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Related papers: B_K from quenched overlap QCD

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We search for direct CP violation in flavor specific B -> K pi decays by measuring the rate asymmetry between charge conjugate modes. The search is performed on a data sample of 11.1 million B B bar events recorded on the Upsilon(4S)…

High Energy Physics - Experiment · Physics 2010-05-28 K. Abe

A study of the chiral behavior of pseudoscalar masses and decay constants is carried out in quenched lattice QCD with Wilson fermions. Using the modified quenched approximation (MQA) to cure the exceptional configuration problem, accurate…

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

We calculate results for K to pi and K to 0 matrix elements to next-to-leading order in 2+1 flavor partially quenched chiral perturbation theory. Results are presented for both the Delta I=1/2 and 3/2 channels, for chiral operators…

High Energy Physics - Lattice · Physics 2009-02-23 C. Aubin , J. Laiho , S. Li , M. F. Lin

We present for the first time a master formula for $\varepsilon'/\varepsilon$, the ratio probing direct CP violation in $K \to \pi\pi$ decays, valid in any theory beyond the Standard Model (BSM). The formula makes use of hadronic matrix…

High Energy Physics - Phenomenology · Physics 2019-08-09 Jason Aebischer , Christoph Bobeth , Andrzej J. Buras , Jean-Marc Gérard , David M. Straub

We calculate the hadronic matrix elements to $O(p^4)$ in the chiral expansion for the ($\Delta S =1$) $K^0 \to 2 \pi$ decays and the ($\Delta S=2$) $\bar K^0$-$K^0$ oscillation. This is done within the framework of the chiral quark model.…

High Energy Physics - Phenomenology · Physics 2009-10-30 S. Bertolini , J. O. Eeg , M. Fabbrichesi , E. I. Lashin

I present the status of the elements and parameters of the Cabibbo-Kobayashi-Maskawa (CKM) matrix and summarise the related theoretical progress since "Lepton-Photon 2003". One finds |V_{us}| = 0.2227 +/- 0.0017 from K and tau decays and…

High Energy Physics - Phenomenology · Physics 2009-11-11 Ulrich Nierste

We compute on the lattice the ``bag'' parameters of the five (Delta B = 2) operators of the supersymmetric basis, by combining their values determined in full QCD and in the static limit of HQET. The extrapolation of the QCD results from…

High Energy Physics - Lattice · Physics 2009-11-07 D. Becirevic , V. Gimenez , G. Martinelli , M. Papinutto , J. Reyes

In the standard model (SM), the CP violation is introduced through a single phase in the CKM matrix. The neutral kaon system is one of the most precise channels to test how the SM theory describes the experiment data such as $\epsilon_K$…

High Energy Physics - Lattice · Physics 2012-11-06 Yong-Chull Jang , Weonjong Lee

We study $B_{s}\to KK$ decays in the framework of the PQCD. We show that the branching ratios of $B_{s}\to (K^+ K^-, K^0 \bar{K}^0)$ are about $(22.43, 25.78) \times 10^{-6}$ for $\phi_{3}(\gamma)\simeq72^0$, which are consistent with the…

High Energy Physics - Phenomenology · Physics 2014-11-17 Chuan-Hung Chen

We review the information on the CKM matrix elements, unitarity triangle and CP-violating phases $\alpha, \beta$ and $\gamma$ in the standard model which will be measured in the forthcoming experiments at B factories, HERA-B and hadron…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. Ali

An investigation of CP violation was performed using a total of 24 candidates for B^0 -> J/psi K^0_S decay, with a purity of about 60%. These events were selected from 4.4 million hadronic Z^0 decays recorded by the OPAL detector at LEP. An…

High Energy Physics - Experiment · Physics 2008-11-26 The OPAL Collaboration , K. Ackerstaff et al

Delta I=3/2, K to Pi Pi matrix elements are calculated on 68 configurations of quenched 24^3 x 64 lattices using the DBW2 action, and domain wall fermions with L_s=16. The lattice spacing is a^(-1)=1.3 GeV, corresponding to a physical…

High Energy Physics - Lattice · Physics 2010-03-18 Matthew Lightman , Elaine Goode

Using domain wall fermions, we estimate $B_K(\mu\approx 2 GeV)=0.628(47)$ in quenched QCD which is consistent with previous calculations. At $\gbeta=6.0$ and 5.85 we find the ratio $f_K/m_\rho$ in agreement with the experimental value,…

High Energy Physics - Lattice · Physics 2009-10-30 T. Blum , A. Soni Brookhaven National Lab

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…

We present the inconsistencies which arise in quenched QCD in $\Delta I=1/2$ non-leptonic kaon decays using chiral perturbation theory (ChPT) to one loop. In particular we discuss how the lack of unitarity of the quenched theory invalidates…

High Energy Physics - Lattice · Physics 2016-09-01 C. J. D. Lin , G. Martinelli , E. Pallante , C. T. Sachrajda , G. Villadoro

We have gained enough statistical precision to distinguish signal from noise in matrix elements of all operators relevant for the Delta I=1/2 rule in kaon decays and for the direct CP violation parameter epsilon-prime. We confirm…

High Energy Physics - Lattice · Physics 2007-05-23 D. Pekurovsky , G. Kilcup

The use of chiral perturbation theory in extracting physical K to pi pi matrix elements from matrix elements calculated at unphysical kinematics is outlined. In particular, the possibility of utilizing pions with non-zero momentum in the…

High Energy Physics - Lattice · Physics 2008-11-26 Matthew Lightman

We investigate the future determination of the CKM matrix using theoretically clean quantities, like $B(K^+\to\pi^+\nu\bar\nu)$, $B(K_L\to\pi^0\nu\bar\nu)$ or $\sin 2\beta$, $\sin 2\alpha$ as extracted from CP violation studies in $B$…

High Energy Physics - Phenomenology · Physics 2009-10-09 Gerhard Buchalla , Andrzej J. Buras

We present a high statistics, quenched lattice calculation of the B-parameters $B_{B_d}$ and $B_{B_s}$, computed at lowest order in the HQET. The results were obtained using a sample of 600 quenched gauge field configurations, generated by…

High Energy Physics - Lattice · Physics 2016-09-01 V. Gimenez , G. Martinelli

Recently, we pointed out that chiral transformation properties of penguin operators change in the transition from unquenched to (partially) quenched QCD. As a consequence, new operators appear in (partially) quenched QCD penguins,…

High Energy Physics - Lattice · Physics 2009-11-07 Maarten Golterman , Elisabetta Pallante