Comment on nonperturbative effects in B > X_{s}γ
Abstract
Uncertainties in the theoretical prediction for the inclusive B > X_{s}γ decay rate are discussed. We emphasize that there is no operator product expansion for this process. Nonetheless, some nonperturbative effects involving a virtual c c loop are calculable using the operator product expansion. They give a contribution to the decay rate that involves the B meson matrix element of an infinite tower of operators. The higher dimension operators give effects that are only suppressed by powers of m_{b}Λ_{QCD}/m^{2}_{c} ~ 0.6, but come with small coefficients.
 Publication:

Physics Letters B
 Pub Date:
 February 1997
 DOI:
 10.1016/S03702693(97)003043
 arXiv:
 arXiv:hepph/9702322
 Bibcode:
 1997PhLB..402..178L
 Keywords:

 High Energy Physics  Phenomenology
 EPrint:
 9 pages revtex, 2 figures included