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Bound on minimal universal extra dimensions from Bbar -> X_s gamma

Ulrich Haisch·Andreas Weiler
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Abstract

We reexamine the constraints on universal extra dimensional models arising from the inclusive radiative Bbar -> X_s gamma decay. We take into account the leading order contributions due to the exchange of Kaluza-Klein modes as well as the available next-to-next-to-leading order corrections to the Bbar -> X_s gamma branching ratio in the standard model. For the case of one large flat universal extra dimension, we obtain a lower bound on the inverse compactification radius 1/R > 600 GeV at 95% confidence level that is independent of the Higgs mass.

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Ulrich Haisch, Andreas Weiler. 2007-08-22. Bound on minimal universal extra dimensions from Bbar -> X_s gamma. https://doi.org/10.1103/physrevd.76.034014

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