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Related papers: Neutral B Meson Mixing in Unquenched Lattice QCD

200 papers

We present a lattice calculation of the B meson B-parameter B_B using the NRQCD action. The heavy quark mass dependence is explicitly studied over a mass range between m_b and 4m_b with the $O(1/m_Q)$ and $O(1/m_Q^2)$ actions. We find that…

High Energy Physics - Lattice · Physics 2009-10-31 S. Hashimoto , K-I. Ishikawa , H. Matsufuru , T. Onogi , N. Yamada

We present updates of our results for neutral $B$-meson mixing and leptonic decay constants obtained in the quenched approximation from a mean-field-improved Sheikholeslami-Wohlert action at two values of lattice spacing. We consider…

High Energy Physics - Phenomenology · Physics 2012-03-23 Laurent Lellouch , C. -J. David Lin

We give a progress report on the calculation of B meson mixing matrix elements, focusing on contributions that could arise beyond the Standard Model. The calculation uses asqtad (light quark) and Fermilab (heavy quark) valence actions and…

High Energy Physics - Lattice · Physics 2011-05-18 C. Bouchard , A. X. El-Khadra , E. D. Freeland , E. Gamiz , A. S. Kronfeld

Calculations of B leptonic decays and B- bar B mixing using NRQCD heavy and Asqtad light valence quarks on the MILC dynamical configurations are described. Smearing has been implemented to substantially reduce the statistical errors of the…

High Energy Physics - Lattice · Physics 2009-11-10 A. Gray , C. Davies , E. Gulez , G. P. Lepage , J. Shigemitsu , M. Wingate

We determine the normalisation of scalar and pseudoscalar current operators made from non-relativistic $b$ quarks and Highly Improved Staggered light quarks in lattice Quantum Chromodynamics (QCD) through $\mathcal{O}(\alpha_s)$ and…

High Energy Physics - Lattice · Physics 2018-03-28 C. Hughes , C. T. H. Davies , C. J. Monahan

We present results of a lattice QCD calculation of $B\to D^*$ and $B_s\to D_s^*$ axial vector matrix elements with both states at rest. These zero recoil matrix elements provide the normalization necessary to infer a value for the CKM…

High Energy Physics - Lattice · Physics 2018-03-14 Judd Harrison , Christine Davies , Matthew Wingate

We give the first accurate results for $B$ and $B_s$ meson masses from lattice QCD including the effect of $u$, $d$ and $s$ sea quarks, and we improve an earlier value for the $B_c$ meson mass. By using the Highly Improved Staggered Quark…

We present our results of lattice calculations of $B$ parameters, which parameterize $\Delta B$=2 transition amplitudes together with the leptonic decay constant. Calculations are made in the quenched approximation at $\beta$=5.7, 5.9, 6.0…

We present results of the first lattice QCD calculations of $B_c \to B_s$ and $B_c \to B_d$ weak matrix elements. Form factors across the entire physical $q^2$ range are then extracted and extrapolated to the physical-continuum limit before…

High Energy Physics - Lattice · Physics 2021-04-08 Laurence J. Cooper , Christine T. H. Davies , Judd Harrison , Javad Komijani , Matthew Wingate

We report on lattice calculations of the $B$ meson decay constant and the B-parameters using the NRQCD action for heavy quark. We performed a set of calculations at three lattice spacings in the quenched approximation in order to…

High Energy Physics - Phenomenology · Physics 2016-11-23 Norikazu Yamada , Shoji Hashimoto

We perform a precise calculation of the mass of the B_c meson using unquenched configurations from the MILC collaboration including 2+1 flavours of improved staggered quarks. Lattice NRQCD and the Fermilab formalism are used to describe the…

High Energy Physics - Lattice · Physics 2011-03-23 I. F. Allison , C. T. H Davies , A. Gray , A. S. Kronfeld , P. B. Mackenzie , J. N. Simone

We report on the status of our lattice-QCD calculation of the hadronic contribution to $B_d^0$ and $B^0_s$ mixing, with 2+1 flavors of dynamical sea quarks. Preliminary results for hadronic mixing matrix elements are given for a basis of…

High Energy Physics - Lattice · Physics 2012-01-10 C. M. Bouchard , E. D. Freeland , C. Bernard , A. X. El-Khadra , E. Gamiz , A. S. Kronfeld , J. Laiho , R. S. Van de Water

In the limit of infinitely heavy b-quarks we compute the SU(3)-breaking ratio xi of neutral B-meson mixing matrix elements. We also present results for the ratio of decay constants f_{B_s}/f_{B_d}. Our calculation employs…

High Energy Physics - Lattice · Physics 2010-11-05 Oliver Witzel

We present results for the matrix elements of the additional $\Delta S=2$ operators that appear in models of physics beyond the Standard Model (BSM), expressed in terms of four BSM $B$-parameters. Combined with experimental results for…

We present the first unquenched lattice-QCD calculation of the form factors for the decay $B\rightarrow D^\ast\ell\nu$ at nonzero recoil. Our analysis includes 15 MILC ensembles with $N_f=2+1$ flavors of asqtad sea quarks, with a strange…

We calculate in three-flavor lattice QCD the short-distance hadronic matrix elements of all five $\Delta C=2$ four-fermion operators that contribute to neutral $D$-meson mixing both in and beyond the Standard Model. We use the MILC…

We present results for the light quark masses and the neutral kaon mixing parameter $B_K$ from lattice QCD. Our data set includes lighter than physical light quark masses and 5 lattice spacings so that chiral extrapolation is not necessary…

High Energy Physics - Phenomenology · Physics 2012-07-02 Christian Hoelbling

We calculate the B-meson decay constants f_B, f_Bs, and their ratio in unquenched lattice QCD using domain-wall light quarks and relativistic b-quarks. We use gauge-field ensembles generated by the RBC and UKQCD collaborations using the…

Accurate measurements of K, D and B meson mixing amplitudes provide stringent constraints in the Unitary Triangle analysis, as well as useful bounds on New Physics scales. Lattice QCD provides a non perturbative tool to compute the hadronic…

High Energy Physics - Lattice · Physics 2014-11-11 Nuria Carrasco

We present a study of leptonic $B$ meson decay constants in lattice QCD with two flavors ($N_f=2$) of light dynamical quarks using NRQCD for the heavy quark. Gauge configurations are generated with a renormalization-group improved gauge…