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arXiv · hep-lat/0309134

$B_K$ from twisted mass QCD

P. Dimopoulos·J. Heitger·C. Pena·S. Sint·A. Vladikas
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Abstract

We present some preliminary results for $B_K$ at $β=6.0$, using the twisted mass QCD formalism for the computation of bare matrix elements of the $ΔS=2$ operator. The main advantage of the method is that mixing with other $d=6$ operators under renormalisation is avoided. Moreover the operator renormalisation is performed in the Schrödinger functional (SF) framework, using earlier results of our collaboration for the corresponding step scaling function.

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P. Dimopoulos, J. Heitger, C. Pena, S. Sint, A. Vladikas. 2003-09-19. $B_K$ from twisted mass QCD. https://doi.org/10.1016/s0920-5632(03)02565-9

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