2008/01/28 by A. Freitas, Ayres Freitas, Ulrich Haisch · 1 citation
Physics and Astronomy · #Dark Matter and Cosmic Phenomena #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #hep-ex #hep-ph
paper · pdf · doi:10.1103/physrevd.77.093008
published as Phys.Rev.D77:093008,2008 · RevTeX4, 11pp
arxiv created 2008/01/28 · openalex publication_date 2008/05/20 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
We calculate the leading order corrections to the B\ensuremath→Xs\ensuremathγ decay in the standard model with two large flat universal extra dimensions. We find that the contributions involving the exchange of Kaluza-Klein modes of the physical scalar field a(kl)^\ifmmode±\else\textpm\fi depend logarithmically on the ultraviolet cutoff scale \ensuremathΛ. We emphasize that all flavor-changing neutral current transitions suffer from this problem. Although the ultraviolet sensitivity weakens the lower bound on the inverse compactification radius 1/R that follows from B\ensuremath→Xs\ensuremathγ, the constraint remains stronger than any other available direct measurement. After performing a careful study of the potential impact of cutoff and higher-order effects, we find 1/R>650 GeV at 95% confidence level if errors are combined in quadrature. Our limit is at variance with the parameter region 1/R\ensuremath\lesssim600 GeV preferred by dark matter constraints.