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arXiv · 1302.7240

Bounds on the compactification scale of two universal extra dimensions from exclusive $b \to s γ$ decays

Pietro Biancofiore
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Abstract

The exclusive radiative $B \to K^* γ$, $B \to K^*_2 γ$, $B_s \to ϕγ$ and $Λ_b \to Λγ$ decays are studied in a new physics scenario with two universal extra dimensions compactified on a chiral square. The computed branching fractions depend on the size $R$ of the extra dimensions, and a comparison with the available measurements allows us to put bounds on such a fundamental parameter. From the mode $B^0 \to K^{*0} γ$ we obtain the most stringent bound: $1 \over R>710$ GeV.

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Pietro Biancofiore. 2013-02-28. Bounds on the compactification scale of two universal extra dimensions from exclusive $b \to s γ$ decays. https://doi.org/10.1088/0954-3899%2F40%2F6%2F065006

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