The B -> X_s gamma gamma rare decay
  The rare decay B -> X_s gamma gamma is studied in the Standard Model (SM) and in two different versions (Model I and Model II) of the Two Higgs Doublet Model (2HDM). In the SM the branching ratio into ``hard photons'' is about 10^(-7) and can be appreciably different in the 2HDM. We also introduce a forward-backward asymmetry which gives an additional handle to discriminate different models. 
Laura Reina (BNL), Giulia Ricciardi (Naple University), Amarjit Soni   (BNL)