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Related papers: B-parameters for DeltaS = 2 Supersymmetric Operato…

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We calculate the non-forward quark matrix elements of operators with two covariant derivatives needed for the renormalisation of the second moment of generalised parton distributions in one-loop lattice perturbation theory using Wilson…

High Energy Physics - Lattice · Physics 2008-11-26 M. Göckeler , R. Horsley , H. Perlt , P. E. L. Rakow , A. Schäfer , G. Schierholz , A. Schiller

We determine the chiral corrections to the matrix elements of the Delta B=0 four-quark operators which are relevant to the studies of the ratios of lifetimes of heavy-light mesons as well as to the power corrections to the inclusive…

High Energy Physics - Phenomenology · Physics 2009-01-16 Damir Becirevic , Svjetlana Fajfer , Jernej F. Kamenik

We present the status of a lattice calculation for the K-->pipi matrix elements of the (delta S=1) effective weak Hamiltonian, directly with two pion in the final state. We study the energy shift of two pion in a finite volume both in the…

High Energy Physics - Lattice · Physics 2012-08-27 Ph. Boucaud , V. Gimenez , C. J. D. Lin , V. Lubicz , G. Martinelli , M. Papinutto , F. Rapuano , C. T. Sachrajda , : , S. P. Qcd R. collaboration

We use diagrammatic perturbation theory to construct an effective shell-model operator for the neutrinoless double-beta decay of 82Se. The starting point is the same Bonn-C nucleon-nucleon interaction that is used to generate the…

Nuclear Theory · Physics 2009-08-03 Jonathan Engel , Gaute Hagen

I review the status of lattice calculations of heavy-light weak matrix elements, concentrating on semileptonic B decays to light mesons, B -> K* gamma, the B meson decay constant, f_B, and the mixing parameter B_B.

High Energy Physics - Lattice · Physics 2009-03-20 Jonathan Flynn

We present the NLO corrections to the Wilson coefficients of the Delta F = 2 Hamiltonians in the strong interacting sector of the MSSM, responsible for neutral meson oscillations. Such corrections, combined with the NLO anomalous dimension…

High Energy Physics - Phenomenology · Physics 2007-05-23 M. Ciuchini , E. Franco , D. Guadagnoli , V. Lubicz , V. Porretti , L. Silvestrini

We report on our computation of the hadronic matrix elements of the four-quark operators needed for the study of $K^0-{\bar K^0}$ mixing beyond the Standard Model (SM). We consider nf=2+1 Domain-Wall fermions on Iwasaki gauge action with…

High Energy Physics - Lattice · Physics 2012-12-13 Nicolas Garron , Peter A Boyle , Renwick J Hudspith , Andrew T Lytle

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

I summarize the observables constraining the B_s-B_s-bar mixing complex and present a new calculation of the element Gamma_{12}^s of the decay matrix. Gamma_{12}^s enters the prediction of the width difference Delta Gamma_s, for which we…

High Energy Physics - Phenomenology · Physics 2010-11-03 Ulrich Nierste

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…

Using the hadronic matrix elements from the lattice, B_K and xi_s, involving only the 4-quark operators for Delta flavor (F) = 2 Hamiltonian relevant for K, B_d and B_s mixing, along with V_cb, we deduce a non-trivial constraint on the SM,…

High Energy Physics - Phenomenology · Physics 2008-11-26 Enrico Lunghi , Amarjit Soni

We present our recent results for the B-parameters, which parameterize the \Delta B=2 transition amplitudes. Calculations are made in quenched QCD at \beta=5.7, 5.9, and 6.1, using NRQCD for heavy quark and the $O(a)$-improved action for…

We present results for the non-perturbative renormalisation of four-fermion operators with two flavours of dynamical quarks. We consider both fully relativistic left current-left current operators, and a full basis for $\Delta B=2$…

High Energy Physics - Lattice · Physics 2008-11-26 P. Dimopoulos , G. Herdoiza , F. Palombi , M. Papinutto , C. Pena , A. Vladikas , H. Wittig

Lattice calculations of matrix elements involving heavy-light quark bilinears are of interest in calculating a variety of properties of B and D mesons, including decay constants and mixing parameters. A large source of uncertainty in the…

High Energy Physics - Lattice · Physics 2013-11-13 Oscar F. Hernandez , Brian R. Hill

We perform a study of matrix elements relevant for the Delta I=1/2 rule and the direct CP-violation parameter epsilon-prime from first principles by computer simulation in Lattice QCD. We use staggered (Kogut-Susskind) fermions, and employ…

High Energy Physics - Lattice · Physics 2008-11-26 D. Pekurovsky , G. Kilcup

Theory predictions of heavy-hadron lifetime ratios critically depend on precise determinations of the dimension-six spectator effects arising from the double insertion of the weak effective $|\Delta B| = 1$ Hamiltonian. In the presence of…

High Energy Physics - Phenomenology · Physics 2025-04-16 Matthew Black , Martin Lang , Alexander Lenz , Zachary Wüthrich

We analyze the form factors parametrizing the $B_c \to J/\psi, \eta_c$ matrix elements of the operators in a generalized low-energy $b \to c$ semileptonic Hamiltonian. We consider an expansion in nonrelativistic QCD, classifying the heavy…

High Energy Physics - Phenomenology · Physics 2022-09-21 P. Colangelo , F. De Fazio , F. Loparco , N. Losacco , M. Novoa-Brunet

Massive on-shell operator matrix elements and self-energy diagrams with outer gluon lines are calculated analytically at $O(\alpha_s^2)$, using Mellin-Barnes integrals and representations through generalized hypergeometric functions. This…

High Energy Physics - Phenomenology · Physics 2008-11-26 I. Bierenbaum , J. Blümlein , S. Klein

We present a perturbative calculation of the renormalization constants for the $\Delta B=2$ four-quark operators, which is needed to evaluate the bag parameters $B_B$ and $B_S$ in lattice QCD. The one-loop coefficients are calculated for…

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

We report progress in our lattice study of hadronic weak matrix elements relevant for the Delta I = 1/2 rule and epsilon-prime. The presented results are from our first runs on a quenched ensemble with beta=6.0 and a dynamical Nf=2 ensemble…

High Energy Physics - Lattice · Physics 2009-10-30 Dmitry Pekurovsky , Greg Kilcup