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Heavy Flavor Production From Photons and Hadrons

Description: The present state of the production and observation of hadrons containing heavy quarks or antiquarks as valence constituents, in reactions initiated by real and (space-like) virtual photon or by hadron beams is discussed. Heavy flavor production in e/sup +/e/sup -/ annihilation, which is well covered in a number of recent review papers is not discussed, and similarly, neutrino production is omitted due to the different (flavor-changing) mechanisms that are involved in those reactions. Heavy fla… more
Date: January 1, 1982
Creator: Heusch, C. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Hadron mass estimates in the lattice gauge theory

Description: Some estimates for the hadron masses in lattice QCD are presented in the approximation of neglecting dynamic fermion loops. Both light and heavy quark systems are considered and their dependence on the coupling constant and the quark mass is studied. Some results for the decay amplitudes are also given. We discuss how the eta prime mass can be computed to lowest order in n/sub f/, the number of dynamic fermion flavors.
Date: January 1, 1982
Creator: Hamber, H.
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Partner: UNT Libraries Government Documents Department
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Quark core stars, quark stars and strange stars

Description: A recent one flavor quark matter equation of state is generalized to several flavors. It is shown that quarks undergo a first order phase transition. In addition, this equation of state depends on just one parameter in the two flavor case, two parameters in the three flavor case, and these parameters are constrained by phenomenology. This equation of state is then applied to the hadron-quark transition in neutron stars and the determination of quark star stability, the investigation of strange … more
Date: January 1, 1988
Creator: Grassi, F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Flavor mixing and charm decay

Description: The results of mixing matrix determination and their implications on heavy quark decays are given. The decays of charm mesons D/sup 0/, D/sup +/, F/sup +/ into two pseudoscalar mesons are discussed in the framework of SU(3) symmetry. The charm decays are also discussed in terms of quark diagrams. It is demonstrated that the differences observed in the lifetimes of D/sup 0/ and D/sup +/, and in the branching ratios B(D/sup 0/ ..-->.. K/sup -/K/sup +/) and B(D/sup 0/ ..-->.. ..pi../sup -/..pi../s… more
Date: January 1, 1980
Creator: Chau Wang, L.C.
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Partner: UNT Libraries Government Documents Department
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Construction of. Delta. m sup 2 --sin sup 2 2. theta. plots

Description: In the two-flavor approximation, the probability for a neutrino to oscillate from one flavor to the other is given by {Rho}{sub {nu}a}{yields}{sub {nu}b} = sin{sup 2} 2{theta} sin{sup 2} (1.27 {Delta}m{sup 2} L/E{sub {nu}}) where {theta} is the mixing angle, {Delta}m{sup 2} = {vert bar}m{sub {nu}a}{sup 2} {minus} m{sub {nu}b}{sup 2}{vert bar} is measured in (eV/c{sup 2}){sup 2}, L, the distance from the source, is measured in km, and E, the beam energy, is measured in GeV. If either {Delta}m{su… more
Date: January 1, 1991
Creator: Snyder, R. (Oberlin Coll., OH (United States). Dept. of Physics) & Goodman, M. (Argonne National Lab., IL (United States))
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Partner: UNT Libraries Government Documents Department
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Thermodynamics of lattice QCD with 2 light dynamical (staggered) quark flavours on a 16 sup 3 times 8 lattice

Description: Lattice QCD with 2 light staggered quark flavours is being simulated on a 16{sup 3} {times} 8 lattice to study the transition from hadronic matter to a quark gluon plasma. We have completed runs at m{sub q} = 0.0125 and are extending this to m{sub q} = 0.00625. We also examine the addition of a non-dynamical strange'' quark. Thermodynamic order parameters are being measured across the transition and further into the plasma phase, as are various screening lengths. No evidence for a first order t… more
Date: January 1, 1991
Creator: Gottlieb, S.; Krasnitz, A. (Indiana Univ., Bloomington, IN (United States). Dept. of Physics); Heller, U.M.; Kennedy, A.D. (Florida State Univ., Tallahassee, FL (United States). Supercomputer Computations Research Inst.); Kogut, J.B. (Illinois Univ., Urbana, IL (United States). Dept. of Physics); Liu, W. (Thinking Machines Corp., Cambridge, MA (United States)) et al.
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Partner: UNT Libraries Government Documents Department
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Flavor production in e sup + e sup - annihilation and in proton- proton interactions

Description: We compare the p{sub T} dependence of pion, kaon and proton production cross sections in the central rapidity region of e{sup {plus}}e{sup {minus}} annihilation events and in proton-proton collisions at ISR energies. We find similarities both in the p{sub T} dependence of cross sections and in the particle composition as a function of p{sub T}, in agreement with the hypothesis of a universal mechanism of particle production. 13 refs., 4 figs.
Date: January 1, 1986
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Partner: UNT Libraries Government Documents Department
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Factorization at small x

Description: We show how to modify the Lipatov equation to treat short distance cross sections in the factorization theorem.
Date: January 1, 1990
Creator: Collins, J.C. (Pennsylvania Univ., Philadelphia, PA (USA). Dept. of Physics Argonne National Lab., IL (USA)) & Ellis, R.K. (Fermi National Accelerator Lab., Batavia, IL (USA))
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Partner: UNT Libraries Government Documents Department
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Heavy quark production by neutrinos and antineutrinos. [Quark-parton model, SU(2) x SU(2) x U(1) gauge group, 200 GeV]

Description: The rate for producing t- and b-quarks in, respectively, neutrino and antineutrino interactions with nucleons are estimated. Experimental quark parton distribution functions, SU(2) x SU(2) x U(1) gauge group mixing angles, and threshold suppression through rescaling are used in the calculation. The ratios to total cross sections of b-quark production by anti nu, R/sub b//sup anti nu/, and t-quark production by ..nu.., R/sub t//sup nu/, are, respectively, R/sub b//sup anti nu/ approximately equa… more
Date: January 1, 1979
Creator: Scott, D. M. & Tanaka, K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Gluonia. [Xi-2200 resonances]

Description: The postulated existence of hadrons with no quark content, implied by the non-Abelian nature of quantum chromodynamics, has been the object of much experimental activity. Recent data from radiative psi decay permit a confrontation of available evidence with the most simple-minded criteria for their appearance. In the absence of compellingly positive evidence we give a rating of the relative merits of several possible candidates. 36 references, 17 figures.
Date: January 1, 1985
Creator: Heusch, C.A.
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Partner: UNT Libraries Government Documents Department
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Study of heavy flavored particles

Description: This report discusses progress on the following topics: time-of- flight system; charmed baryon production and decays; D decays to baryons; measurement of sigma plus particles magnetic moments; and strong interaction coupling. (LSP)
Date: January 1, 1991
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Search for the production of a new quark flavor at the highest PETRA energies. [33 to 35. 8 GeV (c. m. )]

Description: A study of hadron production in e/sup +/e/sup -/ collisions at the highest PETRA energies reached so far is reported. Production of a new quark flavor was sought at cms energies of 33, 35, and 35.8 GeV. The measured values of the total cross section, the thrust distributions, and the study of inclusive muon production show no evidence for the production of a new charge 2/3e quark near threshold. In addition, during an energy scan zn the region 29.9 less than or equal to ..sqrt..s less than or e… more
Date: January 1, 1980
Creator: Barber, D. P.; Becker, U.; Benda, H.; Beohm, A.; Branson, J. G.; Bron, J. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Search for the top quark with CDF

Description: During the 1988--89 Tevatron Collider run the CDF detector has collected data for an integrated luminosity of 4.4 pb{sup {minus}1}. The sample has been used to search for the top quark in several topologies. Preliminary results show that a top mass below 89 GeV is excluded at the 95% confidence level, thus extending the limit of 77 GeV previously published by CDF. 14 refs., 8 figs.
Date: January 22, 1991
Creator: Barbaro-Galtieri, A. (Lawrence Berkeley Lab., CA (USA))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Flavor symmetry in the large N sub c limit

Description: An essential difference between two-flavor and three-flavor descriptions of baryons in large N{sub c} QCD is discussed in detail. For N{sub c}{ge}3 a state with the SU(3) flavor quantum numbers of the proton must contain a number of strange quarks n{sub s}{ge}(N{sub c}{minus}3)/3, while a state with no strange quarks must have extra hypercharge Y{minus}1 = 3/N{sub c}{minus}1. The extra strangeness or extra hypercharge which vanishes for N{sub c} = 3 is spurious for the physical proton. This pro… more
Date: January 1, 1991
Creator: Karl, G. & Lipkin, H. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Flavor changing neutral current transitions on the lattice for heavy-light systems

Description: Flavor changing neutral current transitions are a very important test of the standard model. Some of the channels can also be very useful for extracting the Kobayashi-Maskawa mixing matrix elements. However, their potential applications are limited by the uncertainties in the relevant hadronic matrix elements. We show that these matrix elements are also amenable to lattice techniques. In this study, we focus on radiative transitions such as B {yields} K*{gamma} and present preliminary results o… more
Date: January 1, 1992
Creator: Bernard, C.W. (Washington Univ., St. Louis, MO (United States). Dept. of Physics); Hsieh, P.F. & Soni, A. (Brookhaven National Lab., Upton, NY (United States))
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Partner: UNT Libraries Government Documents Department
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Study of quark flavor-dependence in exclusive reactions at large momentum transfers

Description: The measurement of exclusive reactions at large momentum transfers provides an important testing ground for models of hard quark-quark scattering. We have measured cross sections or set upper limits for 12 meson-bryon (..pi../sup +-/p ..-->.. p..pi../sup +-/, p/rho//sup +-/, ..pi../sup +/..delta../sup +-/, K/sup +/..sigma../sup +-/, ..pi../sup /minus//p ..-->.. ..lambda../sup 0//..sigma../sup 0/K/sup 0/, K/sup +-/p ..-->.. pK/sup +-/) and 2 baryon-baryon (p/sup +-/p ..-->.. pp/sup /plus minus/)… more
Date: January 1, 1988
Creator: Carroll, A. S.; Appel, R.; Barton, D. S.; Bunce, G.; Kmit, M.; Makdisi, Y. I. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Exotic mesons

Description: I discuss the status of exotic mesons--states that do not fit into the simple q/bar q/ model. 17 refs., 1 fig.
Date: January 1, 1988
Creator: Close, F.E.
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Partner: UNT Libraries Government Documents Department
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Neutrino masses, mixing, moments, and matter

Description: The present status of neutrino masses, mixing, and electromagnetic moments is surveyed. Potential enhancements of neutrino oscillations, decay, and spin-flavor precession due to their interactions with matter are described.
Date: January 1, 1988
Creator: Marciano, William J.
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Partner: UNT Libraries Government Documents Department
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Light quark spectroscopy

Description: Recent data, in particular from LASS and GAMS, are beginning to give a rather clear picture of the spectroscopy of mesons composed of u, d, and s flavors. Details of the radial excitations are now appearing. It may become possible to identify gluonic or molecular and multiquark states by their failure of fit into the emerging q/bar q/ spectrum. An ''anti-selection rule'' for gluonic hadrons is presented. 20 refs., 3 figs., 1 tab.
Date: January 1, 1988
Creator: Close, F.E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Flavor symmetry and the spin of the proton

Description: The analysis of the EMC result on the quark contribution to the spin of the proton has been challenged because of the use of SU(3) symmetry is shown not to be needed to obtain peculiar results about these quark contributions. The analysis without assuming flavor symmetry allows the quark contribution to the proton spin to be large, but only if it is due to the strange quarks, with the nonstrange quark contribution opposite to the spin of the proton. Recent data from the European Muon Collaborat… more
Date: January 1, 1988
Creator: Lipkin, Harry J.
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Partner: UNT Libraries Government Documents Department
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Concluding remarks and outlook: Europhysics conference on flavor-mixing in weak interactions

Description: Some comments are offered on the present knowledge of the mixing matrix of Kobayashi and Maskawa and of the dynamics of nonleptonic decay. Also, remarks are made concerning CP violation. Plans for research from 1984 to 1989 are listed briefly. The history of studies on weak interactions is briefly reviewed, and several unanswered questions are stated, such as where are the truth particles, how may they be discovered, what is the mass-generating mechanism for the gauge bosons, how many Z/sup 0/'… more
Date: January 1, 1984
Creator: Chau, L. L.
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Partner: UNT Libraries Government Documents Department
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Theoretical expectations for T-violation in the nucleon-nucleon interaction

Description: The possible size of T-violating effects in the N-N interaction are considered both with and without P-violation. For T-violation it is found that in several gauge models P,T-violating effects in the N-N interaction could be large enough to be observable in some current and contemplated experiments. Concerning P-conserving T-violating effects it is noted that in gauge models with elementary quarks the flavor-conserving nonleptonic interactions of the quarks do not contain in first order a P-con… more
Date: January 1, 1987
Creator: Herczeg, P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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