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B_K in the chiral limit within the 1/Nc expansion

Santiago Peris
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Abstract

I report on a recent calculation done in collaboration with E. de Rafael (hep-ph/0006146 v3) of the invariant B_K factor of K-Kbar mixing in the chiral limit and to next-to- leading order in the 1/Nc expansion. This calculation is, to the best of our knowledge, the first example of a calculation of B_K in which there is an explicit analytic cancellation of the mu renormalization scale and the scheme dependence between the Wilson coefficient and the corresponding kaon matrix element. I try to emphasize the ideas involved in the approach and how the method could be applied to other physical situations, rather than the details of the numerical analysis for which I refer the reader to the above reference.

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Santiago Peris. 2001-03-20. B_K in the chiral limit within the 1/Nc expansion. https://doi.org/10.1016/s0920-5632(01)01152-5

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