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arXiv · hep-ph/9205219

A General Lower Bound for Radiative B Decay

David Atwood·C. P. Burgess·A. Soni
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Abstract

In a wide class of models -- including the standard model -- flavor-changing neutral currents are suppressed by an approximate chiral symmetry of the low-energy lagrangian. This symmetry allows the derivation of general relations among low-energy flavour-changing processes. We derive one such: the relative sizes of the decay rates b --> s gamma, b --> d gamma and s --> d gamma. Together with a unitarity-related lower bound on the rate for the strangeness-changing hyperon decay Omega^- --> Xi^- γwe obtain a reasonably model-independent lower bound for the inclusive b --> s gamma rate.

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David Atwood, C. P. Burgess, A. Soni. 1992-08-07. A General Lower Bound for Radiative B Decay. https://arxiv.org/abs/hep-ph/9205219

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