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Related papers: Matching the Electroweak Penquins Q_7 and Q_8

200 papers

Status report is made of our quenched study of heavy-light matrix elements employing the Wilson quark action for heavy quark. Results obtained up to now with 200 configurations at $\beta=6.1$ on a $24^3\times64$ lattice and with 100…

High Energy Physics - Lattice · Physics 2012-08-27 JLQCD Collaboration

We use the chiral quark model to estimate the coefficients of the weak chiral lagrangian as obtained from the bosonization of the ten relevant operators of the $\Delta S = 1$ effective quark lagrangian. All contributions of order $N_c^2$ as…

High Energy Physics - Phenomenology · Physics 2009-10-28 V. Antonelli , S. Bertolini , J. O. Eeg , M. Fabbrichesi , E. I. Lashin

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 present a recent analysis of epsilon'/epsilon in the 1/N_c expansion. We show that the 1/N_c corrections to the matrix element of Q_6 are large and positive, indicating a Delta I=1/2 enhancement similar to the one of Q_1 and Q_2 which…

High Energy Physics - Phenomenology · Physics 2016-11-23 T. Hambye , G. O. Koehler , E. A. Paschos , P. H. Soldan

Some rare hadronic decays of B mesons, such as B->pi K, are sensitive to isospin-violating contributions from physics beyond the Standard Model. Although commonly referred to as electroweak penguins, such contributions can often arise…

High Energy Physics - Phenomenology · Physics 2009-10-31 Yuval Grossman , Alexander L. Kagan , Matthias Neubert

We present a recent analysis of epsilon'/epsilon in the 1/N_c expansion. We show that the 1/N_c corrections to the matrix element of Q_6 are large and positive, indicating a Delta I = 1/2 enhancement similar to the one of Q_1 and Q_2 which…

High Energy Physics - Phenomenology · Physics 2009-10-31 T. Hambye , P. H. Soldan

In our subgroup, we focused on penguin physics from various different angles. Our discussions included: (1) A method to extract one of the angles of the unitarity triangle $\phi_2$; (2) Methods to extract $\phi_3$ from $B\to K\pi$ decays;…

High Energy Physics - Phenomenology · Physics 2009-09-25 A. I. Sanda

We explore application of the domain wall fermion formalism of lattice QCD to calculate the $K\to\pi\pi$ decay amplitudes in terms of the $K\to\pi$ and $K\to 0$ hadronic matrix elements through relations derived in chiral perturbation…

The strong isospin-breaking correction, Omega_{st}, which appears in estimates of the Standard Model value for the direct CP-violating ratio epsilon'/epsilon, is evaluated to next-to-leading order (NLO) in the chiral expansion using Chiral…

High Energy Physics - Phenomenology · Physics 2014-11-17 C. E. Wolfe , K. Maltman

We update the profile of the CKM matrix. The apex (rhobar,etabar) of the Unitarity Triangle is given by means of a global fit. We propose to include therein sin2alpha from the CP-violating asymmetries in B0->rho+rho-, using isospin to…

High Energy Physics - Phenomenology · Physics 2008-11-26 J. Charles , A. Hocker , H. Lacker , S. Laplace , F. R. Le Diberder , J. Malcles , J. Ocariz , M. Pivk , L. Roos

We reanalyse the ratio $\varepsilon'/\varepsilon$ in the Standard Model (SM) using most recent hadronic matrix elements from the RBC-UKQCD collaboration in combination with most important NNLO QCD corrections to electroweak penguin…

High Energy Physics - Phenomenology · Physics 2020-08-26 Jason Aebischer , Christoph Bobeth , Andrzej J. Buras

Using the pole shifting procedure of the modified quenched approximation (MQA) to cure the exceptional configuration problem, accurate hadron hadron spectrum calculations can be obtained at very light quark mass. Here we use the MQA to…

High Energy Physics - Lattice · Physics 2009-10-31 W. Bardeen , A. Duncan , E. Eichten , H. B. Thacker

The experimental value for the isospin amplitude Re(A_2) in K->pi pi decays has been successfully explained within the Standard Model, both within large N approach to QCD and by QCD lattice calculations. On the other hand in both approaches…

High Energy Physics - Phenomenology · Physics 2014-07-10 Andrzej J. Buras , Fulvia De Fazio , Jennifer Girrbach

Using unimproved and non-perturbatively O(a) improved Wilson fermions, results are given for the three lowest moments of unpolarised nucleon structure functions. Renormalisation, chiral extrapolation and the continuum limit of the matrix…

High Energy Physics - Lattice · Physics 2008-11-26 S. Capitani , M. Gockeler , R. Horsley , D. Pleiter , P. Rakow , H. Stuben , G. Schierholz

Determinations of the CKM phase $\gamma$ from weak nonleptonic $B$ decays are affected by electroweak (EW) penguins and rescattering effects. In this talk it is explained how the EW penguin effects can be controlled with the help of SU(3)…

High Energy Physics - Phenomenology · Physics 2010-11-23 Dan Pirjol

We calculate the two-loop $10 \times 10$ anomalous dimension matrix ${\cal O}(\alpha_s^{2})$ involving current-current operators, QCD penguin operators, and electroweak penguin operators especially relevant for $\Delta S=1$ weak…

High Energy Physics - Phenomenology · Physics 2009-10-22 Andrzej J. Buras , Matthias Jamin , Markus E. Lautenbacher , Peter H. Weisz

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

I shortly review the present status of the theoretical calculations of epsilon'/epsilon and the comparison with the present experimental results. I discuss the role of higher order chiral corrections and in general of non-factorizable…

High Energy Physics - Phenomenology · Physics 2009-11-07 Stefano Bertolini

We perform a Next-to-Leading order analysis of Delta S=2 processes beyond the Standard Model. Combining the recently computed NLO anomalous dimensions and the B parameters of the most general Delta S=2 effective Hamiltonian, we give an…

High Energy Physics - Phenomenology · Physics 2009-10-31 M. Ciuchini , L. Conti , A. Donini , E. Franco , V. Gimenez , L. Giusti , V. Lubicz , G. Martinelli , A. Masiero , I. Scimemi , L. Silvestrini , M. Talevi , A. Vladikas

The three-loop QCD contributions to the vacuum polarization functions of the $Z$ and $W$ bosons at zero momentum are calculated. The top quark is considered to be massive and the other quarks massless. Using these results, we calculate the…

High Energy Physics - Phenomenology · Physics 2011-01-13 L. Avdeev , J. Fleischer , S. Mikhailov , O. Tarasov