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Using anti pp annihilation to find exotic mesons

Description: Present data suggests that a number of mesons have been found which cannot be accommodated in standard anti qq multiplets. Theory suggests that such exotic mesons should exist in the spectrum of Quantum Chromodynamics, but provides little guide to their properties. It is argued that a high luminosity, low energy anti pp machine would be a powerful tool with which to search for such exotics.
Date: October 1, 1987
Creator: Sharpe, S.R.
Partner: UNT Libraries Government Documents Department

Staggering towards a calculation of weak amplitudes

Description: An explanation is given of the methods required to calculate hadronic matrix elements of the weak Hamiltonians using lattice QCD with staggered fermions. New results are presented for the 1-loop perturbative mixing of the weak interaction operators. New numerical techniques designed for staggered fermions are described. A preliminary result for the kaon B parameter is presented. 24 refs., 3 figs.
Date: September 1, 1988
Creator: Sharpe, S.R.
Partner: UNT Libraries Government Documents Department

Kaon decay amplitudes using staggered fermions

Description: A status report is given of an attempt, using staggered fermions to calculate the real and imaginary parts of the amplitudes for K ..-->.. ..pi pi..,. Semi-quantitative results are found for the imaginary parts, and these suggest that epsilon' might be smaller than previously expected in the standard model.
Date: December 1, 1986
Creator: Sharpe, S.R.
Partner: UNT Libraries Government Documents Department

Site selection report basalt waste isolation program near-surface test facility

Description: A site selection committee was established to review the information gathered on potential sites and to select a site for the Near-Surface Test Facility Phase I. A decision was made to use a site on the north face of Gable Mountain located on the Hanford Site. This site provided convenient access to the Pomona Basalt Flow. This flow was selected for use at this site because it exhibited the characteristics established in the primary criteria. These criteria were: the flows thickness; its dryness; its nearness to the surface; and, its similarities to basalt units which are candidates for the repository. After the selection of the Near-Surface Test Facility Phase I Site, the need arose for an additional facility to demonstrate safe handling, storage techniques, and the physical effects of radioactive materials on an in situ basalt formation. The committee reviewed the sites selected for Phase I and chose the same site for locating Phase II of the Near-Surface Test Facility.
Date: December 4, 1978
Creator: Sharpe, S.D.
Partner: UNT Libraries Government Documents Department

Status of lattice field theory calculations

Description: This report briefly discusses the following topics: overview of all present calculation; reliability criteria for quenched calculation; quenched versus full QCD, and difficulties facing full QCD; results for the quenched pion wavefunction''; results for the quenched hadron spectrum; results for quenched B{sub K}; A new method for calculating the surface tension; the non-pertubative upper bound on the Higgs mass; and toward the TERAFLOP machine.
Date: January 1, 1990
Creator: Sharpe, S.R.
Partner: UNT Libraries Government Documents Department

Problems with the quenched approximation in the chiral limit

Description: In the quenched approximation, loops of the light singlet meson (the [eta][prime]) give rise to a type of chiral logarithm absent in full QCD. These logarithms are singular in the chiral limit, throwing doubt upon the utility of the quenched approximation. In previous work, I summed a class of diagrams, leading to non-analytic power dependencies such as [l angle][anti [psi]][psi][r angle] [proportional to] m[sub q][sup [minus][delta]]/(1+[delta]) I suggested, however, that these peculiar results could be redefined away. Here I give an alternative derivation of the results, based on the renormalization group, and argue that they cannot be redefined away. I discuss the evidence (or lack thereof) for such effects in numerical data.
Date: January 1, 1992
Creator: Sharpe, S.R.
Partner: UNT Libraries Government Documents Department

Recent progress in lattice QCD

Description: A brief overview of the status of lattice QCD is given, with emphasis on topics relevant to phenomenology. The calculation of the light quark spectrum, the lattice prediction of [alpha] [sub [ovr MS]] (M [sub Z]), and the calculation of f[sub B] are discussed. 3 figs., 3 tabs., 40 refs.
Date: December 1, 1992
Creator: Sharpe, S.R.
Partner: UNT Libraries Government Documents Department

Problems with the quenched approximation in the chiral limit

Description: In the quenched approximation, loops of the light singlet meson (the {eta}{prime}) give rise to a type of chiral logarithm absent in full QCD. These logarithms are singular in the chiral limit, throwing doubt upon the utility of the quenched approximation. In previous work, I summed a class of diagrams, leading to non-analytic power dependencies such as {l_angle}{anti {psi}}{psi}{r_angle} {proportional_to} m{sub q}{sup {minus}{delta}}/(1+{delta}) I suggested, however, that these peculiar results could be redefined away. Here I give an alternative derivation of the results, based on the renormalization group, and argue that they cannot be redefined away. I discuss the evidence (or lack thereof) for such effects in numerical data.
Date: December 31, 1992
Creator: Sharpe, S. R.
Partner: UNT Libraries Government Documents Department

Recent progress in lattice QCD

Description: A brief overview of the status of lattice QCD is given, with emphasis on topics relevant to phenomenology. The calculation of the light quark spectrum, the lattice prediction of {alpha} {sub {ovr MS}} (M {sub Z}), and the calculation of f{sub B} are discussed. 3 figs., 3 tabs., 40 refs.
Date: December 1, 1992
Creator: Sharpe, S. R.
Partner: UNT Libraries Government Documents Department

Non-Perturbative Renormalization Constants Using Ward Identities

Description: The authors extend the application of vector and axial Ward identities to calculate b{sub A}, b{sub P} and b{sub T}, coefficients that give the mass dependence of the renormalization constants of the corresponding bilinear operators in the quenched theory. The extension relies on using operators with non-degenerate quark masses. It allows a complete determination of the O(a) improvement coefficients for bilinears in the quenched approximation using Ward Identities alone. Only the scale dependent normalization constants Z{sub P}{sup 0} (or Z{sub S}{sup 0}) and Z{sub T} are undetermined. The authors present results of a pilot numerical study using hadronic correlators.
Date: July 14, 1998
Creator: Bhattacharya, T.; Chandrasekharan, S.; Gupta, R.; Lee, W. & Sharpe, S.
Partner: UNT Libraries Government Documents Department

General Motors Corporation and Pacific Northwest Laboratory Staff Exchange: Instrumentation for rapid measurement of automotive exhaust emissions

Description: Information in this report on the staff exchange of Pacific Northwest Laboratory (PNL) staff with the AIGER Consortium (General Motors, Ford, Chrysler, Navistar, the environmental protection Agency, and the California Air Resources Board) includes the purpose and objectives, a summary of activities, significant accomplishments, significant problems, industry benefits realized, recommended follow-on work and potential benefits from that work, and two appendices. Appendix A is a brief description of the fast gas chromatography and infrared spectroscopy chemometric technologies and their application to the rapid characterization of automobile exhaust emissions. Appendix B is a list of key contacts and the schedule of activities pertaining to the staff exchange.
Date: July 1, 1995
Creator: Griffin, J.W.; Sharpe, S.W. & Sloane, T.M.
Partner: UNT Libraries Government Documents Department

Pacific Northwest Laboratory CALIOPE overview

Description: This overview covers progress in the following areas in which Pacific Northwest Laboratory contributes to the CALIOPE Program: (1) Fabrication of electro-optic modulators to generate FM-coding on IR lasers in the 8-12 and 3-5 {mu}m regions. (2) IR spectroscopy of signature species, abnormal isotopic distributions, hydrolysis and kinetics of effluents interacting with the atmosphere, and reflectance measurements of natural surfaces. (3) Systems analysis of FM-DIAL concepts, including lateral phase coherence and MTF measurements, and laboratory tests of detector technology and demodulation methods. (4) Field tests of FM-DIAL, covering field validation of portable diode laser concepts, FM-CO{sub 2} interrogation of Hanford sites, and signal returns from natural specular surfaces. (5) Ancillary matters: ground-truthing at Hanford (and RSTR?), countermeasures, and new laser design concepts.
Date: March 1, 1995
Creator: McDowell, R.S.; Kelly, J.F. & Sharpe, S.W.
Partner: UNT Libraries Government Documents Department

Scaling behavior of improvement and renormalization constants.

Description: This talk summarizes results for all the scale independent renormalization constants for bilinear currents ( Z A, ZV, and Zs/Zp), the improvement constants (CA, CV, and CT), the quark mass dependence of 20, and the coefficients of the equation of motion operators for O(a) improved lattice QCD. Using data at p = 6.0, 6.2 and 6.4 we study the scaling behavior of these quantities and quantify residual discretization errors.
Date: January 1, 2001
Creator: Bhattacharya, T. (Tanmoy); Gupta, R. (Rajan); Lee, W. (Weonjong) & Sharpe, S. R. (Stephen R.)
Partner: UNT Libraries Government Documents Department

Nonperturbative estimates of the Standard Model parameters

Description: This is the final report of a three-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The project objectives were (1) to develop highly optimized codes for the simulation of lattice Quantum Chromodynamics (QCD) on the Connection Machine CM-5, (2) to use these codes to carry out a comprehensive analysis of Standard Model phenomenology using a large statistical sample, and (3) to combine the results of numerical simulations with experimental data to estimate the unknown parameters of the Standard Model. We were successful in achieving all these goals. Our highly optimized codes were used to debug both the hardware and software of the CM-5. We carried out a comprehensive study of the hadron spectrum, decay constants for mesons, semi- leptonic form factors, form-factors for the rare decay B {r_arrow} K{sup *} {gamma}, {pi}-{pi} scattering amplitude, and matrix elements of a variety of 4-fermion weak operators. From these observables we were able to predict the masses of light quarks, m{sub u} + m{sub d} and m{sub s}, matrix elements of the Cabibbo-Kobayashi-Maskawa mixing matrix, and the CP violating parameters {epsilon} and {epsilon}{prime}. Our new estimates of light-quark masses are roughly half of commonly believed values, and we predict a much larger value for {epsilon}{prime}/{epsilon}, which will be tested experimentally over the next few years. 15 refs.
Date: August 1, 1997
Creator: Gupta, R.; Bhattacharya, T.; Tamayo, P.; Grandy, T.; Kilcup, G. & Sharpe, S.
Partner: UNT Libraries Government Documents Department

Weak matrix elements for CP violation.

Description: We present preliminary results of matrix elements of four fermion operators relevant to the determination of e and E ' / E using staggered fermions. To calculate the matrix elements relevant to CP violation in Kaon decays it is important to use a lattice formulation which preserves (some) chiral symmetry.
Date: January 1, 2001
Creator: Lee, W. (Weonjong); Gupta, R. (Rajan); Christ, N.; Fleming, G. T.; Kilcup, G. (Gregory); Liu, G. et al.
Partner: UNT Libraries Government Documents Department

Multi-watt 589nm fiber laser source

Description: We have demonstrated 3.5W of 589nm light from a fiber laser using periodically poled stoichiometric Lithium Tantalate (PPSLT) as the frequency conversion crystal. The system employs 938nm and 1583nm fiber lasers, which were sum-frequency mixed in PPSLT to generate 589nm light. The 938nm fiber laser consists of a single frequency diode laser master oscillator (200mW), which was amplified in two stages to >15W using cladding pumped Nd{sup 3+} fiber amplifiers. The fiber amplifiers operate at 938nm and minimize amplified spontaneous emission at 1088nm by employing a specialty fiber design, which maximizes the core size relative to the cladding diameter. This design allows the 3-level laser system to operate at high inversion, thus making it competitive with the competing 1088nm 4-level laser transition. At 15W, the 938nm laser has an M{sup 2} of 1.1 and good polarization (correctable with a quarter and half wave plate to >15:1). The 1583nm fiber laser consists of a Koheras 1583nm fiber DFB laser that is pre-amplified to 100mW, phase modulated and then amplified to 14W in a commercial IPG fiber amplifier. As a part of our research efforts we are also investigating pulsed laser formats and power scaling of the 589nm system. We will discuss the fiber laser design and operation as well as our results in power scaling at 589nm.
Date: January 19, 2006
Creator: Dawson, J. W.; Drobshoff, A. D.; Beach, R. J.; Messerly, M. J.; Payne, S. A.; Brown A. et al.
Partner: UNT Libraries Government Documents Department

The climatic and hydrologic history of southern Nevada during the late Quaternary

Description: Understanding climate change during the expected life span of a potential high-level nuclear-waste repository at Yucca Mountain, Nevada, requires estimates of future climate boundary conditions. These climate boundary conditions are governed by changes in the Earth's orbital properties (eccentricity, obliquity, precession) that determine insolation. Subcycles of the 400,000 year insolation-controlled climate cycles last approximately 100,000 years. This report describes the changes which have occurred in the climatic history of Southern Nevada during the past 400,000 years. These changes provide a basis for understanding the changes which may occur during the long-term future in this area.
Date: September 21, 1999
Creator: Forester, R.M.; Bradbury, J.P.; Carter, C.; Elvidge-Tuma, A.B.; Hemphill, M.L.; Lundstrom, S.C. et al.
Partner: UNT Libraries Government Documents Department