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The Supersymmetric Fat Higgs

Description: Supersymmetric models have traditionally been assumed to be perturbative up to high scales due to the requirement of calculable unification. In this note I review the recently proposed `Fat Higgs' model which relaxes the requirement of perturbativity. In this framework, an NMSSM-like trilinear coupling becomes strong at some intermediate scale. The NMSSM Higgses are meson composites of an asymptotically-free gauge theory. This allows us to raise the mass of the Higgs, thus alleviating the MSSM of its fine tuning problem. Despite the strong coupling at an intermediate scale, the UV completion allows us to maintain gauge coupling unification.
Date: October 27, 2004
Creator: Harnik, Roni
Partner: UNT Libraries Government Documents Department

Rare and forbidden decays of D Mesons

Description: The authors summarize the results of two recent searches for flavor-changing neutral current, lepton-flavor violating, and lepton-number violating decays of D{sup +}, D{sub s}{sup +}, and D{sup 0} mesons (and their antiparticles) into modes containing muons and electrons. using data from Fermilab charm hadroproduction experiment E791, they examined D{sup +} and D{sub s}{sup +} {pi}{ell}{ell} and {Kappa}{ell}{ell} decay modes and the D{sup 0} dilepton decay modes containing either {ell}{sup +}{ell}{sup {minus}}, a {rho}{sup 0}, {bar {Kappa}}*{sup 0}, or {phi} vector meson, or a non-resonant {pi}{pi}, {Kappa}{pi}, or {Kappa}{Kappa} pair of pseudoscalar mesons. No evidence for any of these decays was found. Therefore, the authors presented branching-fraction upper limits at 90% confidence level for the 51 decay modes examined. Twenty-six of these modes had no previously reported limits, and eighteen of the remainder were reported with significant improvements over previously published results.
Date: May 23, 2001
Creator: al., David A. Sanders et
Partner: UNT Libraries Government Documents Department

Measurement of A{sub c} with charmed mesons at SLD

Description: We present a direct measurement of the parity-violation parameter A{sub c}. The measurement is based on 550k Z{sup 0} decays collected by the SLD detector. The mean electron-beam polarization is |P{sub e}| = 73%. The tagging of c-quark events was performed using two methods: The exclusive reconstruction of D*{sup +}, D{sup +}, and D{sup 0} mesons, and the inclusive P{sub T} spectrum of soft-pions ({pi}{sub s}) in the decay of D*{sup +} {yields} D{sup 0}{pi}{sub s}{sup +}. The results of these two methods are combined to give A{sub c} = 0.688 {+-} 0.035(stat.) {+-} 0.025(sys.) (preliminary).
Date: July 16, 1999
Creator: Iwasaki, Masako
Partner: UNT Libraries Government Documents Department

B physics at the tevatron

Description: Precision B-physics results from the CDF and D0 Collaborations based on data collected during the Tevatron 1992-96 run are presented. In particular we discuss the measurement of the B{sub s} meson lifetime, B{sub c} meson observation, and B{sup 0} - {anti B}{sup 0} mixing results obtained using time-evolution analyses. Prospects for the next Tevatron run, starting in 1999, are also reported.
Date: July 1, 1998
Partner: UNT Libraries Government Documents Department

Electromagnetic Mass Splittings in Heavy Mesons

Description: The electromagnetic contribution to the isomultiplet mass splittings of heavy mesons is reanalyzed within the framework of the heavy mass expansion. It is shown that the leading term in the expansion is given to a good approximation by the elastic term. 1/mQ-corrections can only be estimated, the main source of uncertainty now being inelastic contributions. The 1/mQ-corrections to the elastic term turn out to be relatively small in both D and B mesons.
Date: November 1, 1992
Creator: Goity, Jose
Partner: UNT Libraries Government Documents Department

New puzzles in nonleptonic B and D decays

Description: Exclusive charged B decays show an unexplained enhancement in low-lying channels which must be reversed in other channels to equalise charged and neutral lifetimes. One suggested explanation involves decay modes with excited mesons like the a{sub 1}. The anomalous behavior of decay modes of D and B mesons into final states containing the {eta} and {eta}{prime} mesons is discussed.
Date: September 1, 1997
Creator: Lipkin, H.J.
Partner: UNT Libraries Government Documents Department

Search for rare 3 and 4-body D0 decays at FNAL E791

Description: Limits at the 10{sup -4} level are reported for rare and forbidden decays of the D{sup 0} charm meson to a pair of leptons and either a vector meson or two pseudoscalar mesons. Of these searches, 18 are investigations of decays without previous published results; several others have significantly improved sensitivity over previous results.
Date: June 12, 2001
Creator: Summers, Donald J.
Partner: UNT Libraries Government Documents Department

On constraints for heavy-meson form factors

Description: We examine the recent work of de Rafael and Taron where model-independent bounds on the Isgur-Wise function are presented. We first argue that the bounds cannot hold in as much generality as implied. We show that the effects of resonances omitted in their discussion (such as heavy-heavy ``onium`` states below threshold) modify the bound. The resulting bound is much weaker but may be useful where the size of the additional contribution may be computed or estimated.
Date: November 1, 1992
Creator: Grinstein, B. & Mende, P.F.
Partner: UNT Libraries Government Documents Department

Time dependent B{sup 0} {anti B}{sup 0} mixing at CDF

Description: WE describe two measurements of {Delta}{ital m}{sub d}. The first uses {ital B} {r_arrow} {ital vlD}{sup (*)} events and a same-side flavor tagging algorithm. the second uses dilepton events. From the average of these two measurements we find {Delta}{ital m}{sub d} = 0. 466 {+-}0.037{+-} 0.031 ps{sup -1}.
Date: November 1, 1996
Creator: CDF Collaboration
Partner: UNT Libraries Government Documents Department

Hot Topics from the BABAR Experiment

Description: With a sample of about 384 million B{bar B} pairs recorded with the BABAR detector, we search for the flavor-changing charged current transition B{sup {+-}} {yields} {tau}{+-}{upsilon} and perform an amplitude analysis of the effective flavor-changing neutral current transition B{sup {+-}} {yields} {var_phi}(1020)K*(892){+-}. We also extend our search for other K* final states in the decay B{sup 0} {yields} {var_phi}(1020)K*0 with a large K*0 {yields} K{sup +}{pi}{sup -} invariant mass. Two samples of events with one reconstructed hadronic B decay or one reconstructed semileptonic B decay are selected, and in the recoil a search for B{sup {+-}} {yields} {tau}{+-}{upsilon} is performed. We find a 2.6 {sigma} (3.2 {sigma} not including expected background uncertainty) excess in data which can be converted to a preliminary branching fraction central value of {beta}(B{sup {+-}} {yields} {tau}{+-}{upsilon}) = (1.20{sup +0.40+0.29}{sub -0.38-0.30} {+-} 0.22) x 10{sup -4}. With the decay B{sup {+-}} {yields} {var_phi}(1020)K*(892){sup {+-}}, twelve parameters are measured, where our measurements of f{sub L} = 0.49 {+-} 0.05 {+-} 0.03, f{sub {perpendicular}} = 0.21 {+-} 0.05 {+-} 0.02, and the strong phases point to the presence of a substantial helicity-plus amplitude from a presently unknown source.
Date: June 15, 2007
Creator: Gritsan, A.V. & U., /Johns Hopkins
Partner: UNT Libraries Government Documents Department

B Decays Involving Light Mesons

Description: Recent BABAR results for decays of B-mesons to combinations of non-charm mesons are presented. This includes B decays to two vector mesons, B {yields} {eta}{prime}({pi}, K, {rho}) modes, and a comprehensive Dalitz Plot analysis of B {yields} KKK decays.
Date: January 9, 2007
Creator: Eschrich, Ivo Gough & /UC, Irvine
Partner: UNT Libraries Government Documents Department

B and D Meson Decay Constants

Description: We present an update of our calculations of the decay constants of the D, D{sub s}, B, and B{sub s} mesons in unquenched 2+1 flavor QCD. We use the MILC library of improved staggered gauge ensembles at lattice spacings 0.09, 0.12, and 0.15 fm, clover heavy quarks with the Fermilab normalizations, and improved staggered light valence quarks.
Date: April 1, 2009
Creator: Bernard, C.; DeTar, C.; Di Pierro, M.; El-Khadra, A. X.; Evans, R. T.; Freeland, Elizabeth Dawn et al.
Partner: UNT Libraries Government Documents Department

On Decays of B Mesons to a Strange Meson and an Eta or Eta' Meson at Babar

Description: We describe studies of the decays of B mesons to final states {eta}K{sup *}(892), {eta}K{sup *}{sub 0}(S-wave), {eta}K{sup *}{sub 2}(1430), and {eta}'K based on data collected with the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} collier at the Stanford Linear Accelerator Center. We measure branching fractions and charge asymmetries for the decays B {yields} {eta}K{sup *}, where K{sup *} indicates a spin 0, 1, or 2 K{pi} system, making first observations of decays to final states {eta}K{sup *0}{sub 0}(S-wave), {eta}K{sup *+}{sub 0} (S-wave), and {eta}K{sup *0}{sub 2}(1430). We measure the time-dependent CP-violation parameters S and C for the decays B{sup 0} {yields} {eta}'K{sup 0}, observing CP violation in a charmless B decay with 5{sigma} significance considering both statistical and systematic uncertainties..
Date: April 21, 2009
Creator: Hirschauer, James Francis
Partner: UNT Libraries Government Documents Department

Measurement of B{sup 0}/Bbar{sup 0} {right arrow}J/{psi} K(0 over s) decay asymmetry using same-side b-flavor tagging

Description: We present a measurement of the time-dependent asymmetry in the rate for {anti B}{sup 0} versus B{sup 0} decays to J/{psi}K{sup 0}{sub s}. The data sample consists of 198 {+-} 17 B{sup 0}/{anti B}{sup 0} decays collected by the CDF detector in p{anti p} collisions at the Fermilab Tevatron, where the initial b flavor has been determined by a same-side flavor tagging technique. This asymmetry is interpreted in the Standard Model as a measurement of the CP-violation parameter sin(2{beta}). Our analysis results in sin(2{beta}) = 1:8 {+-} 1:1(stat) {+-} 0:3(syst).
Date: October 1, 1998
Creator: Tseng, J.
Partner: UNT Libraries Government Documents Department

Semirelativistic constituent-quark model with goldstone-boson-exchange hyperfine interactions.

Description: We address the semirelativistic constituent-quark model with linear confinement and a hyperfine interaction deduced from Goldstone-boson exchange. In the version where the latter is represented by pseudoscalar meson exchange ({pi}, K, {eta}, {eta}{prime})and restricted to the spin-spin component only a unified description of all light- and strange-baryon spectra is provided in close agreement with phenomenology. We discuss the extension of the model that includes also the tensor components of the pseudoscalar meson exchange and in addition vector-meson ({rho}, {omega}, K*, {phi}) and scalar-meson ({sigma}) exchanges. A preliminary version thereof provides a description of the baryon spectra with similar good quality.
Date: October 20, 1998
Creator: Wagenbrunn, R. F.
Partner: UNT Libraries Government Documents Department

Two recent results on B physics from CDF

Description: Preliminary results from two recent CDF b physics analyses are presented. The first obtains sin(2{beta})=0.79<sup>+0.41</sup><sub>-0.44</sub> from a measurement of the asymmetry in B<sup>0</sup>, {anti B<sup>0</sup>} {yields} J/{psi}K<sup>0</sup><sub>s</sub> decays, providing the best direct indication so far that CP invariance is violated in the b sector. The second obtains new results on the parity even (A<sub>0</sub> and A<sub>{parallel}</sub>) and odd (A<sub>{perpendicular}</sub>) polarization amplitudes from full angular analyses of B<sup>0</sup> {yields} J/{psi}K*<sup>0</sup> and B<sup>0</sup><sub>s</sub> {yields} J/{psi}{phi} decays: B<sup>0</sup>: {A<sub>0</sub> = 0.770 &plusmn; 0.039 &plusmn; 0.012; A<sub>{parallel}</sub> = (0.530 &plusmn; 0.106 &plusmn; 0.034)e<sup>(2.16 &plusmn; 0.46 &plusmn; 0.10)i</sup>; A<sub>{perpendicular}</sub> = (0.355 &plusmn; 0.156 &plusmn; 0.039)e<sup>(-0.56 &plusmn; 0.53 &plusmn; 0.12)i</sup>}, B<sup>0</sup><sub>s</sub>: {A<sub>0</sub> = 0.778 &plusmn; 0.090 &plusmn; 0.012; A<sub>{parallel}</sub> = (0.407 &plusmn; 0.232 &plusmn; 0.034)e<sup>(1.12 &plusmn; 1.29 &plusmn; 0.11)</sup>i; {vert_bar}A<sub>{perpendicular}</sub> = 0.478 &plusmn; 0.202 &plusmn; 0.040.
Date: June 29, 1999
Creator: Schmidt, M. P.
Partner: UNT Libraries Government Documents Department

Power Corrections in Charmless Nonleptonic B Decays: Annihilationis Factorizable and Real

Description: We classify {Lambda}{sub QCD}/m{sub b} power corrections to nonleptonic B {yields} M{sub 1}M{sub 2} decays, where M{sub 1,2} are charmless non-isosinglet mesons. Using recent developments in soft-collinear effective theory, we prove that the leading contributions to annihilation amplitudes of order {alpha}{sub s}(m{sub b}) {Lambda}{sub QCD}/m{sub b} are real. The leading annihilation amplitudes depend on twist-2 and the twist-3 three parton distributions. A complex nonperturbative parameter from annihilation first appears at {Omega}[{alpha}{sub s}{sup 2}({radical}{Lambda}m{sub b}){Lambda}{sub QCD}/m{sub b}]. 'Chirally enhanced' contributions are also factorizable and real at lowest order. Thus, incalculable strong phases are suppressed in annihilation amplitudes, unless the {alpha}{sub s}({radical}{Lambda}m{sub b}) expansion breaks down. Modeling the distribution functions, we find that (11 {+-} 9)% and (15 {+-} 11)% of the absolute values of the measured {bar B}{sup 0} {yields} K{sup -}{pi}{sup +} and B{sup -} {yields} K{sup -}K{sup 0} penguin amplitudes come from annihilation. This is consistent with the expected size of power corrections.
Date: October 10, 2006
Creator: Arnesen, Christian M.; Ligeti, Zoltan; Rothstein, Ira Z. & Stewart, Iain W.
Partner: UNT Libraries Government Documents Department

Transverse momentum and centrality dependence of high-ptnon-photonic electron suppression in Au+Au collisions at $\sqrt{s_{NN}}$= 200 GeV

Description: The STAR collaboration at RHIC reports measurements of theinclusive yield of non-photonic electrons, which arise dominantly fromsemi-leptonic decays of heavy flavor mesons, over a broad range oftransverse momenta (1.2<pt<10 gevc) in pp, dAu, and AuAucollisions at sqrt sNN = 200 GeV. The non-photonic electron yieldexhibits unexpectedly large suppression in central AuAu collisions athigh pt, suggesting substantial heavy quark energy loss at RHIC. Thecentrality and \pt dependences of the suppression provide constraints ontheoretical models of suppression.
Date: July 11, 2006
Creator: Abelev, B.I.; Adams, J.; Aggarwal, M.M.; Ahammed, Z.; Amonett,J.; Anderson, B.D. et al.
Partner: UNT Libraries Government Documents Department

Observation and Polarization of B->phiK1+ and phiK*2+

Description: With the full BABAR data sample of 465 million B{bar B} pairs, they observe the decays B{sup {+-}} {yields} {psi}K{sub 1}(1270){sup {+-}} and B{sup {+-}} {yields} {psi}K*{sub 2}(1430){sup {+-}}. They measure the branching fractions (6.1 {+-} 1.6 {+-} 1.1) x 10{sup -6} and (8.4 {+-} 1.9 {+-} 0.9) x 10{sup -6} and the fractions of longitudinal polarization 0.46{sub -0.13-0.07}{sup +0.12+0.03} and 0.80{sub -0.10}{sup +0.09} {+-} 0.03, respectively. They also report on the B{sup {+-}} {yields} {psi}K*{sub 0}(1430){sup {+-}} decay branching fraction of (7.0 {+-} 1.3 {+-} 0.9) x 10{sup -6} and several parameters sensitive to CP violation and interference in the above three decays. Upper limits are placed on the B{sup {+-}} decay rates to final states with {psi} and K{sub 1}(1400){sup {+-}}, K*(1410){sup {+-}}, K{sub 2}(1770){sup {+-}}, or K{sub 2}(1820){sup {+-}}. Understanding the observed polarization pattern requires amplitude contributions from an uncertain source.
Date: October 31, 2008
Creator: Aubert, B.; Bona, M.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Prencipe, E. et al.
Partner: UNT Libraries Government Documents Department