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HYDROTHERMAL ALTERATION OF CONCRETE: YUCCA MOUNTAIN REPOSITORY ANALOGUES (open access)

HYDROTHERMAL ALTERATION OF CONCRETE: YUCCA MOUNTAIN REPOSITORY ANALOGUES

None
Date: October 1, 1997
Creator: A.MEIKE, K.B. MYERS
Object Type: Report
System: The UNT Digital Library
Nonforward parton distributions (open access)

Nonforward parton distributions

Applications of perturbative QCD to deeply virtual Compton scattering and hard exclusive electroproduction processes require a generalization of usual parton distributions for the case when long-distance information is accumulated in nonforward matrix elements <p{prime}{vert_bar}O(0,x){vert_bar}p> of quark and gluon light-cone operators. They describe two types of nonperturbative functions parameterizing such matrix elements: double distributions F(x,y;t) and nonforward distribution functions F{_}/zeta (X;t), discuss their spectral properties, evolution equations which they satisfy, basic uses and general aspects of factorization for hard exclusive processes.
Date: April 1, 1997
Creator: A.Radyushkin
Object Type: Article
System: The UNT Digital Library
Dissolution of low-enriched UO{sub 2}/Al dispersion plates in alkaline peroxide solution. (open access)

Dissolution of low-enriched UO{sub 2}/Al dispersion plates in alkaline peroxide solution.

Some conclusions from this report are: (1) A UO{sub 2}/Al dispersion target can be successfully dissolved in alkaline peroxide solutions; (2) after destruction of the peroxide recovery of the {sup 99}Mo would be nearly identical to existing processes using basic dissolution; (3) a low-enriched UO{sub 2}/Al dispersion targets could potentially be used for the production of {sup 99}Mo; and (4) punched cores from a UO{sub 2}/Al dispersion target will be irradiated to low-level burnup and effects of this LEU target on the recovery of {sup 99}Mo will be investigated. A commercial partner will be sought for full scale demonstrations.
Date: October 21, 1997
Creator: Aase, S.; Conner, C.; Landsberger, S.; Vandegrift, G. F.; Wu, D. & Wygmans, D. G.
Object Type: Article
System: The UNT Digital Library
Study of electron and neutrino interactions (open access)

Study of electron and neutrino interactions

This is the final report for the DOE-sponsored experimental particle physics program at Virginia Tech to study the properties of the Standard Model of strong and electroweak interactions. This contract (DE-AS05-80ER10713) covers the period from August 1, 1980 to January 31, 1993. Task B of this contract, headed by Professor Alexander Abashian, is described in this final report. This program has been pursued on many fronts by the researchers-in a search for axions at SLAC, in electron-positron collisions in the AMY experiment at the TRISTAN collider in Japan, in measurements of muon decay properties in the MEGA and RHO experiments at the LAMPF accelerator, in a detailed analysis of scattering effects in the purported observation of a 17 keV neutrino at Oxford, in a search for a disoriented chiral condensate with the MiniMax experiment at Fermilab, and in an R&D program on resistive plate counters that could find use in low-cost high-quality charged particle detection at low rates.
Date: March 18, 1997
Creator: Abashian, A.
Object Type: Report
System: The UNT Digital Library
Study of electron and neutrino interactions. Final report (open access)

Study of electron and neutrino interactions. Final report

This is the final report for the DOE-sponsored experimental particle physics program at Virginia Tech to study the properties of the Standard Model of strong and electroweak interactions. This contract (DE-AS05-80ER10713) covers the period from August 1, 1980 to January 31, 1993. Task B of this contract, headed by Professor Alexander Abashian, is described in this final report. This program has been pursued on many fronts by the researchers in a search for axions at SLAC, in electron-positron collisions in the AMY experiment at the TRISTAN collider in Japan, in measurements of muon decay properties in the MEGA and RHO experiments at the LAMPF accelerator, in a detailed analysis of scattering effects in the purported observation of a 17 keV neutrino at Oxford, in a search for a disoriented chiral condensate with the MiniMax experiment at Fermilab, and in an R&D program on resistive plate counters that could find use in low-cost high-quality charged particle detection at low rates.
Date: March 18, 1997
Creator: Abashian, A.
Object Type: Report
System: The UNT Digital Library
Algorithms and design for a second-order automatic differentiation module (open access)

Algorithms and design for a second-order automatic differentiation module

This article describes approaches to computing second-order derivatives with automatic differentiation (AD) based on the forward mode and the propagation of univariate Taylor series. Performance results are given that show the speedup possible with these techniques relative to existing approaches. The authors also describe a new source transformation AD module for computing second-order derivatives of C and Fortran codes and the underlying infrastructure used to create a language-independent translation tool.
Date: July 1, 1997
Creator: Abate, J.; Bischof, C.; Roh, L. & Carle, A.
Object Type: Article
System: The UNT Digital Library
Higgs-photon associated production at hadron colliders (open access)

Higgs-photon associated production at hadron colliders

The authors present cross sections for the reactions p{anti p} {yields} H{gamma} and pp {yields} H{gamma} arising from the subprocess q{anti q} {yields} H{gamma}. The calculation includes the complete one-loop contribution from all light quarks and is the main source of Higgs-photon associated production in hadron colliders. At Tevatron energies, the cross section is typically 0.1 fb or less, while at LHC energies it can exceed 1.0fb.
Date: November 1, 1997
Creator: Abbasabadi, A.; Bowser-Chao, D.; Dicus, D.A. & Repko, W.W.
Object Type: Report
System: The UNT Digital Library
Development of regenerable copper-based sorbents for hot gas cleanup: Final technical report, September 1, 1995--August 31, 1996 (open access)

Development of regenerable copper-based sorbents for hot gas cleanup: Final technical report, September 1, 1995--August 31, 1996

The overall objective of this study was to determine the effectiveness of the copper-chromite sorbent (developed in previous ICCI-funded projects) for longer duration application under optimum conditions in the temperature range of 550{degrees}-650{degrees}C to minimize sorbent reduction and degradation during the cyclic process. Three (3) formulations of attrition resistant granules of the copper chromite sorbent (i.e., CuCr-10, CuCr-21, and CuCr-29) as well as one (1) copper chromite sorbent in pellet form (i.e., CuCr-36) were selected for cyclic desulfurization tests. The desulfurization and regeneration capabilities of the selected formulations as well as the effects of operating parameters were determined, to identify the {open_quotes}best{close_quotes} sorbent formulation and the optimum operating conditions. The durability of the {open_quotes}best{close_quotes} sorbent formulation was determined in {open_quotes}long-term{close_quotes} multicycle tests conducted at the optimum operating conditions. The attrition resistance of the selected formulations were determined and compared with those of other sorbents, including a limestone, a dolomite, and a commercial zinc titanate sorbent. The results obtained in this study indicate that, the CuCr-29 sorbent has excellent attrition resistance and desulfurization performance, which are far superior to the commercial zinc titanate sorbents. The optimum desulfurization temperature in terms of sorbent efficiency and utilization appears to be about 600{degrees}C. Sorbent …
Date: May 1, 1997
Creator: Abbasian, Javad; Slimane, Rachid B. & Wangerow, James R.
Object Type: Report
System: The UNT Digital Library
Design considerations for the development of a space qualification Short Wavelength Imaging Fourier Transform Spectrometer (SWIFTS) (open access)

Design considerations for the development of a space qualification Short Wavelength Imaging Fourier Transform Spectrometer (SWIFTS)

This document is the final report on work performed at Sandia National Laboratories during FY 1992 and 1993 for a Laboratory Directed Research and Development (LDRD) program to look at problems associated with the design and long term operation of a short wavelength imaging Fourier Transform (FT) spectrometer for use in space. In attempts to answer two fundamental questions: is a FT spectrometer with a resolution of 1 cm{sup {minus}1} covering the silicon detector wavelength range of 0.4 to 1.1 microns feasible in a long life space instrument and, if so, is it the best method of obtaining the desired information? Emphasis has been on identifying methods which minimize reliance on precision mechanical alignment and precise velocity control. An important consideration has also been to develop methods which will be compatible with a variety of self-scanning solid state imaging devices. A breadboard instrument was constructed using cube corner retroreflectors and a laser diode position reference. Some preliminary results are reported. This work is primarily intended to act as an aid to engineers at Sandia who wish to pursue the fabrication of a flight qualified instrument. The theoretical parts are intended to be somewhat tutorial in nature to aid the engineer …
Date: June 1, 1997
Creator: Abbink, R. E.
Object Type: Report
System: The UNT Digital Library
The azimuthal decorrelation of jets widely separated in rapidity (open access)

The azimuthal decorrelation of jets widely separated in rapidity

We study the azimuthal decorrelation between jets with pseudorapidity separation up to six units. The data were accumulated using the D0 detector during the 1994-1995 collider run of the Fermilab Tevatron at {radical}s = 1.8 TeV. The data are compared to two parton shower Monte Carlos (HERWIG and PYTHIA) and an analytical prediction using the leading logarithmic BFKL resummation. The final state jets as predicted by the parton showering Monte Carlos describe the data over the entire pseudorapidity range studied. The prediction based on the leading logarithmic BFKL resummation shows more decorrelation than the data as the rapidity interval increases.
Date: November 1, 1997
Creator: Abbott, B.
Object Type: Article
System: The UNT Digital Library
Color coherence in W + jet events (open access)

Color coherence in W + jet events

We report on preliminary studies of color coherence effects in p{anti p} collisions, based on data collected by the D0 detector during the 1994-1995 run of the Fermilab Tevatron collider, at a center of mass energy {radical}s = 1.8 TeV. Color interference effects are studied by examining particle distribution patterns in W + Jet events. The data are compared to Monte Carlo simulations with different color coherence implementations and to a recent analytic Modified-Leading-Log perturbative calculation based on the Local Parton-Hadron Duality hypothesis. Soft particle radiation is enhanced in the event plane relative to the transverse plane, in agreement with calculations in which the effects of color coherence are fully included.
Date: November 1, 1997
Creator: Abbott, B.
Object Type: Article
System: The UNT Digital Library
Determination of the b-quark production cross section in p{anti p} collisions at 630 GeV (open access)

Determination of the b-quark production cross section in p{anti p} collisions at 630 GeV

We present a preliminary measurement of the b-quark production cross section in p{anti p} collisions at {radical}s = 630 GeV. The analysis is based on 340 nb{sup -1} of data collected with the D0 detector at the Fermilab Tevatron Collider. We determine the ratio of the b-quark production cross sections at 630 GeV to 1800 GeV and compare our results with the CDF and UA1 measurements, and with the next-to- leading order QCD predictions.
Date: October 1, 1997
Creator: Abbott, B.
Object Type: Article
System: The UNT Digital Library
The dijet mass spectrum at D-Zero (open access)

The dijet mass spectrum at D-Zero

We present preliminary results from an analysis of jet data collected during the 1994-95 Tevatron Collider run with an integrated luminosity of 93 pb{sup -1}. Measurements of dijet mass spectra in {anti p}p collisions at {radical}s = 1.8 TeV are compared to next-to-leading order QCD calculations.
Date: November 1, 1997
Creator: Abbott, B.
Object Type: Article
System: The UNT Digital Library
A measurement of the ratio of production cross sections forW + 1 jet to W + 0 jets and comparisons to QCD (open access)

A measurement of the ratio of production cross sections forW + 1 jet to W + 0 jets and comparisons to QCD

A preliminary measurement of the ratio, R{sup 10}, of the production cross sections for W + 1 Jet and W + 0 Jets processes at {radical}s = 1800 GeV by the D0 Collaboration is presented. A comparison of this ratio is made to next-to-leading order calculations and the implications of these comparisons are discussed.
Date: November 1, 1997
Creator: Abbott, B.
Object Type: Article
System: The UNT Digital Library
Measurements of trilinear gauge boson couplings (open access)

Measurements of trilinear gauge boson couplings

Direct measurements of the trilinear gauge boson couplings by the D0 collaboration at Fermilab are reported. Limits on the anomalous couplings were obtained at a 95% CL from four diboson production processes: W{gamma} production with the W boson decaying to e{nu} or {mu}{nu}, WW production with both of the W bosons decaying to e{nu} or {mu}{nu}, WW/WZ production with one W boson decaying to e{nu} and the other W or Z boson decaying to two jets, and Z{gamma} production with the Z boson decaying to ee, {mu}{mu}, or {nu}{nu}. Limits were also obtained from a combined fit to W{gamma}, WW {yields} dileptons and WW/WZ {yields} e{nu}jj data samples.
Date: October 1, 1997
Creator: Abbott, B.
Object Type: Article
System: The UNT Digital Library
Photon and diphoton production, and k{sub T} Effects (open access)

Photon and diphoton production, and k{sub T} Effects

Isolated photon production at the D0 experiment is reviewed and recent results on di-photon production are presented.
Date: November 1, 1997
Creator: Abbott, B.
Object Type: Article
System: The UNT Digital Library
Search for heavy neutral gauge bosons at D-Zero (open access)

Search for heavy neutral gauge bosons at D-Zero

We report preliminary results of a search for a heavy neutral gauge boson, Z`, using the decay channel Z` {yields} ee . The data were collected with the D0 detector at the Fermilab Tevatron during the 1994-1995 p{anti p} collider run at {radical}s = 1.8 TeV and correspond to an integrated luminosity of {approx} 90 pb{sup -1}. Limits are set on the cross section times branching ratio for the process {anti p}p {yields} Z` {yields} ee as a function of the Z` mass. We exclude the existence of a heavy neutral gauge boson of mass less than 660 GeV/c{sup 2} (95% CL), assuming a Z` with the same coupling strengths to quarks and leptons as the standard model Z boson. Combining this analysis with DO`s 1992-1993 data set increases the limit to m{sub Z`} > 670 GeV/c{sup 2}.
Date: October 1, 1997
Creator: Abbott, B.
Object Type: Article
System: The UNT Digital Library
Search for high mass photon pairs in p{anti p}{yields}{gamma}{gamma}jj events at {radical}s = 1.8 TeV (open access)

Search for high mass photon pairs in p{anti p}{yields}{gamma}{gamma}jj events at {radical}s = 1.8 TeV

A search for new physics in the channel p{anti p} {yields} {gamma}{gamma}jj has been studied. In some extended Higgs models, a light neutral scalar Higgs boson is produced with suppressed couplings to fermions and standard model(SM) strength couplings to vector bosons(bosonic Higgs), thus enhancing the H {yields} {gamma}{gamma} channel. We required one photon in the event with E{sup {gamma}}{sub T} > 20 GeV, {vert_bar}{eta}{sup {gamma}}{vert_bar} < 1.1 or 1.5 < {vert_bar}{eta}{sup {gamma}}{vert_bar} < 2.0 and a second photon with E{sup {gamma}}{sub T} > 15 GeV, {vert_bar}{eta}{sup {gamma}}{vert_bar} < 1.1 or 1.5 < {vert_bar}{eta}{sup {gamma}}{vert_bar} < 2.25. Additionally, we required one hadronic jet in the event with E{sup jet}{sub T} > 20 GeV, {vert_bar}{eta}{sup jet}{vert_bar} < 2.0 and a second hadronic jet with E{sup jet}{sub T} > 15 GeV, {vert_bar}{eta}{sup jet}{vert_bar} < 2.25. The photons are required to have a {summation}{rvec E}{sub T}({gamma}) {>=} 10 GeV, and likewise the jets are required to have a {summation}{rvec E}{sub T}(jet) {>=} 10 GeV. The final M{sub {gamma}{gamma}} distribution is consistent with background and no resonance is observed. A 90(95)% C.L. upper limit cross section vs M{sub {gamma}{gamma}} is calculated, which ranges from 0.6(0.7) pb{sup -1} for M{sub {gamma}{gamma}} = 60 GeV/c{sup 2} to …
Date: October 1, 1997
Creator: Abbott, B.
Object Type: Article
System: The UNT Digital Library
Search for squarks and gluinos with the D-Zero Detector (open access)

Search for squarks and gluinos with the D-Zero Detector

We report on a search for squarks and gluinos in p{anti p} collisions at {radical} s= 1.8 TeV using the D0 detector at Fermilab. Data corresponding to 79.2 {+-} 4.2 pb{sup -1} were examined for events with large missing transverse energy, three or more jets, and the absence of isolated leptons. No events were observed significantly in excess of Standard Model background predictions, and we place limits on the Minimal Supergravity parameters M{sub 0} and M{sub 1/2}.
Date: October 1, 1997
Creator: Abbott, B.
Object Type: Article
System: The UNT Digital Library
Search for ZX {yields} {nu}{anti {nu}} b {anti b} Events in the D-Zero Detector (open access)

Search for ZX {yields} {nu}{anti {nu}} b {anti b} Events in the D-Zero Detector

We report on a search for a new particle, X, decaying via X {yields} b{anti b}, made through associated production with a Z boson. We use data collected with the D0 detector operating at the Fermilab Tevatron p{anti p} collider with {radical}s = 1.8 TeV. We utilize muon-tagged jets to identify b-quarks and the {nu}{anti {nu}} channel to detect Z bosons. Preliminary results on cross section limits for X masses between 90 GeV/c{sup 2} and 180 GeV/c{sup 2} are presented.
Date: October 1, 1997
Creator: Abbott, B.
Object Type: Article
System: The UNT Digital Library
Transverse momentum distributions of W and Z bosons produced in p {anti p} collisions at 1.8 TeV (open access)

Transverse momentum distributions of W and Z bosons produced in p {anti p} collisions at 1.8 TeV

The transverse momentum distributions of W and Z bosons produced in p{anti p} collisions at {radical}s = 1.8 TeV are measured with the D0 detector at Fermilab. The results are compared to QCD calculations which include soft gluon resummation. The transverse momentum distribution of the Z boson is consistent with the calculation of Ladinsky and Yuan, and is used to extract their non-perturbative parameter 92-
Date: October 1, 1997
Creator: Abbott, B.
Object Type: Article
System: The UNT Digital Library
D-Zero results on W boson properties (open access)

D-Zero results on W boson properties

The D0 experiment collected {approx} 15 pb{sup -1} in run 1A (1992- 1993) and {approx} 89 pb{sup -1} in run 1B (1994-1995) of the Fermilab Tevatron Collider using p{anti p} collisions at {radical}s = 1.8 TeV. Results from analyses of events with W and Z bosons are presented for the run 1B data samples. From W {yields} e{nu}, {mu}{nu} and Z {yields} ee, {mu}{mu} decays, the W and Z production cross sections and the W width are determined. Events with W {yields} {tau}{nu} decays are used to determine the ratio of the electroweak gauge coupling constants as a measure of lepton universality. Using W {yields} e{nu} and Z {yields} ee decays, the W boson mass is measured.
Date: October 1, 1997
Creator: Abbott, B.
Object Type: Article
System: The UNT Digital Library
Rapidity gaps and hard diffraction at the Tevatron (open access)

Rapidity gaps and hard diffraction at the Tevatron

Preliminary results on jet production with rapidity gaps in p{anti p} collisions are presented for both D0 and CDF. An excess of events with a forward rapidity gap is observed at both {radical}s=1800 GeV and 630 GeV, consistent with a hard single diffractive process. The first evidence for diffractive W production is presented. A class of events with two forward gaps and central dijets is observed at {radical}s=1800 GeV, a topology that is consistent with hard double pomeron exchange. Kinematic properties of events containing rapidity gaps are measured.
Date: June 1, 1997
Creator: Abbott, B. & Collaborations, CDF and D0
Object Type: Article
System: The UNT Digital Library
Probing color-singlet exchange at D0 (open access)

Probing color-singlet exchange at D0

We present latest preliminary results on hard color-singlet exchange in proton-antiproton collisions. The fraction of dijet events produced via color-singlet exchange is measured as a function of jet transverse energy, dijet pseudorapidity separation, and proton-antiproton center-of-mass energy. These results are qualitatively consistent with a color-singlet fraction that increases with increasing quark-initiated processes.
Date: July 1, 1997
Creator: Abbott, B.; Abolins, M.; Acharya, B. S. & Collaboration, D0
Object Type: Article
System: The UNT Digital Library