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Estimated Errors in |Vcd|/|Vcs| from semileptonic D decays

Description: We estimate statistical and systematic errors in the extraction of the CKM ratio {vert_bar}V{sub cd}{vert_bar}/{vert_bar}v{sub cs}{vert_bar} from exclusive D-meson semileptonic decays using lattice QCD and anticipated new experimental results.
Date: November 1, 1998
Creator: J.N.Simone, A.X.El-Khadra, S.Hashimoto, A.S.Kronfeld, P.B.Mackenzie, and S.M.Ryan
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Partner: UNT Libraries Government Documents Department
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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
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Partner: UNT Libraries Government Documents Department
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Photoproduction of charm pairs

Description: A large sample of events containing fully and partially reconstructed pairs of charmed D mesons has been studied by the Fermilab photoproduction experiment FOCUS (FNAL-E831). Correlations between photoproduced D and {bar D} mesons are used to study heavy quark production dynamics. Correlation results are presented for fully and partially reconstructed pairs of charmed D mesons. The results are compared to Monte Carlo predictions based on a recent version of PYTHIA with default settings.
Date: September 2, 2003
Creator: Gottschalk, Erik E
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Partner: UNT Libraries Government Documents Department
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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, Harry J.
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Partner: UNT Libraries Government Documents Department
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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.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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D-meson enhancement in pp collisions at the LHC due to nonlinear gluon evolution

Description: When nonlinear effects on the gluon evolution are included with constraints from HERA, the gluon distribution in the free proton is enhanced at low momentum fractions, x {approx}< 0.01, and low scales, Q{sup 2} {approx}< 10 GeV{sup 2}, relative to standard, DGLAP-evolved, gluon distributions. Consequently, such gluon distributions can enhance charm production in pp collisions at center of mass energy 14 TeV by up to a factor of five at midrapidity, y {approx} 0, and transverse momentum p{… more
Date: August 22, 2004
Creator: Dainese, A.; Vogt, R.; Bondila, M.; Eskola, K.J. & Kolhinen, V.J.
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Partner: UNT Libraries Government Documents Department
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Time Dependent B{sub s}{sup 0}-{bar B}{sub s}{sup 0} Mixing Using Inclusive and Semileptonic B Decays at SLD

Description: We set a preliminary 95% C.L. exclusion on the oscillation frequency of B{sub s}{sup 0}-{bar B}{sub s}{sup 0} mixing using a sample of 350,000 hadronic Z{sup 0} decays collected by the SLD experiment at the SLC during the 1997-98 run. The analyses determine the b-hadron flavor at production by exploiting the large forward-backward asymmetry of polarized Z{sup 0} {yields} b{bar b} decays as well as information from the hemisphere opposite that of the reconstructed B decay. In one analysis, B dec… more
Date: September 14, 1999
Creator: Willocq, Stephane
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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D meson hadronic decays at CLEO-c

Description: The recent CLEO-c results on hadronic decays of D and D{sub s} mesons are presented. First the absolute branching fractions for D and D{sub s} mesons using a double tag technique are discussed, then are the Cabibbo suppressed decays and doubly Cabibbo suppressed decays. Finally, I present the inclusive and rare decay modes and other measurements from CLEO-c. These decays illuminate a wide range of physics. A brief theoretical introduction is given before the corresponding discussion on measurem… more
Date: January 1, 2011
Creator: Yang, Fan
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Partner: UNT Libraries Government Documents Department
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Production asymmetries in x{sub f} and P{sub t}{sup 2} for D{sup {plus_minus}} mesons

Description: We present differences in leading and non-leading charged D meson production as a doubly-differential function of both P{sup 2}{sub t} and {chi}{integral}. Comparisons to specific models are made. This information is from the analysis of half the data from Fermilab experiment E791, taken during the 1991-2 fixed target run with a 500 GeV/c {pi}{sup {minus}} beam incident on a segmented target.
Date: November 1, 1994
Creator: Carter, T. & Collaboration, E791
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Partner: UNT Libraries Government Documents Department
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Rare Decays And Exotic States With BaBar

Description: Results from the BABAR experiment are presented for searches for several rare FCNC B and D meson decays, including the modes B{sup 0} {yields} {ell}{sup +}{ell}{sup -} and D{sup 0} {yields} {ell}{sup +}{ell}{sup -}, B {yields} ({rho},{omega}){gamma} and B{sup +} {yields} (K,{pi}){sup +}{nu}{bar {nu}}. Limits on lepton flavor violation in neutrino-less {tau} decays are also discussed. Finally, results of BABAR searches for the strange pentaquark states {Theta}{sup +}(1540), {Xi}{sup --}(1860) an… more
Date: August 28, 2006
Creator: Robertson, S. H.
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Partner: UNT Libraries Government Documents Department
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Search for flavor-changing-neutral-current D meson decays

Description: We study the flavor-changing-neutral-current process c {yields} u{mu}{sup +}{mu}{sup -} using 1.3 fb{sup -1} of p{bar p} collisions at {radical}s = 1.96 TeV recorded by the D0 detector operating at the Fermilab Tevatron Collider. We see clear indications of the D{sup +}{sub s} and D{sup +} {yields} {phi}{pi}{sup +} {yields} {mu}{sup +}{mu}{sup -}{pi}{sup +} final states with significance greater than four standard deviations above background for the D{sup +} state. We search for the continuum d… more
Date: August 1, 2007
Creator: Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
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Partner: UNT Libraries Government Documents Department
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Searching for new physics with charm

Description: The author considers the prospect of using the charm system as a laboratory for probing new physics. The theoretical expectations for rare charm meson decays, D{sup 0} - {bar D}{sup 0}, and charm quark asymmetries in Z decays are examined in the Standard Model. The effects of new physics from several classes of nonstandard dynamical models are summarized for these phenomena.
Date: June 1995
Creator: Hewett, J. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Three electroweak results from lattice QCD

Description: Quantum chromodynamics is needed to understand quarks and, hence, to determine the quarks` Yukawa couplings from experimental measurements. As a short illustration, the results of three lattice calculations are given.
Date: August 1, 1998
Creator: Kronfeld, A.S., FERMI
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Partner: UNT Libraries Government Documents Department
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Measurement of the B{sup +} and B{sup 0} lifetimes at CDF

Description: Two measurements of the lifetime of neutral and charged B mesons in p{bar p} collisions at {radical}s = 1.8 TeV by the CDF experiment are presented. The first relies on the study of exclusive decays of the type B {yields} {psi} K, the second on semileptonic decays of a B meson into a D{degrees} or a D. The combined results are {tau}(B{sup +}) = 1.62 {+-} 0.09 ps, {tau}(B{sub 0}) = 1.60 {+-} 0.09 ps and {tau}(B{sup +})/{tau}(B{sup 0}) = 1.00 {+-} 0.07.
Date: October 1, 1995
Creator: Bortoletto, D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Measurement of CP violation observables and parameters for the decays $B^{\pm}\to DK^{*\pm}$

Description: We study the decay B{sup -} {yields} DK*{sup -} using a sample of 379 x 10{sup 6} {Upsilon}(4S) {yields} B{bar B} events collected with the BABAR detector at the PEP-II B-factory. We perform a 'GLW' analysis where the D meson decays into either a CP-even (CP+) eigenstate (K{sup +}K{sup -}, {pi}{sup +}{pi}{sup -}), CP-odd (CP-) eigenstate (K{sub S}{sup 0}{pi}{sup 0}, K{sub S}{sup 0}{phi}, K{sub S}{sup 0}{omega}) or a non-CP state (K{sup -}{pi}{sup +}). We also analyze D meson decays into K{sup +… more
Date: August 26, 2010
Creator: Aubert, Bernard; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E.; Prudent, X. et al.
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Partner: UNT Libraries Government Documents Department
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Improved Measurement of the CKM Angle gamma in B^-+ to D^(*) K^(*)-+Decays with a Dalitz Plot Analysis of D Decays to K_S^0 pi+ pi- and K_S^0 K+ K-

Description: We report on an improved measurement of the Cabibbo-Kobayashi-Maskawa CP-violating phase {gamma} through a Dalitz plot analysis of neutral D meson decays to K{sub s}{sup 0}{pi}{sup +}{pi}{sup -} and K{sub s}{sup 0}K{sup +}K{sup -} produced in the processes B{sup {-+}} {yields} DK{sup {-+}}, B{sup {-+}} {yields} D* K{sup {-+}} with D* {yields} D{pi}{sup 0}, D{gamma}, and B{sup {-+}} {yields} DK*{sup {-+}} with K8{sup {-+}} {yields} K{sub S}{sup 0}{pi}{sup {-+}}. Using a sample of 383 million B{b… more
Date: April 22, 2008
Creator: Aubert, B.
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Partner: UNT Libraries Government Documents Department
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D0 - Anti-D0 Mixing at BaBar

Description: The BABAR and Belle collaborations have recently found evidence for mixing within the D meson system. We present some of the mixing search techniques used by BABAR and their status as of the beginning of the summer 2007. These have culminated in a measurement in the K{pi} decay final state of the D that is inconsistent with the no-mixing hypothesis with a significance of 3.9 standard deviations.
Date: October 23, 2007
Creator: Seiden, A. & /UC, Santa Cruz
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Partner: UNT Libraries Government Documents Department
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Measurement of the Branching Fraction and Decay Rate Asymmetry of B to D_pi+ pi- pi0 K-

Description: The authors report the observation of the decay B{sup -} {yields} D{sub {pi}{sup +}{pi}{sup -}{pi}{sup 0}}K{sup -}, where D{sub {pi}{sup +}{pi}{sup -}{pi}{sup 0}} indicates a neutral D meson detected in the final state {pi}{sup +}{pi}{sup -}{pi}{sup 0}, excluding K{sub S}{sup 0}{pi}{sup 0}. This doubly Cabibbo-suppressed decay chain can be used to measure the CKM phase {gamma}. Using about 229 million e{sup +}e{sup -} {yields} B{bar B} events recorded by the BABAR experiment at the PEP-II e{sup… more
Date: June 10, 2005
Creator: Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.
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Partner: UNT Libraries Government Documents Department
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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 {… more
Date: January 26, 2000
Creator: Simone, J. N.; Hashimoto, S.; El-Khadra, A. X.; Kronfeld, A. S.; Mackenzie, P. B. & Ryan, S. M.
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Partner: UNT Libraries Government Documents Department
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Search for new mechanism of CP violation through tau decay and semileptonic decay at hadrons

Description: If CP is violated in any decay process involving leptons it will signify the existence of a new force (called the X boson) responsible for CP violation that may be the key to understanding matter-antimatter asymmetry in the universe. The author discusses the signatures of CP violation in (1) the decay of tau lepton, and (2) the semileptonic decay of {pi}, K, D, B and t particles by measuring the polarization of the charged lepton in the decay. The author discusses how the coupling constants and… more
Date: November 1, 1996
Creator: Tsai, Yung Su
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Partner: UNT Libraries Government Documents Department
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