ar X iv : h ep - p h / 99 01 25 2 v 2 2 3 M ar 1 99 9 IJS - TP - 99 / 01 TECHNION - PH - 99 - 02
نویسندگان
چکیده
We propose the B c → B * u γ decay as the most suitable probe for the flavour changing neutral transition c → uγ. We estimate the short and long distance contributions to this decay within the standard model and we find them to be comparable; this is in contrast to radia-tive decays of D mesons, that are completely dominated by the long distance contributions. Since the c → uγ transition is very sensitive to the physics beyond the standard model, the standard model prediction Br(B c → B * u γ) ∼ 10 −8 obtained here opens a new window for future experiments. The detection of B c → B * u γ decay at branching ratio well above 10 −8 would signal new physics. In addition we study the s → dγ transition in B s → B * d γ decay and we find it to be dominated by the long distance contribution. We use the Isgur-Scora-Grinstein-Wise (ISGW) constituent quark model for the calculation of these decays.
منابع مشابه
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Analytic results for the complete set of two-loop self-energy master integrals on shell with one mass are calculated.
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