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Related papers: Matrix Elements of Four-quark Operators Relevant t…

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We calculate the bag parameters for neutral $B$-meson mixing in and beyond the Standard Model, in full four-flavour lattice QCD for the first time. We work on gluon field configurations that include the effect of $u$, $d$, $s$ and $c$ sea…

High Energy Physics - Lattice · Physics 2019-12-04 R. J. Dowdall , C. T. H. Davies , R. R. Horgan , G. P. Lepage , C. J. Monahan , J. Shigemitsu , M. Wingate

In this talk we review the theoretical status of the lifetime ratios of heavy hadrons and of the B-mixing quantities $\Delta M_s$, $\Delta \Gamma_s$ and $\phi_s$. While $\Delta M_s$ and $\Delta \Gamma_s$ suffer from large uncertainties due…

High Energy Physics - Phenomenology · Physics 2008-11-26 Alexander Lenz

We evaluate two-loop b -> s gamma matrix elements of all the four-quark operators containing no derivatives. Contrary to previous calculations, no expansion in the mass ratio mc/mb is performed, and all the possible Dirac and flavor…

High Energy Physics - Phenomenology · Physics 2009-11-07 Andrzej J. Buras , Andrzej Czarnecki , Mikolaj Misiak , Joerg Urban

We introduce a new parameterization of four-fermion matrix elements which does not involve quark masses and thus allows a reduction of systematic uncertainties in physical amplitudes. As a result the apparent quadratic dependence of e'/e on…

High Energy Physics - Phenomenology · Physics 2009-10-31 L. Giusti

We propose the formulation of lattice QCD wherein all elements of the theory (gauge action, fermionic action, theta-term, and all operators) are constructed from a single object, namely the lattice Dirac operator D with exact chiral…

High Energy Physics - Lattice · Physics 2007-05-23 Ivan Horvath

Renormalization factors for $\Delta S =1$ four-quark operators in the effective weak Hamiltonian are perturbatively evaluated in domain-wall QCD. The one-loop corrections of $\Delta S=1$ four-quark operators consist of two types of…

High Energy Physics - Lattice · Physics 2009-10-31 Sinya Aoki , Yoshinobu Kuramashi

Lattice Quantum Chromodynamics (QCD) has significantly contributed to our understanding of the CKM matrix through precise determinations of hadronic matrix elements. With advancements in theoretical methodologies and computational…

High Energy Physics - Lattice · Physics 2024-03-29 Luka Leskovec , Stefan Meinel , Marcus Petschlies , John Negele , Srijit Paul , Andrew Pochinsky , Gumaro Rendon

We review the application of lattice QCD to the phenomenology of b- and c-quarks. After a short discussion of the lattice techniques used to evaluate hadronic matrix elements and the corresponding systematic uncertainties, we summarise…

High Energy Physics - Lattice · Physics 2016-11-03 J. M. Flynn , C. T. Sachrajda

We use lattice QCD simulations, with MILC configurations (including vacuum polarization from u, d, and s quarks), to update our previous determinations of the QCD coupling constant. Our new analysis uses results from 6 different lattice…

High Energy Physics - Lattice · Physics 2009-01-08 C. T. H. Davies , K. Hornbostel , I. D. Kendall , G. P. Lepage , C. McNeile , J. Shigemitsu , H. Trottier

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 an update of our NRQCD calculation of $B_B$ at $\beta$=5.9 with increased statistics. We also discuss a calculation of $B_S$, which is relevant to the width difference in the $B_s-\bar{B}_s$ mixing.

High Energy Physics - Lattice · Physics 2015-06-25 N. Yamada , S. Hashimoto , K-I. Ishikawa , H. Matsufuru , T. Onogi

Recent results relevant for the B-physics phenomenology, obtained from lattice QCD simulations by the APE Collaboration, are reviewed. This includes the B0-B0bar mixing amplitude, B-> pi semileptonic decay and the relative width difference…

High Energy Physics - Lattice · Physics 2009-10-31 Damir Becirevic

We have used domain wall fermions to calculate $K \to \pi$ and $K \to 0$ matrix elements which can be used to study the $\Delta I = 1/2$ rule for K decays in the Standard Model. Nonlinearities in the $\Delta I = 3/2$ matrix elements due to…

High Energy Physics - Lattice · Physics 2007-05-23 Calin R. Cristian , RBC Collaboration

We present one-loop matching coefficients between continuum and lattice QCD for the heavy-light four-fermion operators relevant for neutral B meson mixing both within and beyond the Standard Model. For the lattice theory we use…

High Energy Physics - Lattice · Physics 2008-11-26 Elvira Gamiz , Junko Shigemitsu , Howard Trottier

We propose a non-perturbative method to determine the mixing coefficients of $\Delta s=2$ four-quark operators for the Wilson quark action using chiral Ward identities. The method is applied to calculate B_K in quenched QCD.

High Energy Physics - Lattice · Physics 2009-10-28 JLQCD Collaboration , S. Aoki , M. Fukugita , S. Hashimoto , N. Ishizuka , Y. Iwasaki , K. Kanaya , Y. Kuramashi , H. Mino , M. Okawa , A. Ukawa , T. Yoshie

We calculate the leading-order matrix element for the decay $B \to K^* \gamma$ in the quenched approximation of lattice QCD on a $24^3 \times 48$ lattice at $\beta=6.2$, using an O(a)-improved fermion action. Extrapolating the quark masses…

High Energy Physics - Lattice · Physics 2015-06-25 UKQCD Collaboration

We present some preliminary results for $B_K$ at $\beta=6.0$, using the twisted mass QCD formalism for the computation of bare matrix elements of the $\Delta S=2$ operator. The main advantage of the method is that mixing with other $d=6$…

High Energy Physics - Lattice · Physics 2009-11-10 P. Dimopoulos , J. Heitger , C. Pena , S. Sint , A. Vladikas

Neutral $B$ meson mixing matrix elements and $B$ meson decay constants are calculated. Static approximation is used for $b$ quark and domain-wall fermion formalism is employed for light quarks. The calculations are carried out on $2+1$…

High Energy Physics - Lattice · Physics 2015-06-30 Yasumichi Aoki , Tomomi Ishikawa , Taku Izubuchi , Christoph Lehner , Amarjit Soni

We investigate the mass differences $\Delta M_{B_{d,s}}$ in the mixing $B^0_{d,s}-\bar B^0_{d,s}$ with a new up-like quark $t^{\prime}$ in the sequential fourth generation model. We give the basic formulae for $\Delta M_{B_{d,s}}$ in this…

High Energy Physics - Phenomenology · Physics 2008-11-26 Wu-Jun Huo

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…