English

Chromomagnetic Dipole-Operator Corrections in Bbar -> X_sgamma at O(beta_0 alpha_s^2)

High Energy Physics - Phenomenology 2010-12-13 v2 High Energy Physics - Experiment

Abstract

We calculate the fermionic corrections to the photon-energy spectrum of Bbar -> X_sgamma which arise from the self-interference of the chromomagnetic dipole operator Q_8 at next-to-next-to-leading order by applying naive non-abelianization. The resulting O(beta_0 alpha_s^2) correction to the Bbar -> X_sgamma branching ratio amounts to a relative shift of +0.12% (+0.27%) for a photon-energy cut of 1.6 GeV (1.0 GeV). We also comment on the potential size of resummation and non-perturbative effects related to Q_8.

Keywords

Cite

@article{arxiv.1009.2144,
  title  = {Chromomagnetic Dipole-Operator Corrections in Bbar -> X_sgamma at O(beta_0 alpha_s^2)},
  author = {Andrea Ferroglia and Ulrich Haisch},
  journal= {arXiv preprint arXiv:1009.2144},
  year   = {2010}
}

Comments

8 pages, 4 figures; v2: matches version published in PRD