Probing the helicity structure of b → sγ in Λ b → Λ γ
نویسنده
چکیده
We investigate the rare decay Λb → Λγ which receives both short and long distance contributions. We estimate the long distance contributions and find them very small. The form factors are obtained from Λc → Λlν̄l using heavy quark symmetry and a pole model. The short distance piece opens a window to new physics and we discuss the sensitivity of Λb → Λγ to such effects.
منابع مشابه
ar X iv : h ep - p h / 06 05 24 5 v 1 2 3 M ay 2 00 6 Photon helicity in Λ b →
Radiative decays of polarized Λb baryons represent an attractive possibility to measure the helicity of the photon emitted in the b → sγ quark transition and thus to subject the Standard Model to a stringent test at existing and future hadron colliders. The most abundant mode, Λ(1116)γ, is experimentally very challenging because of the long decay length of the Λ(1116). We show that the experime...
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