Degree Level

Charm production physics from Fermilab fixed-target experiments (open access)

Charm production physics from Fermilab fixed-target experiments

Recent analyses of charm quark production mechanisms from Fermilab fixed-target experiments are summarized. Measurements of single inclusive differential cross sections for hadroproduced and photoproduced D mesons are compared to next-to-leading order QCD calculations. New data from hadroproduction and previous photoproduction measurements of charm meson pair correlations are compared to NLO calculations and also to parton shower Monte Carlo models. Nonperturbative effects, such as intrinsic k{sub t} and fragmentation, are seen to play an important role in most of these comparisons. Results on charm production asymmetries in both hadroproduction and photoproduction are summarized.
Date: May 1, 1995
Creator: Gardner, R.
Object Type: Report
System: The UNT Digital Library
7th International Workshop on the Identification of Transcribed Sequences. Beyond the Identification of Transcribed Sequences (open access)

7th International Workshop on the Identification of Transcribed Sequences. Beyond the Identification of Transcribed Sequences

The Seventh Annual Human Genome Conference: Beyond the Identification of Transcribed Sequences (BITS) was held November 16-19, 1997 at the Asilomar Conference Center in Monterey, California. The format for the meeting was a combination of oral presentations, group discussions and poster sessions. The original workshop was held to discuss methodologies for the identification of transcribed sequences in mammalian genomes. Over the years, the focus of the workshops has gradually shifted towards functional analysis, with the most dramatic change in emphasis at this meeting, as reflected in the modest change in the workshop title. Topics presented and discussed included: (1) large scale expression and mutational analysis in yeast, C. elegans, Drosophila and zebrafish, (2) comparative mapping of zebrafish, chicken and Fugu; (3) functional analysis in mouse using promoter traps, mutational analysis of biochemical pathways, and Cre/lox constructs; (4) construction of 5 foot end and complete cDNA libraries; (5) expression analysis in mammalian organisms by array screening and differential display; (6) genome organization as determined by detailed transcriptional mapping and genomic sequence analysis; (7) analysis of genomic sequence, including gene and regulatory sequence predictions, annotation of genomic sequence, development of expression databases and verification of sequence analysis predictions; and (8) structural/functional relationships …
Date: November 19, 1997
Creator: Gardner, Kathleen
Object Type: Report
System: The UNT Digital Library
Underprivileged Students and Institutions of Higher Education; Selected References (open access)

Underprivileged Students and Institutions of Higher Education; Selected References

This report consists of selected references regarding the topic of underprivileged students and institutions of higher education.
Date: February 28, 1969
Creator: Gardner, Mindi
Object Type: Report
System: The UNT Digital Library
Injection of large transverse emittance EBIS beams in booster (open access)

Injection of large transverse emittance EBIS beams in booster

During the commissioning of EBIS beams in Booster in November 2010 and in April, May and June 2011, it was found that the transverse emittances of the EBIS beams just upstream of Booster were much larger than expected. Beam emittances of 11{pi} mm milliradians had been expected, but numbers 3 to 4 times larger were measured. Here and throughout this note the beam emittance, {pi}{epsilon}{sub 0}, is taken to be the area of the smallest ellipse that contains 95% of the beam. We call this smallest ellipse the beam ellipse. If the beam distribution is gaussian, the rms emittance of the distribution is very nearly one sixth the area of the beam ellipse. The normalized rms emittance is the rms emittance times the relativistic factor {beta}{gamma} = 0.06564. This amounts to 0.12{pi} mm milliradians for the 11{pi} mm milliradian beam ellipse. In [1] we modeled the injection and turn-by-turn evolution of an 11{pi} mm milliradian beam ellipse in the horizontal plane in Booster. It was shown that with the present injection system, up to 4 turns of this beam could be injected and stored in Booster without loss. In the present note we extend this analysis to the injection of …
Date: October 10, 2011
Creator: Gardner, C.
Object Type: Report
System: The UNT Digital Library
A MACRO GRAIN SIZE TECHNIQUE FOR URANIUM (open access)

A MACRO GRAIN SIZE TECHNIQUE FOR URANIUM

None
Date: February 1, 1956
Creator: Gardner, H.R.
Object Type: Report
System: The UNT Digital Library
Studies of Charged Particle Distributions in an Electrostatic Confinement System. Progress Report, 1 November 1971--31 January 1976 (open access)

Studies of Charged Particle Distributions in an Electrostatic Confinement System. Progress Report, 1 November 1971--31 January 1976

Microwave cavity techniques were used to measure electron density in a spherical, inertial-electrostatic confinement device using six ion guns. The density was roughly proportional to ion current (1 to 17 mA) and decreased somewhat with increasing ion energy (10 to 37 keV). With D$sub 2$ pressure decrease from 10 to 3 mTorr, n/sub e/ decreased faster than linearly and below approximately 3 mTorr decreased linearly with pressure down to the lowest pressure of 0.4 mTorr. At 1 mTorr and 10 mA, measurements (with poor spatial resolution) were consistent with 10$sup 10$ total electrons and a central n/sub e/ of 10$sup 9$ electrons/cm$sup 3$. Neutron flux (at 50 keV) was about one sixth that of Hirsch (J. Appl. Phys. 38, 4522 (1967)). Six- vs. three-gun operation showed a small enhancement of both n/sub e/ and neutron flux that may indicate some particle trapping.
Date: January 1, 1976
Creator: Gardner, A. L.
Object Type: Report
System: The UNT Digital Library
Indium donor complexes with cation vacancies in CdTe and ZnSe (open access)

Indium donor complexes with cation vacancies in CdTe and ZnSe

Very dilute (10{sub 12} cm{sup {minus}3}) indium donors in CdTe and ZnSe powders and in CdTe single crystals were investigated using {sup 111}In Perturbed angular correlation spectroscopy. Most indium atoms are in uncomplexed sites but can form weakly-bound complexes with native defects in very defective material. The only complex observed in CdTe is an indium-Cd vacancy pair. The CdTe in which these pairs occur is apparently n-type, most Cd vacancies are free and doubly-charged, and the binding energy with indium is 0.15 eV. In ZnSe, indium can pair with a Zn vacancy or with some other presently unidentified defect. These complexes form in ZnSe containing large concentrations of both free Zn vacancies and complexes of Zn vacancies with other defects. In CdTe, the pair formation equilibration time constant is two days at 15C,an implication that Cd vacancies are mobile at room temperature. Lattice relaxation around a Cd vacancy in CdTe was probed by single crystal PAC experiments.
Date: November 1, 1993
Creator: Griffith, J. W.; Lundquist, R.; Platzer, R.; Gardner, J. A.; Karczewski, G. & Furdyna, J. K.
Object Type: Article
System: The UNT Digital Library
Particle Trajectories in Homogeneous Magnetic Field with Linear Time Dependence (open access)

Particle Trajectories in Homogeneous Magnetic Field with Linear Time Dependence

Abstract: "Formulas are derived for the trajectory of a charged particle in a magnetic field which is a linear function of time. Graphs of certain functions are presented, by means of which a trajectory with given initial position and velocity may be plotted."
Date: August 9, 1955
Creator: Gardner, Clifford S.
Object Type: Report
System: The UNT Digital Library
Recess Appointments Made by President George W. Bush (open access)

Recess Appointments Made by President George W. Bush

None
Date: April 15, 2009
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Neutron reactions on $sup 239$U (open access)

Neutron reactions on $sup 239$U

None
Date: April 24, 1975
Creator: Gardner, D. G.
Object Type: Report
System: The UNT Digital Library
GRAIN REFINEMENT PRODUCED BY AN ALPHA PHASE ANNEAL OF BETA PHASE HEAT TREATED AND WATER QUENCHED URANIUM (open access)

GRAIN REFINEMENT PRODUCED BY AN ALPHA PHASE ANNEAL OF BETA PHASE HEAT TREATED AND WATER QUENCHED URANIUM

During an experiment involving alpha phase annealing (at 610 to 655 deg C for 5 and 10 min) of beta-quenched uranium, it was determined that the relatively coarse, irregular shaped grains (0.08 to 0.150 mm in diameter) in the beta-quenched structure, were replaced by fine equiaxed grains (0.04 to 0.09 mm in diameter). (auth)
Date: January 1, 1955
Creator: Gardner, H.R.
Object Type: Report
System: The UNT Digital Library
Preliminary report on the tensile properties of plutonium (open access)

Preliminary report on the tensile properties of plutonium

Preliminary data have been obtained on the effect of temperature on the tensile properties of a Pu-0.9 w/o Ga delta stabilized alloy. Contoured castings for tensile specimen fabrication were obtained by pouring in vacuo from 900 {degrees}C into a MgO coated graphite mold heated to 475-500 {degrees}C.
Date: March 8, 1962
Creator: Gardner, H. R.
Object Type: Report
System: The UNT Digital Library
FY11 Report on Metagenome Analysis using Pathogen Marker Libraries (open access)

FY11 Report on Metagenome Analysis using Pathogen Marker Libraries

None
Date: June 2, 2011
Creator: Gardner, S.; Allen, J.; McLoughlin, K. & Slezak, T.
Object Type: Report
System: The UNT Digital Library
Analysis of Fragmentation and Resulting Shrapnel Penetration of Naturally Fragmenting Cylindrical Bombs (open access)

Analysis of Fragmentation and Resulting Shrapnel Penetration of Naturally Fragmenting Cylindrical Bombs

Fragmentation of exploding cylinders and penetration mechanics of surrounding vessel walls were examined and a qualitative understanding was achieved. This understanding provided a basis for making simplifying approximations and assumptions that aided in creating a shrapnel penetration model. Several mathematical models were discussed, and results from 6 cylinder tests were analyzed in order to select a model that best represented the data. It was determined that the overall best mathematical model to predict shrapnel penetration uses the modified Gurney equation to calculate fragment velocity, the Mott equation to calculate largest fragment weight, and the Christman/Gehring equation to calculate penetration depth.
Date: August 1, 2000
Creator: Gardner, S. E.
Object Type: Report
System: The UNT Digital Library
Diagnostic Measurements of a Highly Ionized, Steady-state Plasma (open access)

Diagnostic Measurements of a Highly Ionized, Steady-state Plasma

This paper is primarily intended to give an account of a few of the diagnostic techniques that have been applied to a highly ionized, steady-state helium plasma at the Lawrence Radiation Laboratory. However, to establish a proper perspective it will first be well to describe briefly the system in which the plasma is generated and studied.
Date: 1960
Creator: Gardner, Andrew L.
Object Type: Report
System: The UNT Digital Library
Preliminary Results on the Kinetic Behavior of Water Boiler Reactors (open access)

Preliminary Results on the Kinetic Behavior of Water Boiler Reactors

None
Date: April 15, 1957
Creator: Hetrick, D. L.; Flora, J. W.; Gardner, E. L.; Moskowitz, B. R.; Muller, D. R.; Remley, M. E. et al.
Object Type: Report
System: The UNT Digital Library
Calculational tools for the evaluation of nuclear cross-section and spectra data (open access)

Calculational tools for the evaluation of nuclear cross-section and spectra data

A technique based on discrete energy levels rather than energy level densities is presented for nuclear reaction calculations. The validity of the technique is demonstrated via theoretical and experimental agreement for cross sections, isomer-ratios and gamma-ray strength functions. 50 refs., 7 figs. (WRF)
Date: May 7, 1985
Creator: Gardner, M.A.
Object Type: Article
System: The UNT Digital Library
Mollusca From the Miocene and Lower Pliocene of Virginia and North Carolina: Part 1. Pelecypoda (open access)

Mollusca From the Miocene and Lower Pliocene of Virginia and North Carolina: Part 1. Pelecypoda

Abstract: A brief sketch of the stratigraphy of the Miocene of Virginia and the Miocene and Pliocene of North Carolina was prepared by Dr. W. C. Mansfield before his death in July 1939. His purpose was "to provide a background of formational nomenclature" for the taxonomic treatment of the molluscan faunas. The physical nature and distribution of the upper Tertiary formations within those States are discussed, characteristic sections given, and diagnostic molluscan species listed. Part 1 of the systematic report covers the Pelecypoda. A monographic treatment is not attempted, but 132 previously known species are considered, and 62 new species and subspecies are described and figured.
Date: 1943
Creator: Gardner, Julia Anna
Object Type: Report
System: The UNT Digital Library
Scientific drilling in the Valles caldera magma-hydrothermal system, New Mexico (open access)

Scientific drilling in the Valles caldera magma-hydrothermal system, New Mexico

None
Date: April 1, 1994
Creator: Goff, F.; Gardner, J. N.; Heiken, G. & Hulen, J. B.
Object Type: Report
System: The UNT Digital Library
Recent developments in nuclear reaction theories and calculations (open access)

Recent developments in nuclear reaction theories and calculations

A brief review is given of some recent developments in the fields of optical model potentials; level densities; and statistical model, precompound, and direct reaction codes and calculations. Significant developments have occurred in all of these fields since the 1977 Conference on Neutron Cross Sections, which will greatly enhance the ability to calculate high-energy neutron-induced reaction cross sections in the next few years. 11 figures, 3 tables.
Date: May 5, 1980
Creator: Gardner, D. G.
Object Type: Article
System: The UNT Digital Library
Methods and procedures for evaluation of neutron-induced activation cross sections (open access)

Methods and procedures for evaluation of neutron-induced activation cross sections

One cannot expect measurements alone to supply all of the neutron-induced activation cross-section data required by the fission reactor, fusion reactor, and nuclear weapons development communities, given the wide ranges of incident neutron energies, the great variety of possible reaction types leading to activation, and targets both stable and unstable. Therefore, the evaluator must look to nuclear model calculations and systematics to aid in fulfilling these cross-section data needs. This review presents some of the recent developments and improvements in the prediction of neutron activation cross sections, with specific emphasis on the use of empirical and semiempirical methods. Since such systematics require much less nuclear informaion as input and much less computational time than do the multistep Hauser-Feshbach codes, they can often provide certain cross-section data at a sufficient level of accuracy within a minimum amount of time. The cross-section information that these systematics can and cannot provide and those cases in which they can be used most reliably are discussed.
Date: September 1, 1981
Creator: Gardner, M.A.
Object Type: Article
System: The UNT Digital Library
Statistical vs valence neutron neutron capture in /sup 98/Mo (open access)

Statistical vs valence neutron neutron capture in /sup 98/Mo

It has often been reported that, in mass regions corresponding to peaks in the neutron strength function, nonstatistical mechanisms contribute a significant or even major portion of the average radiation width in the beginning of the resonance region. This could severely limit the possibility of calculating caputure cross sections for targets where experimental data are lacking, because such direct effects are sensitive to the detailed nuclear level structure in the daughter nucleus. The reaction /sup 98/Mo+n was examined for neutrons in the 1 keV to 3 MeV energy range, because this case is often cited as one of the clearest examples of valence neutron capture effects. Preliminary calculations are presented which suggest that these nonstatistical effects rapidly disappear when measurements from even a small number of resonances are averaged.
Date: June 19, 1981
Creator: Gardner, D. G.
Object Type: Article
System: The UNT Digital Library
Current status of fast-neutron-capture calculations (open access)

Current status of fast-neutron-capture calculations

This work is primarily concerned with the calculation of neutron capture cross sections and capture gamma-ray spectra, in the framework of the Hauser-Feshbach statistical model and for neutrons from the resonance region up to several MeV. An argument is made that, for applied purposes such as constructing evaluated cross-section libraries, nonstatistical capture mechanisms may be completely neglected at low energies and adequately approximated at high energies in a simple way. The use of gamma-ray strength functions to obtain radiation widths is emphasized. Using the reaction /sup 89/Y + n as an example, the problems encountered in trying to construct a case that could be run equivalently on two different nuclear reaction codes are illustrated, and the effects produced by certain parameter variations are discussed.
Date: April 15, 1982
Creator: Gardner, D. G.
Object Type: Article
System: The UNT Digital Library
Reservoir enhancement on the impermeable margins of productive geothermal fields (open access)

Reservoir enhancement on the impermeable margins of productive geothermal fields

This is the final report of a one-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos national Laboratory (LANL). The overall goal of the project was to evaluate the performance of Los Alamos technology in selected geothermal fields, to adapt the technology to the existing industry infrastructure where necessary, and to facilitate its application through demonstration and communication. The primary specific objective was to identify, collaborate, and partner with geothermal energy- producing companies in an evaluation of the application of Los Alamos microseismic mapping technology for locating fracture permeability in producing geothermal fields.
Date: January 1, 1997
Creator: Goff, S.; Gardner, J.; Dreesen, D. & Whitney, E.
Object Type: Report
System: The UNT Digital Library