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arXiv · 0810.2443

K-meson vector and tensor decay constants and BK-parameter from Nf=2 tmQCD

P. Dimopoulos·R. Frezzotti·V. Gimenez·V. Lubicz·F. Mescia·G. C. Rossi·S. Simula·A. Vladikas
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Abstract

We present work in progress on the computation of the K-meson vector and tensor decay constants, as well as the B-parameter in Kaon oscillations. Our simulations are performed in a partially quenched setup, with two dynamical (sea) Wilson quark flavours, having a maximally twisted mass term. Valence quarks are either of the standard or the Osterwalder-Seiler maximally twisted variety. These two regularizations can be suitably combined in order to obtain a BK parameter which is both multiplicatively renormalizable and O(a) improved.

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P. Dimopoulos, R. Frezzotti, V. Gimenez, V. Lubicz, F. Mescia, G. C. Rossi, S. Simula, A. Vladikas. 2008-10-14. K-meson vector and tensor decay constants and BK-parameter from Nf=2 tmQCD. https://arxiv.org/abs/0810.2443

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