English

Possible New Physics Signals in b -> s gamma and b -> s l^+ l^-

High Energy Physics - Phenomenology 2007-05-23 v2

Abstract

We consider possible new physics contributions to b\to s l^+ l^- assuming the new physics modifies (chromo)magnetic and electric form factors in b\to s \gamma^* and b\to s g with the same chirality structure as in the standard model. Parametrizing the new physics effects on b\to s \gamma^* and b\to s g in terms of four real parameters, one finds that there are enough region of parameter space in which the measured branching ratio for B \to X_s \gamma can be accomodated, and the predicted CP violation effect could be as large as \sim 30%. Moreover, the branching ratio and the forward-backward asymmetry of a lepton in B \to X_s l^+ l^- and the tau polarization asymmetry in B \to X_s \tau^+ \tau^- can be deviated from the SM predictions by a factor of \sim 2, which can be accessible at B factories. We also discuss these observables in a specific class of supersymmetric models with gluino-mediated flavor changing neutral current (FCNC).

Keywords

Cite

@article{arxiv.hep-ph/9810336,
  title  = {Possible New Physics Signals in b -> s gamma and b -> s l^+ l^-},
  author = {Yeong Gyun Kim and P. Ko and Jae Sik Lee},
  journal= {arXiv preprint arXiv:hep-ph/9810336},
  year   = {2007}
}

Comments

30 pages, 10 figures. Updated data on b -> s gamma are used, to appear Nucl. Phys. B