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Using field theory in hadron physics

Description: Topics are covered on the connection of field theory and hadron physics. The renormalization group and infrared and ultraviolet limits of field theory, in particular quantum chromodynamics, spontaneous mass generation, color confinement, instantons, and the vacuum state in quantum chromodynamics are treated. 21 references. (JFP)
Date: March 1, 1978
Creator: Abarbanel, H.D.I.
Partner: UNT Libraries Government Documents Department

Thermodynamics of higher dimensional black holes

Description: We discuss the thermodynamics of higher dimensional black holes with particular emphasis on a new class of spinning black holes which, due to the increased number of Casimir invariants, have additional spin degrees of freedom. In suitable limits, analytic solutions in arbitrary dimensions are presented for their temperature, entropy, and specific heat. In 5 + 1 and 9 + 1 dimensions, more general forms for these quantities are given. It is shown that the specific heat for a higher dimensional black hole is negative definite if it has only one non-zero spin parameter, regardless of the value of this parameter. We also consider equilibrium configurations with both massless particles and massive string modes. 16 refs., 3 figs.
Date: May 1, 1986
Creator: Accetta, F.S. & Gleiser, M.
Partner: UNT Libraries Government Documents Department

Two aspects of one loop structure: Unitarity delay in the Standard Model and modular invariance in string theory

Description: We study two aspects of one loop structures in quantum field theories which describe two different areas of particle physics: the one loop unitarity behavior of the Standard Model of electroweak interactions and modular invariance of string model theory. Loop expansion has its importance in that it contains quantum fluctuations due to all physical states in the theory. Therefore, by studying the various models to one loop, we can understand how the contents of the theory can contribute to physically measurable quantities and how the consistency at quantum level restricts the physical states of the theory, as well. In the first half of the thesis, we study one loop corrections to the process {ital e}{sup +}{ital e}{sup {minus}} {yields} {ital W}{sup +}{ital W}{sup {minus}}. In this process, there is a delicate unitarity-saving cancellation between s-channel and t-channel tree level Feynman diagrams. If the one loop contribution due to heavy particles corrects the channels asymmetrically, the cancellation, hence unitarity, will be delayed up to the mass scale of these heavy particles. We refer to this phenomena as the unitarity delay effect. Due to this effect, cross section below these mass scales can have significant radiative corrections which may provide an appropriate window through which we can see the high energy structure of the Standard Model from relatively low energy experiments. In the second half, we will show how quantum consistency can restrict the physical states in string theory. 53 refs., 13 figs.
Date: August 1, 1989
Creator: Ahn, C.
Partner: UNT Libraries Government Documents Department

Diproton resonances in the mass region 2100 to 2800 MeV. [Dispersion relations, scattering amplitude]

Description: A striking energy dependence was observed in the difference between the p--p total cross sections for parallel and antiparallel longitudinal spin states, ..delta..sigma/sub L/ = sigma/sup Tot/(reverse ..-->..)-sigma/sup Tot/(double ..-->..). The structure appears around P/sub lab/ = 1.5 GeV/c where ..delta..sigma/sub L/ = -16.7 mb and is seen in sigma/sup Tot/(double ..-->..) rather than sigma/sup Tot/(reverse ..-->..). The experiments were performed at Argonne National Laboratory using a standard transmission technique. From the dispersion analysis of a forward p--p scattering amplitude using the data on ..delta..sigma/sub L/, Grein and Kroll have shown that the Argand plot of the amplitude has a clear resonance-like behavior around proton-incident momentum of 1.5 GeV/c. At the same energy range, the p--p polarization at fixed -+ also shows a remarkable energy dependence. In addition, a prominent energy dependence was observed for C/sub LL/, the spin correlation parameter for elastic pp scattering with beam and target both longitudinally polarized. The possibility of a resonance was further pursued by studying Legendre expansion coefficients of p--p differential cross section and polarization data. The analysis showed a partial wave, /sup 3/F/sub 3/ consistent with having a resonant behavior. Based on a phase-shift analysis, Hoshizaki also showed that /sup 3/F/sub 3/ seems to resonate. This resonant state would have the quantum number J/sup P/ = 3/sup -/, mass approx. 2260 MeV, width approx. 200 MeV and elasticity 20 to 30%. This exotic state may be described by the MIT bag model. Also speculated are several more diproton resonances in the mass region 2100 to 2800 MeV. 37 references.
Date: January 1, 1978
Creator: Akihiko, Y.
Partner: UNT Libraries Government Documents Department

Scalar and vector contributions to p p yields. Lambda. Lambda

Description: A quark model which includes both scalar and vector contributions to the reaction {bar p}p {yields} {bar {Lambda}}{Lambda} is presented. DWBA calculations of differential cross sections, polarizations and spin correlation coefficients are compared to experimental results at several energies. The results are sensitive to details of the reaction mechanism and to the parameters of the {bar {Lambda}}{Lambda} interaction. 10 refs., 5 figs.
Date: January 1, 1990
Creator: Alberg, M.A. (Seattle Univ., WA (USA). Dept. of Physics Washington Univ., Seattle, WA (USA). Dept. of Physics); Henley, E.M.; Wilets, L. (Washington Univ., Seattle, WA (USA). Dept. of Physics) & Kunz, P.D. (Colorado Univ., Boulder, CO (USA). Nuclear Physics Lab.)
Partner: UNT Libraries Government Documents Department

Cosmology for high energy physicists

Description: The standard big bang model of cosmology is presented. Although not perfect, its many successes make it a good starting point for most discussions of cosmology. Places are indicated where well understood laboratory physics is incorporated into the big bang, leading to successful predictions. Much less established aspects of high energy physics and some of the new ideas they have introduced into the field of cosmology are discussed, such as string theory, inflation and monopoles. 49 refs., 5 figs.
Date: November 1, 1987
Creator: Albrecht, A.
Partner: UNT Libraries Government Documents Department

Small scale structure on cosmic strings

Description: I discuss our current understanding of cosmic string evolution, and focus on the question of small scale structure on strings, where most of the disagreements lie. I present a physical picture designed to put the role of the small scale structure into more intuitive terms. In this picture one can see how the small scale structure can feed back in a major way on the overall scaling solution. I also argue that it is easy for small scale numerical errors to feed back in just such a way. The intuitive discussion presented here may form the basis for an analytic treatment of the small structure, which I argue in any case would be extremely valuable in filling the gaps in our resent understanding of cosmic string evolution. 24 refs., 8 figs.
Date: October 30, 1989
Creator: Albrecht, A.
Partner: UNT Libraries Government Documents Department

Evolution of cosmic string networks

Description: We summarize our new results on cosmic strings. These results include: the application of non-equilibrium statistical mechanics to cosmic string evolution, a simple ''one scale'' model for the long strings which has a great deal of predictive power, results from large scale numerical simulations, and a discussion of the observational consequences of our results. An upper bond on G/mu/ of approximately 10/sup /minus/7/ emerges from the millisecond pulsar gravity wave bound. We discuss how numerical uncertainties affect this. Any changes which weaken the bound would probably also give the long strings the dominant role in producing observational consequences. 22 refs.
Date: June 1, 1989
Creator: Albrecht, A. & Turok, N.
Partner: UNT Libraries Government Documents Department

Searching for quark and lepton compositeness at the SSC

Description: We examine a variety of issues connected with searching for compositeness at the SSC. These include effects of resolution, alternative methods of looking for deviations from QCD predictions, advantages of polarized beams, and effects of compositeness on photon detection. We also consider how physics may look if the compositeness scale is as low as a few TeV. 17 refs.
Date: January 1, 1984
Creator: Albright, C. H.; Bars, I.; Blumenfeld, B.; Braune, K.; Dine, M.; Ferbel, T. et al.
Partner: UNT Libraries Government Documents Department

Heavy leptons at the SSC

Description: It is argued that detection of heavy leptons at the Superconducting Super Collider seems to be very difficult but perhaps not impossible. The feasibility is shown to depend critically upon the ability to identify events with W's decaying hadronically and missing transverse momentum. (LEW)
Date: December 15, 1987
Creator: Anderson, G. & Hinchliffe, I.
Partner: UNT Libraries Government Documents Department

Evidence for quarks and gluons

Description: The evidence from the experiments of deep inelastic electron and muon scattering and of ..mu.. pair production at high energy that the neutron and proton are made of quarks and gluons is given.
Date: April 1, 1980
Creator: Anderson, H.L.
Partner: UNT Libraries Government Documents Department

Color transparency study group

Description: The group studied the relatively new notion of color transparency, discussed present experimental evidence for the effect, and explored several ideas for future experiments. This write-up summarizes these discussions. 11 refs., 1 fig.
Date: January 1, 1990
Creator: Appel, J.A.; Pordes, S. (Fermi National Accelerator Lab., Batavia, IL (USA)); Botts, J. (Washington Univ., Seattle, WA (USA)); Bunce, G. (Brookhaven National Lab., Upton, NY (USA)) & Farrar, G. (Rutgers--the State Univ., New Brunswick, NJ (USA))
Partner: UNT Libraries Government Documents Department

Large momentum transfer electron scattering from few-nucleon systems

Description: A review is given of the experimental results from a series of measurements at SLAC of large momentum transfer (Q/sup 2/ > 20 fm/sup -2/) electron scattering at forward angles from nuclei with A less than or equal to 4. Theoretical interpretations of these data in terms of traditional nuclear physics models and in terms of quark constituent models are described. Some physics questions for future experiments are explored, and a preview of possible future measurements of magnetic structure functions of light nuclei at large Q/sup 2/ is given.
Date: August 1, 1979
Creator: Arnold, R.G.
Partner: UNT Libraries Government Documents Department

Detecting heavy flavors at CBA

Description: In the CBA luminosity range (L approx. = 10/sup 32/-10/sup 33/cm/sup -2/sec/sup -1/) the expected rate of bare heavy flavor production is high enough to allow for detection schemes which rely on relatively small leptonic branching ratios. These provide a clean separation of the signal from the gluon plus light quark background, while retaining sufficient statistics for further study. The current status of the investigation of lepton-related triggers and cuts is presented, and the jet topologies of events (both signal and background) with high-P/sub T/ leptons are discussed. While these studies have been carried out with samples of high-P/sub T/ q anti q and gluon jets generated with ISAJET, other sources of heavy flavor production at CBA are surveyed.
Date: March 1, 1983
Creator: Aronson, S.; Ogilvie, M.; Stumer, I.; Tanaka, M. & Wanderer, P.
Partner: UNT Libraries Government Documents Department

S s spectroscopy from the LASS (Large Aperture Superconducting Solenoid) spectrometer

Description: A brief summary is presented of results pertinent to s{bar s} spectroscopy derived from high statistics data on K{sup -}p interactions obtained with the LASS spectrometer at SLAC. 21 refs., 10 figs.
Date: December 1, 1989
Creator: Aston, D.; Bienz, T.; Bird, F.; Dunwoodie, W.; Johnson, W.; Kunz, P. et al.
Partner: UNT Libraries Government Documents Department

J sup P = 1 sup minus radial excitations from LASS data

Description: The experimental status of the strange 1 {sup {minus}} mesons is briefly reviewed and compared with the non-strange sector and quark model expectations. The results described are taken from a 4.1 event/nb exposure of the LASS spectrometer to an 11 GeV/e K{sup {minus}} beam.
Date: December 1, 1991
Creator: Aston, D.; Bienz, T.; Bird, F.; Dunwoodie, W.; Johnson, W.B.; Kunz, P. et al.
Partner: UNT Libraries Government Documents Department

The strange 0 sup ++ and 2 sup ++ radial excitations: A review of LASS data

Description: The experimental status of the strange 0{sup ++} and 2{sup ++} mesons is briefly reviewed and compared with expectations from the quark model. The results are taken from a high statistics study of strange mesons produced in LASS by an 11 GeV/c K{sup {minus}} beam. 13 refs., 8 figs., 1 tab.
Date: October 1, 1991
Creator: Aston, D.; Bienz, T.; Bird, F.; Dunwoodie, W.; Johnson, W.B.; Kunz, P. et al.
Partner: UNT Libraries Government Documents Department

Strangeonia and kin; new results from kaon hadroproduction with LASS

Description: Recent results from a high statistics study of strangeonium mesons produced in LASS by an 11 GeV/c K{sup -} beam are reviewed and compared with the quark model. New data from a variety of final states (K*{ovr K*}, {phi}{phi}, {phi}{pi}{sup 0}) produced by hypercharge exchange are described, and compared with results from other hadroproduction modes and from J/{psi} decay. 17 refs., 12 figs.
Date: December 1, 1989
Creator: Aston, D.; Bienz, T.; Bird, F.; Dunwoodie, W.; Johnson, W.B.; Kunz, P. et al.
Partner: UNT Libraries Government Documents Department

New results on hypercharge exchange reactions from LASS

Description: New results from a number of final states ({eta}{pi}{sup {minus}}{pi}{sup +},{bar K}*K*,{phi}{phi}) produced by hypercharge exchange in LASS by an 11 GeV/cK{sup {minus}} beam are described, and compared with results from other hadroproduction modes and from G/{psi} decay.
Date: November 1, 1990
Creator: Aston, D.; Bienz, T.; Dunwoodie, W.; Johnson, W.B.; Kunz, P.; Kwon, Y. et al.
Partner: UNT Libraries Government Documents Department

Two loop partition function in (compactified) heterotic string vacua

Description: Two loop partition function for the heterotic string theory, compactified on any background preserving space-time supersymmetry at the string tree level, is explicitly calculated. This includes E/sub 8/ x E/sub 8/ or SO(32) heterotic string theory in ten dimensional flat space-time.
Date: October 1, 1987
Creator: Atick, J.J. & Sen, A.
Partner: UNT Libraries Government Documents Department