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DSE hadron phenomenology.

Description: A perspective on the contemporary application of Dyson-Schwinger equations, focusing on some recent phenomenological applications: a description and unification of light-meson observable using a one-parameter model of the effective quark-quark interaction, and studies of leptonic and nonleptonic nucleon form factors. The theory and phenomenological application of Dyson-Schwinger equations (DSEs) have seen something of a renaissance. For example, they have been applied simultaneously to phenomena as apparently unconnected as low-energy {pi}{pi} scattering, B {r_arrow} D{sup *} decays and the equation of state for a quark gluon plasma, and there are renewed attempts to understand the origin of the infrared enhancement necessary in the kernel of the quark DSE (QCD gap equation) to generate dynamical chiral symmetry breaking (DCSB). Also significant is the appreciation that in this approach current algebra's anomalies remain a feature of the global aspects of DCSB.
Date: May 22, 2000
Creator: Hecht, M. B.; Roberts, C. D. & Schmidt, S. M.
Partner: UNT Libraries Government Documents Department

Spectroscopy and lifetime of bottom and charm hadrons

Description: There are several motivations for studying masses and lifetimes of the hadrons containing a heavy quark, either the bottom or the charm quark. First, the mass and the lifetime are fundamental properties of an elementary particle. Second, the spectroscopy of hadrons gives insights into the QCD potential between quarks. In particular, a symmetry exists for heavy hadrons when the heavy quark mass is taken to be infinite, providing a powerful tool to predict and understand properties of those heavy hadrons. Third, studies of the lifetimes of heavy hadrons probe their decay mechanisms. A measurement of the lifetime, or the total decay width, is necessary when the authors extract magnitudes of elements of the Kobayashi-Maskawa matrix. Again, in the limit of an infinite heavy quark mass things become simple and decay of a heavy hadron should be the decay of the heavy quark Q. This leads to a prediction that all hadrons containing the heavy quark Q should have the same lifetime, that of the quark Q. This is far from reality in the case of charm hadrons, where the D{sup +} meson lifetime is about 2.5 times longer than the D{sup 0} meson lifetime. Perhaps the charm quark is not heavy enough. The simple quark decay picture should be a better approximation for the bottom hadrons because of the larger b quark mass. On the experimental side, the measurements and knowledge of the heavy hadrons (in particular bottom hadrons) have significantly improved over the last decade, thanks to high statistics data accumulated by various experiments. The authors shall review recent developments in these studies in the remainder of this manuscript.
Date: May 15, 2000
Creator: Ukegawa, F.
Partner: UNT Libraries Government Documents Department

Brief report from the Tevatron

Description: The authors report on the B physics prospects from the Fermilab Tevatron, summarizing the B physics goals of the CDF and D0 experiments using their upgraded detectors. They discuss the time schedule for completion of the detector upgrades and summarize the current measurement of the CP violation parameter sin 2{beta} at CDF.
Date: January 24, 2000
Creator: Paulini, M.
Partner: UNT Libraries Government Documents Department

Fully reconstructed hadronic B-decays at CDF

Description: The CDF detector at the Tevatron Collider (Fermilab) has collected data from 1992 to 1995. During these years they performed several measurements by using B hadronic decays. All the analysis exploited lepton triggers. The new measurements the authors present here are on radiative B decays B {r_arrow} K{sup 0*} {gamma}, B {r_arrow} {var_phi}{gamma} and {Lambda}{gamma}. They show also preliminary study for the determination of the branching ratios B {r_arrow} J/{psi}K{sup +}{pi}{sup +}{pi}{sup {minus}} and B {r_arrow} {chi}{sub c} (1P) K{sup +}. In view of Run II they discuss CDF reaches using fully reconstructed B hadronic decays. This is done by scaling the number of events and the efficiencies found in Run I without rely on Monte Carlo simulation whenever it is possible.
Date: July 5, 2000
Creator: Lucchesi, Donatella
Partner: UNT Libraries Government Documents Department

Heavy meson observables via Dyson-Schwinger equations

Description: The authors summarize a Dyson-Schwinger-equation-based calculation of an extensive range of light- and heavy-meson observable, characterized by heavy-meson leptonic decays, semileptonic heavy-to-heavy and heavy-to-light transitions--B {yields} D*, D, {rho}, {pi}; D {yields} K*, K, {pi}, radiative and strong decays--B*{sub (s)} {yields} B{sub (s)}{gamma}; D*{sub (s)}{gamma} and the rare B {yields} K*{sub {gamma}} flavor-changing neutral-current process. In the calculation the heavy-quark mass functions are approximated by constants, interpreted as their constituent-mass: {cflx M}{sub c} = 1.32GeV and {cflx M}{sub b} = 4.65 GeV.
Date: June 28, 2000
Creator: Ivanov, M. A.
Partner: UNT Libraries Government Documents Department

Recent B-physics results at CDF

Description: Between 1992 and 1996 CDF collected about 100 pb{sup {minus}1} of data at a {radical}s = 1.8 TeV at the Fermilab Tevatron collider. This data sample led to a large number of precision measurements of B hadrons properties including their masses, lifetimes and neutral B meson oscillation parameters and the discovery of the B{sub c} meson. Here the author reports on three recent results: the measurement of the B{sup +} production cross section, the search for radiative penguin B hadron decays and the measurement of the CP violating parameter sin 2{beta}. These results are significant examples of the breadth of the CDF program. In 2001 the main injector will allow the Tevatron initially to deliver 1 fb{sup {minus}1} per year at {radical}s = 2 TeV. The CDF detector will undergo major upgrades which will further increase the B physics reach.
Date: July 27, 2000
Creator: Bortoletto, Daniela
Partner: UNT Libraries Government Documents Department

Experimental study of sin 2 {beta} and sin 2 {alpha}

Description: Detailed measurements of CP violation in B meson decay are on the horizon. Here the author reviews the status of current measurements of sin 2{beta} made at LEP and CDF. These yield an average of sin 2{beta} = 0.82 {+-} 0.39, giving 97% confidence that {beta} is greater than 0, evidence that CP violation occurs in B decay. He reviews predictions for the precision one can expect on sin 2{beta} and sin 2{alpha} in the next few years.
Date: March 7, 2000
Creator: Truschuk, W.
Partner: UNT Libraries Government Documents Department

The B {r{underscore}arrow} D*{ell}{nu} form factor at zero recoil

Description: The authors describe a model independent lattice QCD method for determining the deviation from unity for h{sub A{sub 1}}, the B {r{underscore}arrow} D*{ell}{nu} form factor at zero recoil. They extend the double ratio method previously used to determine the B {r{underscore}arrow} D{ell}{nu} form factor. The bulk of statistical and systematic errors cancel in the double ratios they consider, yielding form factors which promise to reduce present theoretical uncertainties in the determination of {vert{underscore}bar}V{sub cb}{vert{underscore}bar}. They present results from a prototype calculation at a single lattice spacing corresponding to {beta} = 5.7.
Date: January 26, 2000
Creator: Simone, J.N.; Hashimoto, S.; El-Khadra, A.X.; Kronfeld, A.S.; Mackenzie, P.B. & Ryan, S.M.
Partner: UNT Libraries Government Documents Department

Charm results on CP violation and mixing

Description: The most recent results on CP violation and mixing in the charm system are reviewed as a guide to the future. While no surprising results are reported so far, charm provides a unique window to physics beyond the Standard Model. The results reported here come from four sources, ALEPH at LEP, E791 and FOCUS/E831 at Fermilab, and CLEO II.V at CESR. Results beyond these sources may be expected as a byproduct of B-motivated experiments.
Date: March 14, 2000
Creator: Appel, J.A.
Partner: UNT Libraries Government Documents Department

CP violation and B mixing in CDF-II

Description: In March 2001, the Tevatron at Fermilab will start a new run at {radical}s = 2.0 TeV, delivering an integrated luminosity of 2 fb{sup {minus}1} in the first two years and more than 15 fb{sup {minus}1} in the following years, before the start of LHC at CERN. CDF has been upgraded to cope with the new physics program. The authors present here the prospects for measuring B mixing and CP violation during the upcoming run.
Date: September 12, 2000
Creator: Ruiz, Alberto
Partner: UNT Libraries Government Documents Department

B and D mesons in lattice QCD

Description: Computational and theoretical developments in lattice QCD calculations of B and D mesons are surveyed. Several topical examples are given: new ideas for calculating the HQET parameters {bar {Lambda}} and {lambda}{sub 1}; form factors needed to determine {vert_bar}V{sub cb}{vert_bar} and {vert_bar}V{sub ub}{vert_bar}; bag parameters for the mass differences of the B mesons; and decay constants. Prospects for removing the quenched approximation are discussed.
Date: October 17, 2000
Creator: Kronfeld, Andreas S.
Partner: UNT Libraries Government Documents Department

Decay Constants of B and D Mesons from Non-pertubatively Improved Lattice QCD

Description: The decay constants of B and D mesons are computed in quenched lattice QCD at two different values of the coupling. The action and operators are ? (a) improved with non-perturbative coefficients where available. The results and systematic errors are discussed in detail. Results for vector decay constants, flavour symmetry breaking ratios of decay constants, the pseudoscalar-vector mass splitting and D meson masses are also presented.
Date: July 1, 2000
Creator: Bowler, K. C.; Debbio, L. Del; Flynn, J. M.; Lacagnina, G. N.; Lesk, V. I.; Maynard, C.M. et al.
Partner: UNT Libraries Government Documents Department