اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدPrecision Global Determination of the $Bto X_sgamma$ Decay Rate
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We perform the first global fit to inclusive $Bto X_sgamma$ measurements using a model-independent treatment of the nonperturbative $b$-quark distribution function, with next-to-next-to-leading logarithmic resummation and $mathcal{O}(alpha_s^2)$ fixed-order contributions. The normalization of the $Bto X_sgamma$ decay rate, given by $lvert C_7^{rm incl} V_{tb} V_{ts}^*rvert^2$, is sensitive to physics beyond the Standard Model (SM). We determine $lvert C_7^{rm incl} V_{tb} V_{ts}^* rvert = (14.77 pm 0.51_{rm fit} pm 0.59_{rm theory} pm 0.08_{rm param})times 10^{-3}$, in good agreement with the SM prediction, and the $b$-quark mass $m_b^{1S} = (4.750 pm 0.027_{rm fit} pm 0.033_{rm theory} pm 0.003_{rm param}),mathrm{GeV}$. Our results suggest that the uncertainties in the extracted $Bto X_sgamma$ rate have been underestimated by up to a factor of two, leaving more room for beyond-SM contributions.
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