Higher-order perturbative corrections to b → c transitions at zero recoil
نویسندگان
چکیده
منابع مشابه
Higher-Order Perturbative Corrections to b → c Transitions at Zero Recoil
We estimate the two-loop perturbative corrections to zero-recoil matrix elements of the flavour-changing currents c̄ γμb and c̄ γγ5 b by calculating the terms of order nf α 2 s and substituting the dependence on the number of flavours by the first coefficient of the β-function. Both for vector and axial vector currents, we find moderate twoloop corrections below 1% in magnitude. Using the Brodsky...
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ژورنال
عنوان ژورنال: Physics Letters B
سال: 1995
ISSN: 0370-2693
DOI: 10.1016/0370-2693(95)80016-q