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Baryon-antibaryon systems. [Molecular states, bound and resonant anti-B B states, many-body systems]

Description: A few simple situations involving the anti-B--B and B-nucleus systems are discussed in the nonrelativistic dynamical treatment that is hopefully justified by the particular nature of the elementary two-body states considered. Of particular relevance is the spectroscopy of nucleons, isobars and mesons as three-quark or two-quark composites. Anti-B-B molecular states, bound and resonant anti-B--B states, and many-body systems are considered. 22 references. (JFP)
Date: unknown
Creator: Kahana, S H
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department

Conditions for renormalizability of quantum flavor dynamics

Description: The presence of a new anomaly, in addition to the Adler-Bell-Jackiw (ABJ) anomaly, is shown for gauge theories with ..gamma../sub 5/ couplings. The ABJ anomaly is discussed first by shifting variable of a linearly-divergent integral, then by dimensional regularization. Using the second method, the general nonabelian case is considered, in the presence of an overlapping divergence. A new anomaly is discovered which is not, in general cancelled by the usual restrictions because fermion masses are involved, assuming no cancellation between different Feynman diagrams, and current-algebra quark masses, then leads to the conclusion that the standard model of quantum flavor dynamics (i.e., that of Glashow, Salam, Ward, Weinberg, Kobayashi and Maskawa) is non-renormalizable. Imposition of renormalizability dictates that new dynamical constraints be met. Hence, only that part of the quark mass corresponding to the lepton mass in the same quark-lepton generation is generated by the electroweak interactions. The remaining mass comes presumably from the strong interaction for which the dynamical theory must therefore have at least some flavor dependence; this is not the case for e.g., quantum chromodynamics which is totally flavor-blind. 48 references.
Date: unknown
Creator: Frampton, P.H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department

String flip-flop and quark matter

Description: Quarks are bound by strings attached to them. When two strings come close, a rearrangement of connections takes place. This effect plays an important role in a dense ensemble of quarks, quark matter. A phase transition from nuclear matter to quark matter occurs at the nucleon density rho < 5 rho/sub 0/ where rho/sub 0/ is the density of the ordinary nuclear matter. The string flip-flop causes a new type of attractive interaction between hadrons at short distances or among quarks at high density. This interaction can produce multiquark bound states such as dibaryon or dimeson resonant states. 8 references.
Date: unknown
Creator: Miyazawa, H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department

Cabibbo current and CP violation in a six quark gauge model

Description: The extended Cabibbo current in a six quark gauge model is obtained in terms of Eulerian angles theta/sub c/, phi and psi which are functions of quark mass ratios and phases in the quark mass matrices. Particular attention is paid to arbitrary phases that lead to CP violation. In the limit m/sub u//m/sub c/ ..-->.. 0 there is no CP violation for parallel ..delta..S parallel = 1 processes. Some phenomenological results of the model are discussed.
Date: January 1, 1977
Creator: Hagiwara, T.; Kitazoe, T.; Mainland, G.B. & Tanaka, K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department

High p/sub perpendicular/ and jets. [Quark-parton model]

Description: Estimates are made of the cross section for producing high momentum particles and jets at Isabelle using two different models one that fits the data but has no theoretical basis, and one based on theory but which does not fit the data. The purpose of these estimates is to give a range of expectations for Isabelle, and not to suggest tests of these models. In both models it is assumed the proton is made up of quark-partons with structure functions determined in large part from deep inelastic lepton-proton scattering. 5 references. (JFP)
Date: January 1, 1977
Creator: Trueman, T.L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department

Theory of spin dependence at very high energies. [Review, S matrix]

Description: The point of view taken is to introduce a number of topics for possible discussion during the course of this workshop. Some of the theoretical expectations for polarization phenomena are reviewed assuming that hadrons are composite. Polarization phenomena are considered from an S-matrix point of view.
Date: January 1, 1977
Creator: Thomas, G.H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department

Yang--Mills vacua in Landau gauge

Description: A vacuum gauge field A/sub ..mu..//sup a/ for Yang-Mills theory is constructed; this field is pure vacuum (A/sub ..mu..//sup a/ = 0) at the origin, approaches at large distances, the Belavin-Polyakov-Schwartz-Tyupkin pseudo-particle, and satisfies delta/sub ..mu../A/sub ..mu..//sup a/ = 0 everywhere. The net topological charge is zero, and there is a Dirac-like string terminating at the origin.
Date: January 1, 1977
Creator: Frampton, P.H.; Hagiwara, T.; Palmer, W.F. & Pinsky, S.S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department

Prompt leptons and hadronic jets from W mesons. [SU(2) x U(1) quark model]

Description: The signal/background ratio for the decay of the W into hadronic jets, it is affirmed, should be improved by a factor of about 15 if a prompt lepton is required. For definiteness the hadronic decays of the W/sup +/ in an SU(2) x U(1) model with six quarks is considered. (JFP)
Date: August 22, 1977
Creator: Paige, F.E. & Palmer, R.B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department

Self-consistent model calculations of the ordered S-matrix and the cylinder correction

Description: The multiperipheral ordered bootstrap of Rosenzweig and Veneziano is studied by using dual triple Regge couplings exhibiting the required threshold behavior. In the interval -0.5 less than or equal to t less than or equal to 0.8 GeV/sup 2/ self-consistent reggeon couplings and propagators are obtained for values of Regge slopes and intercepts consistent with the physical values for the leading natural-parity Regge trajectories. Cylinder effects on planar pole positions and couplings are calculated. By use of an unsymmetrical planar ..pi..--rho reggeon loop model, self-consistent solutions are obtained for the unnatural-parity mesons in the interval -0.5 less than or equal to t less than or equal to 0.6 GeV/sup 2/. The effects of other Regge poles being neglected, the model gives a value of the ..pi..--eta splitting consistent with experiment. 24 figures, 1 table, 25 references.
Date: November 1, 1977
Creator: Millan, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department

Inverse scattering problem for quarkonium systems. I. One-dimensional formalism and methodology. [bound state, algebraic technique]

Description: The inverse scattering formalism for reflectionless potentials is applied to the reconstruction of confining potentials from bound-state properties. An explicit algebraic technique is presented and tested on several one-dimensional examples. The connection with a classical problem of interacting solitons is exhibited. 27 references.
Date: December 1, 1977
Creator: Thacker, H.B.; Quigg, C. & Rosner, J.L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department

Cabibbo angle in a six quark gauge model. [Mass matrices]

Description: General structures of the mass matrices resulting from a quark-Higgs Yukawa interaction are discussed. It is assumed that there are two sets of Higgs bosons in a six quark SU(2)/sub L/ x SU(2)/sub R/ x U(1) gauge model and require that the interaction be invariant under a general discrete symmetry. Three physically acceptable mass matrices are found including those of Fritzsch, and Hagiwara et al. Special attention is paid to the phase of the vacuum expectation value of the Higgs boson, which is related to CP violation. A mass relation among six quarks, m/sub t/ = m/sub b/ ..sqrt.. m/sub u/m/sub c//m/sub d/m/sub s/ is obtained for the latter models. No new mass matrices are found when there are three sets of Higgs bosons.
Date: January 1, 1978
Creator: Kitazoe, T. & Tanaka, K.
Item Type: Refine your search to only Report
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.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department

Higgs scalar in vector meson decays. [T(20,000), (25,000), (30,000) postulated; decay widths, cross sections, triangle diagram]

Description: For the (anti tt) bound-state which is designated T, expected to be discovered shortly, the leptonic and hadronic decay widths, and the production cross section in e/sup +/e/sup -/ annihilation are studied. For both Y(9.5,anti bb) and T, the decay into Higgs scalar plus photon is calculated, employing a triangle diagram estimate for the dependence of this decay matrix element on the Higgs mass. Provided that the Higgs mass is less than the masses of the vector mesons, the decay should be observable.
Date: January 1, 1978
Creator: Frampton, P.H. & Wada, W.W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department

High energy physics studies. Progress report. Part I. Experimental program. Part II. Theoretical program. [Summaries of research activities at Ohio State University]

Description: Experimental Program: assembly of an experiment as Fermilab E-531 to measure decay lifetimes, with tagged emulsion of charmed particles produced by high energy neutrinos was finished, and data taking now is in progress. An experiment to measure prompt neutrino production at Fermilab, E-613, was approved and detailed design of it is continuing. Search for parity violation in scattering of polarized protons, an experiment E-446-ZGS at ANL, was performed with the sensitivity of 10/sup -6/ for detection of that process and yielded null results. Another run with improved sensitivity of 10/sup -7/ is in preparation. Data analysis of the neutrino experiment E-310 at Fermilab will continue. Trimuon events, a new discovery, were identified in those data. Analysis of data on meson production from experiments performed at the ZGS--ANL, E-397, E-420 and E-428, with charged and neutral spectrometer will continue. A new relatively broad resonance (T approx. 70 MeV) with quantum numbers IJ/sup P/ = 00/sup -1/ was discovered in the data from E-397. Analysis of beta decay of polarized ..sigma../sup -/ hyperons is in progress. Participation in the design of the experimental areas for the Isabelle colliding proton beam accelerator will continue. Theoretical Program: topics which will be investigated in the coming year are: the instanton-anti-instanton QCD gauge fields, discrete symmetries which may determine quark masses in the SU(2) x U(1) model, calculation of charmed meson production in e/sup +/e/sup -/ collisions and formation of gluon jets, Higgs boson production in pp collisions, calculation of Higgs boson mass in terms of vector boson mass, study of Lagrangians with gauge and Higgs scalar fields, investigation of Faddeev--Popov determinants as related to quantum chromodynamics, a study of quantum flavor dynamics and anomalies in the axial vector Ward identity and a study of super symmetry as a part of a realistic model of leptonic ...
Date: January 1, 1978
Creator: Romanowski, T.A.; Tanaka, K. & Wada, W.W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department

Kaons and antiprotons as probes of the nucleus

Description: The K/sup +/ absorption on nuclei as a probe is considered, in particular the extraction of neutron densities from elastic and total cross sections, inelastic scattering to particular residual nuclear states, and quasiparticle properties of more deeply bound nucleon orbitals in the shell model via the (K/sup +/, K/sup +/p) reaction and K/sup +/ scattering with large energy loss (deep inelastic processes). It is noted that the level ordering of clumps of states reveals important features of the ..lambda..N interaction, possible formation of strangeness S = 2 nuclear systems, and hypernucleus formation. A new class of mesons is formed in the particle - antiparticle interactions. This formation may be as loosely bound quasimolecular ensembles of baryon and antibaryon or composed of a diquark and an anti-diquark. (JFP)
Date: January 1, 1978
Creator: Dover, C.B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department

Massive lepton pair production in hadronic collisions. [Review, Drell-Yan quark annihilation, scaling violations]

Description: A review is presented of theoretical attempts to describe the massive lepton pair continuum produced in hadronic collisions. Beginning with the classical Drell-Yan quark-antiquark annihilation model, its expectations are compared with data. Scaling violations and corrections to the Drell-Yan pictured are discussed. Next, original work is presented bearing on the understanding of the transverse momentum distributions of the dileptons. In a parton model, the quark-gluon scattering graphs which provide scaling violations also endow the dileptons with relatively large (P/sub T/). Comparisons with available data support these QCD expectations; further tests of the QCD predictions are proposed. Implications are drawn for W production experiments, and predictions are presented for reactions initiated by antiprotons.
Date: January 1, 1978
Creator: Berger, E.L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department

Neutral current constraints on gauge models of weak and electromagnetic interactions

Description: Recent studies by Sehgal and Hung and Sakurai suggest that neutrino hadron neutral current couplings must lie in one of two allowed regions in coupling parameter space. Their analyses are extended using realistic BNL/sub ..nu mu../ and anti ..nu../sub ..mu../ spectra in the elastic ..nu../sub ..mu../P (anti ..nu../sub ..mu../P) calculations and also constraints imposed by the q/sup 2/-distributions are studied. Also these results are compared with a variety of gauge models. The Weinberg-Salam and SU(2)/sub L/ x SU(2)/sub R/ x U(1) models fall within one allowed region, while a vectorlike SU(3) x U(1) model and a hybrid SU(2) x U(1) model with a (u,b)/sub R/ doublet fall in the other region.
Date: January 1, 1978
Creator: Langacker, P. & Sidhu, D.P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department

New anomaly in axial-vector ward identity

Description: It is shown how a new type of anomaly, in addition to the Adler--Bell--Jackiw anomaly, can occur in a gauge theory with ..gamma../sub 5/ couplings. Such an anomaly renders standard theories of quantum flavor dynamics nonrenormalizable. 19 references.
Date: January 1, 1978
Creator: Frampton, P.H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department

New approach to lepton pair production. [Thermal parton model]

Description: Arguments are first presented to suggest that perturbative QCD calculations cannot account for the average transverse momentum <q/sub T/> of the dileptons observed in hadronic collisions at present energies. Regarding the complication as being due to the many gluon interactions in the initial state, a thermal parton model is considered which is a combination of the thermodynamical model and the usual parton model. With practically no free parameter the observed features of <q/sub T/> can be reproduced with the correct dependences on the incident energy and the mass and rapidity of the dileptons.
Date: January 1, 1978
Creator: Hwa, R. C. & Lam, C. S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department

New results on dimuon production by high energy neutrinos and antineutrinos. [Rates, GIM model]

Description: The rates for neutrino induced ..mu../sup -/..mu../sup +/, ..mu../sup -/..mu../sup -/, and ..mu../sup -/..mu../sup -/..mu../sup +/ events all relative to the charge-current interaction rate are presented. It is shown that the data suggest that a ..nu..-induced prompt ..mu../sup -/..mu../sup -/ signal may in fact exist. But no clear evidence has as yet been established for prompt ..mu../sup -/..mu../sup -/ events from anti ..nu.. interactions. It is shown that both the rates and properties of the opposite-sign dimuon events are consistent with the GIM model. Based on this model these data may be used to determine f/sub s/, the amount of strange quark relative to valence d-quark in the nucleon. The data give approximately f/sub s/ approximately tan/sup 2/theta/sub c/ = 0.05. 13 references. (JFP)
Date: January 1, 1978
Creator: Ling, T.Y.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department