNT Digital Library
Vlasov simulation of the parametric instability of ion acoustic waves (open access)

Vlasov simulation of the parametric instability of ion acoustic waves

None
Date: May 28, 2013
Creator: Chapman, T. D.; Berger, R. L.; Cohen, B. I.; Williams, E. A. & Brunner, S.
System: The UNT Digital Library
Linearization of the Fermilab recycler high level RF (open access)

Linearization of the Fermilab recycler high level RF

In studying the Recycler high level RF, it was found that at 89 kHz, the lowest frequency required by the system, some nonlinearities in magnitude and phase were discovered. The visible evidence of this was that beam injected in a barrier bucket had a definite slope at the top. Using a network analyzer, the S-parameter S{sub 21} was realized for the overall system and from mathematical modeling a second order numerator and denominator transfer function was found. The inverse of this transfer function gives their linearization transfer function. The linearization transfer function was realized in hardware by summing a high pass, band pass and low pass filter together. The resulting magnitude and phase plots, along with actual beam response will be shown.
Date: May 28, 2003
Creator: Dey, Joseph E; Kubicki, Tom & Reid, John
System: The UNT Digital Library