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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
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.
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.
Partner: UNT Libraries Government Documents Department

Five-quark model with flavour-changing neutral current and dimuon events

Description: The recent dimuon data seem to suggest either the necessity of flavor-changing hadronic neutral current or proliferation of quarks beyond charm or both. It is shown how a five-quark model based on simple gauge group SU(2) x U(1) x U(1)&#x27; can generate the flavor-changing, in particular the needed charm-changing, neutral current in a natural fashion. A substantial D/sup 0/--D/sup -0/ mixing can be obtained to account for the &#x27;&#x27;wrong-sign&#x27;&#x27; dimuons observed in ..nu../sub ..mu../-induced reactions. Because of the role of the extra neutral boson in this model, the flavor-changing neutral current is decoupled from leptonic sectors, thus suppressing the trimuon events as experiments indicate thus far.
Date: January 1, 1976
Creator: Kim, J. E. & Kang, K.
Partner: UNT Libraries Government Documents Department

Generalization of the quark rearrangement model. [Quark-parton model]

Description: An extension and generalization of the quark rearrangement model of baryon annihilation is described which can be applied to all annihilation reactions and which incorporates some of the features of the highly successful quark parton model. Some p anti-p interactions are discussed. (JFP)
Date: January 1, 1976
Creator: Fields, T. & Chen, C. K.
Partner: UNT Libraries Government Documents Department

Inclusive charged- and neutral-current antineutrino-proton interactions at high energy. [Cross sections, quark-parton model]

Description: Results on antineutrino-proton interactions observed in the Fermilab 15-foot hydrogen bubble chamber are presented. The charged-current semi-inclusive distributions, as a function of X, Y, Q/sup 2/ and W, are compared with the predictions of the naive quark parton model. Within statistics, no marked dependence of the Y distribution on E/sub nu/ was observed. R/sub anti nu/, the antineutrino neutral-current to charged-current cross section ratio is calculated, and results are presented as a function of R/sub nu/.
Date: January 1, 1976
Creator: Derrick, M.; Dombeck, T. & Hyman, L. G.
Partner: UNT Libraries Government Documents Department

Quantum effects of pseudoparticle size

Description: It is shown that the calculation of quantum effects associated with the classical four dimensional pseudoparticle can be carried to completion in the one loop, lowest order in source approximation, with size effects calculated exactly. The result is finite, and leaves symmetry breaking results intact. For the case of two flavors the theory reduces to a particularly simple form which suggests that the pseudoparticle acts as a source of zero mass bosons which in turn are made of fermion pairs.
Date: January 1, 1976
Creator: Hietarinta, J.; Palmer, W. F. & Pinsky, S. S.
Partner: UNT Libraries Government Documents Department

Quarks and partons. [Review]

Description: This contribution reviews the evidence accumulated over the past year in favor of quarks and partons. Then it applies the quark ideas in order to interpret the neutrino-induced production of charm and the structure of neutral currents.
Date: January 1, 1976
Creator: Paschos, E A
Partner: UNT Libraries Government Documents Department

Topics in lepton-hadron interactions

Description: Review lectures are given on lepton--hadron interactions at high energy--momentum transfers. Included are the inelastic scattering of leptons by nucleons and the process e/sup +/e/sup -/ ..-->.. hadrons. Experimental evidence for the quark--parton picture is reviewed and the more outstanding phenomena: charmed mesons and baryons, Bjorken scaling violation, and new quantum numbers and couplings are discussed. 74 references. (JFP)
Date: January 1, 1976
Creator: Perkins, D. H.
Partner: UNT Libraries Government Documents Department

Virtual quark--quark in the pseudoparticle background. [Quantum fluctuations; four-point functions]

Description: Off-shell four point functions of massless fermions in a pseudoparticle background are calculated. The results are exact to lowest order quantum fluctuations about the classical pseudoparticle field. Only pseudoparticle solutions of unit winding number contribute to the calculated correlation functions. The developed technique requires knowledge only of the zero frequency fermion solutions in the pseudoparticle potential.
Date: January 1, 1976
Creator: Hietarinta, J. & Palmer, W. F.
Partner: UNT Libraries Government Documents Department

Impact parameter study of elastic hadron--proton scattering at 50 and 175 GeV/c. Interim report No. 137. [Differential cross sections, optical model, partial waves]

Description: In hadron-proton collisions at high energies, the impact profile function measures the range and strength of the strong interaction. It determines the effective size and shape of the hadrons involved, for purposes of both elastic scattering and particle production, but depends solely upon the behavior in t of the elastic differential cross-section. Such an analysis of the reactions ..pi.. +- p, K +- p, and p +- p at incident momenta from 50 to 175 GeV/c is presented using the elastic scattering data recently taken. Two derivations of the profile function are given: the classic optical model and the partial wave treatment. The first stresses the ''grey disc'' interpretations of hadrons; both allow the decomposition of the profile into the elastic and inelastic overlap functions, which represent the probabilities of each of the two processes. A more rigorous procedure yielding essentially the same result involves the imposition of unitarity on the relativistic S-matrix and then requiring angular momentum conservation. Cross section measurements extend to t = -0.8 (GeV/c)/sup 2/; this calculation assumes pure exponential behavior thereafter, and accounts for the possibility of a sharp decrease in its slope at larger t. The real part of the scattering amplitude is neglected. The results display good qualitative agreement with the shadow-diffraction scattering model, and with previous analyses. They indicate distinct differences between meson-baryon and baryon-baryon interactions, and imply that dependence of the cross section on energy derives primarily from a net change in peripheral processes. A test of the quark model and the Lipkin sum rules shows substantial deviation from theoretical expectations.
Date: April 1, 1976
Creator: Heltsley, B. K.
Partner: UNT Libraries Government Documents Department

Research in theoretical physics. Annual report, September 1, 1975--August 31, 1976. [Summaries of research activities at Johns Hopkins University]

Description: Results are reported on an algebraic approach to the quark problem, strong coupling approximation to field theories and, spontaneous symmetry breaking in the presence of gravitation. A supersymmetry albebra was constructed which obeys triality exactly and allows for separate conservation of lepton and baryon numbers. The existence of higher lying color singlet states is predicted. Investigations into a perturbation expansion around a strong coupling (''independent valued'') limit of field theories were completed. The result is a generalized classical field theory with correct clustering properties; unitarity is satisfied at the tree diagram level. Vacuum solutions to conformal relativity were found, exhibiting spontaneous symmetry breaking. A ''second Higgs mechanism'' was discovered; as a consequence, scalar mesons are removed from the theory altogether. Significance of the results from the point of view of quark confinement and some cosmological consequences are discussed.
Date: April 1, 1976
Partner: UNT Libraries Government Documents Department

Has hadronic color been excited in neutrino experiments. [Cross sections]

Description: The effect of the massive ''color'' gluon excitation in charged current ..nu..N and anti..nu..N inclusive scattering is studied. The observed rise in sigma/sub c//sup anti..nu..//sigma/sub c//sup ..nu../ and (y)/sup anti..nu../ can be understood as a transient effect arising from the opening of hadronic ''color'' thresholds. This interpretation of the charged current neutrino phenomena does not call for the introduction of the right-handed current of the type (anti pn')/sub R/.
Date: June 1, 1976
Creator: Sidhu, D. P.; Mohapatra, R. N. & Pati, J. C.
Partner: UNT Libraries Government Documents Department

Large p/sub T/ production in 10/sup 4/-10/sup 7/ GeV interactions. [Parton and jet production models]

Description: Evidence for high transverse momentum in cosmic ray interactions is reviewed in the context of models with hard collisions of partons and jet production. Two types of experiments suggest significant production of secondaries with high p/sub T/ above 10/sup 4/ GeV. One compares the cosmic ray data to hard scattering models and discusses further analysis needed to distinguish such models from other possibilities for production of large transverse momentum.
Date: July 1, 1976
Creator: Gaisser, T. K.
Partner: UNT Libraries Government Documents Department

Theoretical particle physics. Progress report, December 1, 1975--November 30, 1976. [Summaries of research activities at Indiana University]

Description: Research can be divided into two categories, the first dealing with the phenomenological treatment of two-body collisions, and the second dealing with symmetry-breaking and charm within the framework of the quark model. A partial-wave amplitude analysis of ..pi../sup +/ proton elastic scattering at incident pion momenta between 1.6 GeV/c and 10 GeV/c has been made. The partial wave amplitudes agree with those at lower momenta and are close to the Regge amplitudes at higher momenta. A number of new ..delta.. resonances are suggested. Also high energy proton-proton scattering was analyzed using Reggeon field theory and a bare pomeron intercept above unity. Furthermore, high energy pion-nucleon charge-exchange data were described by including absorptive corrections to a rho Reggeon exchange. In the second category, meson mass spectra, including predicted masses of charmed mesons, in the quark model using attractive 1/r plus linear confining potentials. The quark model was used to obtain relations among electromagnetic mass splittings of mesons, including charmed mesons, to calculate the pion form factor, and to obtain magnetic moments of baryons. Also restrictions on a quark potential with confinement were discussed in order to obtain linear Regge trajectories. A list of publications is included.
Date: August 1, 1976
Creator: Chu, S. Y.; Hendry, A. W. & Lichtenberg, D. B.
Partner: UNT Libraries Government Documents Department

X spectroscopy and newer particles. [Branching ratios, angular distributions]

Description: Two recent results from the SPEAR Magnetic detector are covered. A study of psi' ..-->.. ..gamma.. + X, ..gamma gamma..psi, ..gamma../sup +/ hadrons is presented; four intermediate states are seen, branching fractions and production angular distribution are given, which agree with the predictions of the charm quark model. Evidence is presented for 2 narrow new states (charges 0 and 1) decaying to a kaon and pions. Structures are seen in the recoil mass spectra. The production and decay characteristics support the assignment of those states as the low lying nonstrange charmed mesons.
Date: August 1, 1976
Creator: Pierre, F.
Partner: UNT Libraries Government Documents Department

Production of charmed meson pairs in electron--positron annihilation

Description: Production of charmed meson pairs of J/sup P/ = 0/sup -/ and 1/sup -/ is examined near the threshold. Production cross sections are parametrized by a quark model of a broken SU(8) symmetry. The charmed hadron production is dominated by (0/sup -/,1/sup -/) pairs, and D* anti D* production comes out to be much too small to reproduce the higher peak in the recoil mass spectrum against D/sup 0/ (anti D/sup 0/) through reflection. A few experimental measurements are pointed out that will clarify the origin of the higher peak of the recoil mass spectrum.
Date: August 27, 1976
Creator: Suzuki, M. & Wada, W. W.
Partner: UNT Libraries Government Documents Department

Asymmetry analysis of target diagrams and mechanism for large transverse momenta. [10/sup 5/ GeV, parton model, quarks]

Description: A quantitative method is described for determining the amount of asymmetry present in target diagrams of secondaries from interactions of very high energy cosmic rays. Such asymmetries must appear if large transverse momenta reported in such experiments at approximately 10/sup 5/ GeV are due to hard scattering of constituents (partons, quarks) in the hadrons. This is currently the accepted explanation of high P/sub T/ phenomena at accelerator energies.
Date: January 1, 1977
Creator: Gaisser, T. K. & Sidhu, D. P.
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.
Partner: UNT Libraries Government Documents Department