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We calculate the pressure in QCD with two and three light quarks on a lattice of size 16^3x4 using tree level improved gauge and fermion actions. We argue that for temperatures T > 2T_c systematic effects due to the finite lattice cut-off…

High Energy Physics - Lattice · Physics 2009-10-31 F. Karsch , E. Laermann , A. Peikert

We report on a study of 2+1 flavor lattice QCD with the $O(a)$-improved Wilson quarks on a $16^3\times 32$ lattice at the lattice spacing $1/a\approx 2$GeV employing Luescher's domain-decomposed HMC(LDDHMC) algorithm. This is dedicated to a…

High Energy Physics - Lattice · Physics 2012-08-27 CS Collaboration , Y. Kuramashi , S. Aoki , K. -I. Ishikawa , T. Ishikawa , N. Ishizuka , K. Kanaya , N. Tsutsui , M. Okawa , Y. Taniguchi , A. Ukawa , T. Yoshie

Three-flavor QCD simulation with the $O(a)$-improved Wilson fermion action is made employing an exact fermion algorithm developed for odd number of quark flavors. For the plaquette gauge action, an unexpected first-order phase transition is…

We report on first results of an ongoing effort to simulate lattice QCD with two degenerate flavours of quarks by means of the twisted mass formulation tuned to maximal twist. By utilising recent improvements of the HMC algorithm,…

High Energy Physics - Lattice · Physics 2008-11-26 Karl Jansen , Carsten Urbach , ETM Collaboration

We calculate the form factors for the $B \to D^*\ell\nu_\ell$ decay in 2+1 flavor lattice QCD. For all quark flavors, we employ the M\"obius domain-wall action, which preserves chiral symmetry to a good precision. Our gauge ensembles are…

High Energy Physics - Lattice · Physics 2024-06-05 Y. Aoki , B. Colquhoun , H. Fukaya , S. Hashimoto , T. Kaneko , R. Kellermann , J. Koponen , E. Kou

We review recent results for the chiral behavior of meson masses and decay constants and the determination of the light quark masses by the RBC and UKQCD collaborations. We find that one-loop SU(2) chiral perturbation theory represents the…

High Energy Physics - Lattice · Physics 2010-01-21 Enno E. Scholz

We presents results for the matrix elements of a variety of four-fermion operators calculated using quenched Wilson fermions. Our simulations are done on 170 lattices of size $32^3 x 64$ at $\beta = 6.0$. We find $B_K=0.74 +- 0.04 +- 0.05$,…

High Energy Physics - Lattice · Physics 2008-02-03 Rajan Gupta , Tanmoy Bhattacharya , Stephen Sharpe

We present results for the masses of pseudoscalar mesons in twisted mass lattice QCD with a degenerate doublet of u and d quarks and a non-degenerate doublet of s and c quarks in the framework of next-to-leading order chiral perturbation…

High Energy Physics - Lattice · Physics 2011-05-09 Gernot Münster , Tobias Sudmann

We compute $\Lambda_{\bar{MS}}$ for two flavors of light dynamical quarks using non-perturbatively $O(a)$ improved Wilson fermions. We improve on a recent calculation by employing Pad\'e-improved two-loop and three-loop perturbation theory…

High Energy Physics - Lattice · Physics 2008-11-26 S. Booth , M. Göckeler , R. Horsley , A. C. Irving , B. Joo , S. Pickles , D. Pleiter , P. E. L. Rakow , G. Schierholz , Z. Sroczynski , H. Stüben

Perturbative and non-perturbative results are presented on the renormalization constants of the quark field and the vector, axial-vector, pseudoscalar, scalar and tensor currents. The perturbative computation, carried out at one-loop level…

High Energy Physics - Lattice · Physics 2013-05-30 C. Alexandrou , M. Constantinou , T. Korzec , H. Panagopoulos , F. Stylianou

We present first results from the QCDSF collaboration for the kaon semileptonic decay form factors at zero momentum transfer, using two flavours of non-perturbatively O(a)-improved Wilson quarks. A lattice determination of these form…

High Energy Physics - Lattice · Physics 2008-11-26 QCDSF Collaboration , D. Brommel , R. Horsley , S. M. Morozov , Y. Nakamura , D. Pleiter , G. Schierholz , H. Stuben , J. M. Zanotti

Measurements of the $\Lambda_b \to p \ell^- \bar{\nu}_\ell$ and $\Lambda_b \to \Lambda_c \ell^- \bar{\nu}_\ell$ decay rates can be used to determine the magnitudes of the CKM matrix elements $V_{ub}$ and $V_{cb}$, provided that the relevant…

High Energy Physics - Lattice · Physics 2015-08-05 William Detmold , Christoph Lehner , Stefan Meinel

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

We describe a new set of gauge configurations generated within the CLS effort. These ensembles have N_f=2+1 flavors of non-perturbatively improved Wilson fermions in the sea with the Luescher-Weisz action used for the gluons. Open boundary…

We present an update of HPQCD's lattice QCD determination of the $B_c\to J/\psi$ vector and axial-vector form factors, and provide new results for the tensor form factors. We use the Highly Improved Staggered Quark action for all valence…

High Energy Physics - Lattice · Physics 2025-04-08 Judd Harrison

We present preliminary results at {\beta} = 1.95 (a = 0.077 fm) on the first unquenched N_f=2+1+1 lattice computation of the B_K parameter which controls the neutral kaon oscillations in the Standard Model. Using N_f=2+1+1 maximally twisted…

High Energy Physics - Lattice · Physics 2011-11-08 N. Carrasco , V. Gimenez , P. Dimopoulos , R. Frezzotti , D. Palao , G. C. Rossi , V. Lubicz , M. Papinutto , F. Sanfilippo , S. Simula

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…

We calculate---for the first time in three-flavor lattice QCD---the hadronic matrix elements of all five local operators that contribute to neutral $B^0$- and $B_s$-meson mixing in and beyond the Standard Model. We present a complete error…

We present a preliminary lattice determination of the masses and decay constants of the pseudoscalar and vector mesons $B_c$ and $B_c^*$. Our analysis is based on the gauge configurations produced by the European Twisted Mass Collaboration…

High Energy Physics - Lattice · Physics 2018-12-04 D. Becirevic , A. Melis , L. Riggio , G. Salerno , S. Simula

We calculate the $B \to\pi\ell\nu$ and $B_s \to K \ell\nu$ form factors in dynamical lattice QCD. We use the (2+1)-flavor RBC-UKQCD gauge-field ensembles generated with the domain-wall fermion and Iwasaki gauge actions. For the $b$ quarks…

High Energy Physics - Lattice · Physics 2015-04-28 J. M. Flynn , T. Izubuchi , T. Kawanai , C. Lehner , A. Soni , R. S. Van de Water , O. Witzel