Heavy-to-light currents at NNLO in SCET and semi-inclusive anti-B ---> X(s) l+ l- decay

Abstract

We perform the two-loop matching calculation for heavy-to-light currents from QCD onto soft-collinear effective theory for the complete set of Dirac structures. The newly obtained matching coefficients enter several phenomenological applications, of which we discuss heavy-to-light form factor ratios and exclusive radiative decays, as well as the semi-inclusive decay anti-B ---> X(s) l+ l-. For this decay, we observe a significant shift of the forward-backward asymmetry zero and find q_0^2 = (3.34 +0.22 -0.25) GeV^2 for an invariant mass cut m_X^cut=2.0 GeV.

Comments: 38 pages, 5 figures. The renormalized form factors and matching coefficients are attached in electronic form to the source of the present submission