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تسجيل مستخدم جديد$Bto K^ast_2(1430)ell^+ell^-$ distributions in Standard Model at large recoil
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We study the rare decay $Bto K_2^ast(1430)(to Kpi)ell^+ell^-$ in the Standard Model and beyond. Working in the transversity basis, we exploit the relations between the heavy-to-light form factors in the limit of heavy quark ($m_bto infty$) and large energy ($E_{K_2^ast}to infty$) of the $K^ast_2$ meson. This allows us to construct observables where at leading order in $Lambda_{rm QCD}/m_b$ and $alpha_s$ the form factor dependence involving the $Bto K^ast_2$ transitions cancels. Higher order corrections are systematically incorporated in the numerical analysis. In the Standard Model the decay has a sizable branching ratio and therefore a large number of events can be expected at LHCb. Going beyond the Standard Model, we explore the implications of the global fit to presently available $bto sell^+ell^-$ data on the $Bto K_2^ast ell^+ell^-$ observables.
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