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Related papers: Update on $f_B$

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The semileptonic process, B --> \pi l \nu, is studied via full QCD Lattice simulations. We use unquenched gauge configurations generated by the MILC collaboration. These include the effect of vacuum polarization from three quark flavors:…

High Energy Physics - Lattice · Physics 2014-11-17 Emel Gulez , Alan Gray , Matthew Wingate , Christine T. H. Davies , G. Peter Lepage , Junko Shigemitsu

We present the latest preliminary results of the MILC collaboration's analysis of the light pseudoscalar meson sector. The analysis includes data from new ensembles with smaller lattice spacings, smaller light quark masses and…

Several quantities relevant to phenomenological studies of the mixing of neutral B mesons are computed on the lattice. Our main results are: f_{Bd} sqrt(B_{Bd})=206(28)(7) MeV, f_{Bs} sqrt(B_{Bs})/f_{Bd}sqrt(B_{Bd})=1.16(7). We also obtain…

High Energy Physics - Lattice · Physics 2009-10-31 D. Becirevic , D. Meloni , A. Retico , V. Gimenez , L. Giusti , V. Lubicz , G. Martinelli

We present the results for $B_K$ calculated using HYP-smeared staggered fermions using lattices generated by the MILC collaboration using the asqtad staggered action. We have done the calculation on 8 ensembles of these lattices, including…

High Energy Physics - Lattice · Physics 2010-02-23 Taegil Bae , Hyung-Jin Kim , Jangho Kim , Jongjeong Kim , Kwangwoo Kim , Boram Yoon , Weonjong Lee , Chulwoo Jung , Stephen R. Sharpe

This talk summarizes the quenched calculation of $f_B$ and $f_{B_s}$ presented in hep-lat/9801038. The heavy quark is simulated using an $O(1/M^2)$ improved NRQCD action, and the tadpole improved clover action is used for the light quarks.…

High Energy Physics - Lattice · Physics 2007-05-23 Tanmoy Bhattacharya

We report on the ALPHA Collaboration's lattice B-physics programme based on N_f=2 O(a) improved Wilson fermions and HQET, including all NLO effects in the inverse heavy quark mass, as well as non-perturbative renormalization and matching,…

Measurement of the B_s oscillation frequency via B_s mixing analyses provides a powerful constraint on the CKM matrix elements. The study of B_d oscillations is an important step towards B_s mixing and a preliminary measurement of Delta m_d…

High Energy Physics - Experiment · Physics 2010-04-22 Tulika Bose

I give a brief overview of the status of lattice QCD, concentrating on topics relevant to phenomenology. I discuss the calculation of the light quark spectrum, the lattice prediction of $\alpha_\MS(M_Z)$, and the calculation of $f_B$.

High Energy Physics - Phenomenology · Physics 2007-05-23 Stephen Sharpe

Recent results from BaBar and Belle experiments on $B \bar B$ mixing and $\sin 2\phi_1$ are presented. Accuracy of $\Delta m_d$ measurements has reached 1.2%. Higher order effects within the Standard Model or possible new physics effect…

High Energy Physics - Experiment · Physics 2010-11-23 Kazuo Abe

We report the final results of the ALPHA collaboration for some B-physics observables: $f_B$, $f_{B_s}$ and $m_b$. We employ CLS configurations with 2 flavors of $O(a)$ improved Wilson fermions in the sea and pion masses ranging down to 190…

High Energy Physics - Lattice · Physics 2013-09-05 F. Bernardoni , B. Blossier , J. Bulava , M. Della Morte , P. Fritzsch , N. Garron , A. Gerardin , J. Heitger , G. von Hippel , H. Simma , R. Sommer

We update the Standard-Model predictions for several quantities related to $B_s - \bar B_s$ and $B_d - \bar B_d$ mixing. The mass and width differences in the $B_s$ system read $ \Delta M_s^{\rm SM} = (17.3 \pm 2.6) ps^{-1}$ and $\Delta…

High Energy Physics - Phenomenology · Physics 2011-11-10 Alexander Lenz , Ulrich Nierste

We present an update on our calculation of the short-distance $D^0$-meson mixing hadronic matrix elements. The analysis is performed on the MILC collaboration's $N_f=2+1$ asqtad configurations. We use asqtad light valence quarks and the…

High Energy Physics - Lattice · Physics 2014-12-16 C. C. Chang , C. Bernard , C. M. Bouchard , A. X. El-Khadra , E. D. Freeland , E. Gámiz , A. S. Kronfeld , J. Laiho , R. S. Van de Water

Anticipating future precise measurements of the D- and B-like (semi-)leptonic and hadronic decays for alternative determinations of the CKM mixing angles, we pursue our program on the D- and B-like mesons by improving the estimates of…

High Energy Physics - Phenomenology · Physics 2015-06-02 Stephan Narison

We compute next-to-next-to-leading order perturbative corrections to the decay width difference of mass eigenstates and the charge-parity asymmetry $a_{\rm fs}$ in flavour-specific decays of neutral $B$ mesons. In our calculation we take…

High Energy Physics - Phenomenology · Physics 2025-05-30 Marvin Gerlach , Ulrich Nierste , Pascal Reeck , Vladyslav Shtabovenko , Matthias Steinhauser

We present a new determination of the B and B_s meson decay constants using NRQCD b-quarks, HISQ light and strange valence quarks and the MILC collaboration N_f=2+1 lattices. The new calculations improve on HPQCD's earlier work with NRQCD…

High Energy Physics - Lattice · Physics 2012-08-27 Heechang Na , Chris J. Monahan , Christine T. H. Davies , Ron Horgan , G. Peter Lepage , Junko Shigemitsu

An analysis of the CKM matrix parameters within the {\it R}fit approach is presented using updated input values with special emphasis on the recent $\sin{2\beta}$ measurements from BABAR and Belle. The QCD Factorisation Approach describing…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. Höcker , H. Lacker , S. Laplace , F. Le Diberder

We extend our earlier lattice-QCD analysis of heavy-quark correlators to smaller lattice spacings and larger masses to obtain new values for the c mass and QCD coupling, and, for the first time, values for the b mass:…

High Energy Physics - Lattice · Physics 2014-11-20 C. McNeile , C. T. H. Davies , E. Follana , K. Hornbostel , G. P. Lepage

The current report covers the period from the second half of 2011 to late 2014. It is divided into three areas covering rotational, vibrational, and electronic spectroscopy. A signifcant amount of experimental and theoretical work has been…

Atomic Physics · Physics 2015-10-30 Steven R. Federman , Peter F. Bernath , Holger S. P. Mueller

The current status of the lattice-QCD calculations of the form factors of the $B\to D^\ast\ell\nu$ semileptonic decay is reviewed. Particular emphasis is given to the most mature calculation at non-zero recoil coming from the Fermilab…

High Energy Physics - Lattice · Physics 2019-06-11 A. Vaquero , C. DeTar , A. X. El-Khadra , A. S. Kronfeld , J. Laiho , R. S. Van de Water

We study $B_d$ and $B_s$ mixing in unquenched lattice QCD employing the MILC collaboration gauge configurations that include u, d, and s sea quarks based on the improved staggered quark (AsqTad) action and a highly improved gluon action. We…

High Energy Physics - Lattice · Physics 2009-09-30 Elvira Gámiz , Christine T. H. Davies , G. Peter Lepage , Junko Shigemitsu , Matthew Wingate