44 Matching Results

Search Results

Advanced search parameters have been applied.
in subjects: "66 Physics"  
Results: 1 - 24 next
open access

Non-universal SUSY breaking, hierarchy and squark degeneracty

Description: I discuss non-trivial effects in the soft SUSY breaking terms which appear when one integrates out heavy fields. The effects exist only when the SUSY breaking terms are non-universal. They may spoil (1) the hierarchy between the weak and high-energy scales, or (2) degeneracy among the squark masses even in the presense of a horizontal symmetry. I argue, in the end, that such new effects may be useful in probing physics at high-energy scales from TeV-scale experiments.
Date: March 15, 1995
Creator: Murayama, Hitoshi
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Gigagauss Magnetic Field Generation From High Intensity Laser Solid Interactions

Description: Intense laser (>10<sup>21</sup> W/cm2 ) sources using pulse compression techniques in the sub-picosecond time frame have been used to create dynamic electric field strenghs in excess of 100 Megavolts/micron with associated magnetic field strengths in the Gigagauss regime. We have begun a series of experiments using the Petawatt Laser system at LLNL to determine the potential of these sources for a variety of applications. Hot electron spectra from laser-target interactions in Au have been measu… more
Date: October 15, 1998
Creator: Cowan, T.; Moran, M.; Hammer, J.; Hatchett, S.; Hunt, A.; Key, M. H. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Differential geometry on Hopf algebras and quantum groups

Description: The differential geometry on a Hopf algebra is constructed, by using the basic axioms of Hopf algebras and noncommutative differential geometry. The space of generalized derivations on a Hopf algebra of functions is presented via the smash product, and used to define and discuss quantum Lie algebras and their properties. The Cartan calculus of the exterior derivative, Lie derivative, and inner derivation is found for both the universal and general differential calculi of an arbitrary Hopf algeb… more
Date: December 15, 1994
Creator: Watts, P.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
open access

Nuclear structure at intermediate energies. Progress report

Description: We report here oil the progress that we made for the nine months beginning October 1, 1991 for DOE Grant No. DE-FG05-87ER40309. The report covers the third year of a three year grant. Since we are submitting an accompanying Grant Renewal Proposal, we provide in this report more background information than usual for the different projects. The theme that unites the experiments undertaken by the Bonner Lab Medium Energy Group is a determination to understand in detail the many facets and manifest… more
Date: July 15, 1992
Creator: Bonner, B. E. & Mutchler, G. S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

FT-ICR mass spectrometry of very highly charged atomic ions

Description: The authors report FT-ICR measurements of samples trapped in the electron beam ion trap (EBIT) at Livermore. They made use of the access provided by the radial x-ray slots. They constructed two probes that could be inserted into the 2-mm wide slots. The probes each subtend only 25{degree} and face each other 180{degree} apart. They show a typical transformed spectrum of highly charged {sup 84}Kr ions obtained with this system. The spectrum was obtained by exciting with a 300-{mu}s sweep from 17… more
Date: May 15, 1995
Creator: Schweikhard, L.; Beck, B. & Beiersdorfer, P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

EUVE photometry of SS Cygni: Dwarf nova outbursts and oscillations

Description: The authors present EUVE Deep Survey photometry and AAVSO optical measurements of the 1993 August and 1994 June/July outbursts of the dwarf nova SS Cygni. The EUV and optical light curves are used to illustrate the different response of the accretion disk to outbursts which begin at the inner edge and propagate outward, and those which begin at the outer edge and propagate inward. Furthermore, the authors describe the properties of the quasi-coherent 7--9 s sinusoidal oscillations in the EUV fl… more
Date: May 15, 1995
Creator: Mauche, C.W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Recent results from the super EBIT

Description: The Super EBIT device at LLNL can produce and trap any highly charged ion at rest in the laboratory, including bare U{sup 92+} ions. Recently, the ionization cross sections for high-Z hydrogenlike ions have been measured for the first time, and measurements of the L-shell ionization cross sections for uranium ions are in progress. The two-electron contributions to the ground state energies of heliumlike ions have been directly measured using a novel technique, and spectra of 2s-2p transitions i… more
Date: September 15, 1995
Creator: Marrs, R.E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

A limit on {sigma} {center_dot} BR (B{sub c}{sup {+-}} {yields} J/{psi} + {pi}{sup {+-}})/{sigma} {center_dot} BR(B{sub u}{sup {+-}} {yields} J/{psi} + K{sup {+-}}) in {radical}s = 1.8 TeV proton-antiproton collisions

Description: We report on the results of a search for the B{sub c} (b{bar c}) meson in the decay B{sub c}{sup +-} {yields} J/{psi} + {pi}{sup +-}. This search is guided by a control sample of decays of B{sub u} mesons to J/{psi} + K and uses {approx_equal} 75pb{sup -1} of data collected at the Collider Detector Facility (CDF) at Fermilab. The lifetime of the B{sub c} meson is unknown, so the 95% confidence level limit on {sigma} {center_dot} BR(B{sub c} {yields} {psi} + {pi})/{sigma} {center_dot} BR(B{sub u… more
Date: July 15, 1995
Creator: Abe, F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Excitations of the Transversely Polarized Spin Density Waves in Chromium

Description: Inelastic neutron scattering measurements across the TSDW satellites of chromium were performed at {Delta}E=5,20meV, both under zero field and 5T magnetic field. Analysis concerning the transverse magnetic excitations (T{sub 1},T{sub 2}) and the longitudinal magnetic excitations (L) indicates that T{sub 1} and L are equally intense while T{sub 2} dominates and becomes more so at higher energies.
Date: July 15, 1997
Creator: Lee, W. T.; Werner, S. A.; Fernandez-Baca, J. A. & Fishman, R. S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Quantum mechanics from an equivalence principle

Description: The authors show that requiring diffeomorphic equivalence for one-dimensional stationary states implies that the reduced action S{sub 0} satisfies the quantum Hamilton-Jacobi equation with the Planck constant playing the role of a covariantizing parameter. The construction shows the existence of a fundamental initial condition which is strictly related to the Moebius symmetry of the Legendre transform and to its involutive character. The universal nature of the initial condition implies the Sch… more
Date: May 15, 1997
Creator: Faraggi, A. E. & Matone, M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Short range rapidity correlations from the Bose-Einstein effect and intermittency: A quantitative demonstration

Description: A measurement of the two-particle correlation of identified pions was performed in the E802/E859 magnetic spectrometer on the interval 1.5 {le} y {le} 2.0, {delta}{phi} = 0.4 rad, for central {sup 28}Si + Au collisions. It is demonstrated that the two-pion correlation in rapidity is entirely due to Bose-Einstein interference. The directly measured exponential correlation length is {zeta}{sub y} = 0.20 {+-} 0.03 for two {pi}{sup {minus}}, with strength R(0,0) {approximately} 1%, in agreement wit… more
Date: May 15, 1997
Creator: Tannenbaum, M.J. & Collaboration, E802 /E859
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Definition of neutron lifespan and neutron lifetime in MCNP4B

Description: MCNP4B was released in early 1997. In this new version, several major changes were made to the underlying theory used to estimate the non-adjoint-weighted removal, fission, capture, and escape prompt-neutron lifetimes. These four lifetimes are now being calculated in accordance to the neutron-balance theory described by Spriggs et al. in which the non-adjoint-weighted lifetime for a particular type of reaction (i.e., fission, capture, escape, removal, etc.) is defined as the total neutron popul… more
Date: January 15, 1997
Creator: Busch, R. D.; Spriggs, G. D. & Hendricks, J. S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Recent results from CDF

Description: We first present recent CDF results on the top quark, covering the measurement of the t{anti t} production cross section and the top quark mass, the observation of hadronic W decays in top events, the measurement of V{sub tb}, the search for flavor changing neutral current decays, and kinematical properties of t{anti t} production. Then we present one topic from CDF exotic physics results, i.e., the search for first-generation leptoquarks, and one topic from CDF B physics results, i.e., the mea… more
Date: February 15, 1998
Creator: Takikawa, K. & CDF
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Anomalies

Description: I discuss the role of anomalies in the modern development of quantum field theory and their implications for physics.
Date: February 15, 1999
Creator: Bardeen, William A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Neutron total and capture cross section measurements and resonance parameter analysis of tungsten from 0.01 eV to 200 eV

Description: Natural tungsten metal was measured using neutron time-of-flight spectroscopy at the Rensselaer Polytechnic Institute (RPI) Gaerttner Laboratory linear accelerator to determine the tungsten resonance parameters. Three separate measurements were performed: transmission, capture, and self-indication. Previous measurements did not employ all three experiment types and used less sophisticated methods. The current work improves on the published tungsten data base and reduces resonance parameter unce… more
Date: June 15, 1998
Creator: Werner, C. J.; Block, R. C.; Slovacek, R. E.; Overberg, M. E.; Moretti, B. E.; Burke, J. A. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Quantum chromodynamics and nuclear physics at extreme energy density. Progress report, May 15, 1994--May 14, 1995

Description: A brief summary of the progress made for the year is given for each of the following areas: (1) quark-gluon plasma and relativistic heavy ion collisions (nine contributions); (2) effective theories for hadrons and nuclei (four contributions); (4) renormalization group approach to field theory at finite temperature; (5) symmetry-preserving regularization; and (6) an effective field theory approach to the cosmological constant problem.
Date: May 15, 1995
Creator: Mueller, B. & Springer, R.P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Stable superstring relics

Description: The authors investigate the cosmological constraints on exotic stable matter states which arise in realistic free fermionic superstring models. These states appear in the superstring models due to a ``Wilson-line`` breaking of the unifying non-Abelian gauge symmetry. In the models that they consider the unifying SO(10) gauge symmetry is broken at the string level to SO(6) x SO(4), SU(5) x U(1) or SU(3) x SU(2) x U(1). The exotic matter states are classified according to the patterns of the SO(1… more
Date: May 15, 1996
Creator: Chang, S.; Coriano, C. & Faraggi, A.E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

On the road to the solution of the Solar Neutrino Problem

Description: The present status of solar neutrino experiments is reviewed. The discrepancy between the experimental results and the theoretical expectations has come to be known as the Solar Neutrino Problem. Possible solutions to this problem are discussed. The next generation of solar neutrino experiments are described.
Date: August 15, 1995
Creator: Norman, E.B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Quantum chromodynamics and nuclear physics at extreme energy density. Progress report, May 15, 1993--May 14, 1994

Description: This report briefly discusses the following topics: quark-gluon plasma and high-energy collisions; hadron structure and chiral dynamics; nonperturbative studies and nonabelian gauge theories; and studies in quantum field theory.
Date: May 15, 1994
Creator: Mueller, B. & Springer, R.P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

The Measurement of xi'/xi at Fermilab KTeV-E832

Description: The status of the analysis effort for the 25% data sample taken during the Fermilab '96-'97 fixed target run for {epsilon}'/{epsilon} measurement from KTeV is presented here. Detector performance, data statistics, background subtractions, data and monte-carlo comparison for acceptance corrections, as well as the preliminary results on K{sub L}{yields}{pi}{sup 0}{gamma}{gamma} are described in more detail. Prospects for KTeV 99, in the up coming 6 months '99 fixed target run, are also discussed … more
Date: February 15, 1999
Creator: Hsiung, Yee Bob
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

A spectroscopic study of hydrogen atom and molecule collisions. Progress report, 1994--1997

Description: In this project the fundamental processes which occur in low energy collisions of excited states of atomic hydrogen with other atoms and ions are being studied with optical, vacuum ultraviolet and laser spectroscopy. This report covers the period from 1994 to early 1997. We begin here with a brief description of the status of the work at the beginning of this project period, then discuss the goals for this period, our results, and the work in progress now. As the accompanying renewal proposal d… more
Date: January 15, 1997
Creator: Kielkopf, J.F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Electron-atom collision studies using optically state-selected beams. Final report, May 15, 1991--May 14, 1994

Description: As stated in the original proposal, the goal of the project has been to perform electron-scattering experiments on a few model systems with emphasis on resolving all the quantum-state variables possible. The purpose of these experimental studies has been to provide a set of measurements of unprecedented accuracy and completeness that can be used as benchmarks for comparison with theoretical calculations. During the period covered by this report, the work has concentrated on measuring low-energy… more
Date: March 15, 1998
Creator: Kelley, Michael H. & McClelland, Jabez J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Isolated prompt photon production

Description: We show that the conventionally defined partonic cross section for the production of isolated prompt photons is not an infrared safe quantity. We work out the case of e{sup +}e{sup -} {yields} {gamma} + X in detail, and we discuss implications for hadron reactions such as p{bar p} {yields} {gamma} + X.
Date: August 15, 1997
Creator: Berger, E. L.; Guo, Xiaofeng & Qiu, Jianwei
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Vortex structure in rotating Rayleigh-Benard convection

Description: The authors investigate the flow patterns in a cylindrical rotating Rayleigh-Benard convection cell with radius-to-height ratio {Gamma} = 0.5. The Rayleigh number R is 2 x 10{sup 8}, the dimensionless rotation rate {Omega} varies from 10{sup 4} to 5 x 10{sup 4}, and the convective Rossby number Ro is between 2 and 0.4. Measurements of the velocity field in the volume adjacent to the top of the cell are acquired with a scanning particle image velocimetry (PIV) system. The authors present quantit… more
Date: July 15, 1997
Creator: Vorobieff, P. & Ecke, R.E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
Back to Top of Screen