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Probing new physics in rare charm processes

Sasa Prelovsek
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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.

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Sasa Prelovsek. 2001-04-17. Probing new physics in rare charm processes. https://arxiv.org/abs/hep-ph/0104159

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