Probing new physics in rare charm processes

Abstract

We explore the sensitivity of the flavour changing neutral currents among c and u quarks in the context of the Minimal Supersymmetric Standard Model. The standard model rate for c->u gamma can be enhanced by up to two orders of magnitudes in general MSSM, while the c->ul^+l^- rate can be enhanced by at most a factor of three. The most suitable hadronic observable to probe the c->u gamma transition is the decay B_c->B_u^* gamma or the difference in decay rates of D^0->rho^0 gamma and D^0->omega gamma, since they are relatively free of the long distance contributions. The c ->ul^+l^- transition may be probed in D ->pi l^+l^- decays at high high di-lepton mass and we predict the long distance contributions for these modes.

Comments: 7 pages, talk at the Cairo International Conference on High Energy Physics, 9-14 January 2001, Cairo, Egipt