The electromagnetic penguin diagram in B mesons decays, like b->s gamma and b->d gamma, allows precise measurements of the top quark couplings V_ts and V_td. The strength of these decays may also be enhanced by the presence of non-Standard Model contributions. In minimal supersymmetric models, for example, the W can be replaced by a charged Higgs leading to significant enhancements in the branching fraction.

In the first three years of running the BaBar experiment has accumulated the world's largest B meson dataset. This large dataset and the state of the art detection systems employed at BaBar allow measurements and searches of unprecedented precision.

A comprehensive program to study these decays is now underway. A Radiative Penguin Analysis Working Group (AWG) has been set up to study these processes. First results from BaBar for the exclusive mode B->K*(892) gamma were presented at ICHEP2000, Osaka (Japan).

Currently, Steve Playfer and James Swain are deeply involved in the study of the inclusive b->s gamma and several rare exclusive modes.

The AWG has a home page (accessible to collaborators only) at http://www.slac.stanford.edu/BFROOT/www/Physics/Analysis/AWG/RadPenguins.
The Osaka paper can be found at http://www.slac.stanford.edu/BFROOT/www/doc/public/conf_pubs/2000/babar-conf-0012.ps.gz.