Universality and m_X cut effects in B -> Xs l+ l-
High Energy Physics - Phenomenology
2014-11-18 v2 High Energy Physics - Experiment
Abstract
The most precise comparison between theory and experiment for the B -> Xs l+ l- rate is in the low q^2 region, but the hadronic uncertainties associated with an experimentally required cut on m_X potentially spoil the search for new physics in these decays. We show that a 10-30% reduction of d\Gamma(B -> Xs l+ l-) / dq^2 due to the m_X cut can be accurately computed using the B -> X_s gamma shape function. The effect is universal for all short distance contributions in the limit m_X^2 << m_B^2, and this universality is spoiled neither by realistic values of the m_X cut nor by alpha_s corrections. Both the differential decay rate and forward-backward asymmetry with an m_X cut are computed.
Cite
@article{arxiv.hep-ph/0512191,
title = {Universality and m_X cut effects in B -> Xs l+ l-},
author = {Keith S. M. Lee and Zoltan Ligeti and Iain W. Stewart and Frank J. Tackmann},
journal= {arXiv preprint arXiv:hep-ph/0512191},
year = {2014}
}
Comments
5 pages, journal version