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We present the first unquenched lattice-QCD calculation of the form factors for the decay B -> D*t nu at nonzero recoil. Our analysis includes 15 MILC ensembles with N-f = 2 + 1 flavors of asqtad sea quarks, with a strange quark mass close to its physical mass. The lattice spacings range from a asymptotic to 0.15 fm down to 0.045 fm, while the ratio between the light-and the strange-quark masses ranges from 0.05 to 0.4. The valence b and c quarks are treated using the Wilson-clover action with the Fermilab interpretation, whereas the light sector employs asqtad staggered fermions. We extrapolate our results to the physical point in the continuum limit using rooted staggered heavy-light meson chiral perturbation theory. Then we apply a model independent parametrization to extend the form factors to the full kinematic range. With this parametrization we perform a joint lattice-QCD/experiment fit using several experimental datasets to determine the CKM matrix element |V-cb|. We obtain |V-cb| = (38.40 +/- 0.68(th) +/- 0.34(exp) +/- 0.18(EM)) x 10(-3). The first error is theoretical, the second comes from experiment and the last one includes electromagnetic and electroweak uncertainties, with an overall chi(2)/dof = 126/84, which illustrates the tensions between the experimental data sets, and between theory and experiment. This result is in agreement with previous exclusive determinations, but the tension with the inclusive determination remains. Finally, we integrate the differential decay rate obtained solely from lattice data to predict R(D*) = 0.265 +/- 0.013, which confirms the current tension between theory and experiment., United States Department of Energy (DOE), National Science Foundation's Teragrid/XSEDE Program, United States Department of Energy (DOE) DE-FG02-13ER41976 DE-SC0009998 DE-SC0010120 DE-SC0015655, National Science Foundation (NSF) PHY17-19626 PHY14-17805 SRA (Spain) P18-FR-4314, Consejeria de Economia, Innovacion, Ciencia y Empleo, Junta de Andalucia (Spain) P18-FR-4314 A-FQM-467-UGR18, Fermilab Distinguished Scholars Program

We present preliminary blinded results from our analysis of the form factors for $B\to D^\ast\ell\nu$ decay at non-zero recoil. Our analysis includes 15 MILC asqtad ensembles with $N_f=2+1$ flavors of sea quarks and lattice spacings ranging from $a\approx 0.15$ fm down to $0.045$ fm. The valence light quarks employ the asqtad action, whereas the $b$ and $c$ quarks are treated using the Fermilab action. We discuss the impact that our results will have on $\left|V_{cb}\right|$ and $R(D\ast)$.

We introduce a new method for calculating the ${\rm O}(\alpha^3)$ hadronic-vacuum-polarization contribution to the muon anomalous magnetic moment from ${ab-initio}$ lattice QCD. We first derive expressions suitable for computing the higher-order contributions either from the renormalized vacuum polarization function $\hat\Pi(q^2)$, or directly from the lattice vector-current correlator in Euclidean space. We then demonstrate the approach using previously-published results for the Taylor coefficients of $\hat\Pi(q^2)$ that were obtained on four-flavor QCD gauge-field configurations with physical light-quark masses. We obtain $10^{10} a_\mu^{\rm HVP,HO} = -9.3(1.3)$, in agreement with, but with a larger uncertainty than, determinations from $e^+e^- \to {\rm hadrons}$ data plus dispersion relations., Comment: Expanded and clarified discussion and revised Figure 4. Results unchanged. 11 pages, 5 tables, 5 figures. Version accepted to Physical Review D

We present high-precision results from lattice QCD for the mass splittings of the low-lying charmonium states. For the valence charm quark, the calculation uses Wilson-clover quarks in the Fermilab interpretation. The gauge-field ensembles are generated in the presence of up, down, and strange sea quarks, based on the improved staggered (asqtad) action, and gluon fields, based on the one-loop, tadpole-improved gauge action. We use five lattice spacings and two values of the light sea quark mass to extrapolate the results to the physical point. An enlarged set of interpolating operators is used for a variational analysis to improve the determination of the energies of the ground states in each channel. We present and implement a continuum extrapolation within the Fermilab interpretation, based on power-counting arguments, and thoroughly discuss all sources of systematic uncertainty. We compare our results for various mass splittings with their experimental values, namely, the 1S hyperfine splitting, the 1P-1S splitting and the P-wave spin-orbit and tensor splittings. Given the uncertainty related to the width of the resonances, we find excellent agreement., Comment: 24 pages, 8 figures

We thank Jochen Dingfelder for the helpful information about the experimental measurements and HFAG averaging procedure. D.D. thanks Peter Lepage for sharing his lsqfit code (github.com/gplepage/lsqfit), which is extensively used in the fitting procedures of the analysis. We also thank Heechang Na for valuable discussions. Computations for this work were carried out with resources provided by the USQCD Collaboration, the Argonne Leadership Computing Facility, the National Energy Research Scientific Computing Center, and the Los Alamos National Laboratory, which are funded by the Office of Science of the United States Department of Energy; and with resources provided by the National Institute for Computational Science, the Pittsburgh Supercomputer Center, the San Diego Supercomputer Center, and the Texas Advanced Computing Center, which are funded through the National Science Foundation's Teragrid/XSEDE Program. This work was supported in part by the U.S. Department of Energy under Grants No. DE-FG02-91ER40628 (C.B., J.K.), No. DE-FC02-12ER41879 (C.D., J.F., L.L.), No. DE-SC0010120 (S.G.), No. DE-FG02-91ER40661 (S.G., R.Z.), No. DE-FC02-06ER41443 (R.Z.), No. DE-FG02-13ER42001 (D.D., A.X.K.), No. DE-FG02-13ER41976 (D.T.), No. DE-SC0010114 (Y.M.); by the National Science Foundation under Grants No. PHY-1067881, No. PHY-10034278 (C.D., L.L., S.-W.Q.), No. PHY-1417805 (J.L., D.D.), No. PHY1212389 (R.Z.), No. PHY-1316748 (R.S.); by the URA Visiting Scholars' program (C.M.B., D.D., A.X.K., Y.L., Y.M.); by the MINECO (Spain) under Grants No. FPA2010-16696, No. FPA2006-05294, and the Ramon y Cajal program (E.G.); by the Junta de Andalucia (Spain) under Grants No. FQM-101 and No. FQM-6552 (E.G.); by the European Commission under Grant No. PCIG10-GA-2011-303781 (E.G.); by the German Excellence Initiative and the European Union Seventh Framework Programme under grant agreement No. 291763 as well as the European Union's Marie Curie COFUND program (A.S.K.); and by the Basic Science Research Program of the National Research Foundation of Korea (NRF) funded by the Ministry of Education (No. 2014027937) and the Creative Research Initiatives Program (No. 2014001852) of the NRF grant funded by the Korean government (MEST) (J.A.B.). This manuscript has been coauthored by an employee of Brookhaven Science Associates, LLC, under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy. Fermilab is operated by Fermi Research Alliance, LLC, under Contract No. DE-AC02-07CH11359 with the U.S. Department of Energy., We present a lattice-QCD calculation of the B→πℓν semileptonic form factors and a new determination of the CKM matrix element |Vub|. We use the MILC asqtad (2+1)-flavor lattice configurations at four lattice spacings and light-quark masses down to 1/20 of the physical strange-quark mass. We extrapolate the lattice form factors to the continuum using staggered chiral perturbation theory in the hard-pion and SU(2) limits. We employ a model-independent z parametrization to extrapolate our lattice form factors from large-recoil momentum to the full kinematic range. We introduce a new functional method to propagate information from the chiral-continuum extrapolation to the z expansion. We present our results together with a complete systematic error budget, including a covariance matrix to enable the combination of our form factors with other lattice-QCD and experimental results. To obtain |Vub|, we simultaneously fit the experimental data for the B→πℓν differential decay rate obtained by the BABAR and Belle collaborations together with our lattice form-factor results. We find |Vub|=(3.72±0.16)×10−3, where the error is from the combined fit to lattice plus experiments and includes all sources of uncertainty. Our form-factor results bring the QCD error on |Vub| to the same level as the experimental error. We also provide results for the B→πℓν vector and scalar form factors obtained from the combined lattice and experiment fit, which are more precisely determined than from our lattice-QCD calculation alone. These results can be used in other phenomenological applications and to test other approaches to QCD., National Institute for Computational Science, Pittsburgh Supercomputer Center, San Diego Supercomputer Center, Texas Advanced Computing Center, National Science Foundation's Teragrid/XSEDE Program, United States Department of Energy (DOE) DE-FG02-91ER40628 DE-FC02-12ER41879 DE-SC0010120 DE-FG02-91ER40661 DE-FC02-06ER41443 DE-FG02-13ER42001 DE-FG02-13ER41976 DE-SC0010114 DE-AC02-98CH10886 DE-AC02-07CH11359, National Science Foundation (NSF) PHY-1067881 PHY-10034278 PHY-1417805 PHY1212389 PHY-1316748, URA Visiting Scholars' program, MINECO (Spain) FPA2010-16696 FPA2006-05294, Spanish Government, Junta de Andalucia FQM-101 FQM-6552, European Commission Joint Research Centre PCIG10-GA-2011-303781, German Excellence Initiative, European Union (EU) 291763, European Union (EU), Basic Science Research Program of the National Research Foundation of Korea (NRF), Ministry of Education 2014027937, Creative Research Initiatives Program of the NRF grant - Korean government (MEST) 2014001852

We use lattice QCD to calculate the B-mixing hadronic matrix elements for a basis of effective four-quark operators that spans the space of all possible contributions in, and beyond, the Standard Model. We present results for the SU(3)-breaking ratio and discuss our ongoing calculation of the mixing matrix elements, including the first calculation of the beyond the Standard Model matrix elements from unquenched lattice QCD., 3 pages, 1 figure. Proceedings for CIPANP 2012 - Eleventh Conference on the Intersections of Particle and Nuclear Physics, St. Petersburg FL, May 29 - June 3 2012