论文标题
$ b \ tox_sγ$衰减率的精确全局确定
Precision Global Determination of the $B\to X_sγ$ Decay Rate
论文作者
论文摘要
我们使用非扰动$ b $ QUARK分布功能的模型处理函数进行了第一个全局拟合，以x_sγ$测量值进行X_Sγ$测量，并具有近代到接头的对数重新启动和$ \ MATHCAL {O}（O}（O}（α_S^2））$固定级别贡献。 $ b \ tox_sγ$衰减率的归一化，由$ \ lvert c_7^{\ rm incl} v_ {tb} v_ {tb} v_ {ts}^*\ rvert^2 $，对超出标准模型（SM）的物理学敏感。我们确定$ \ lvert c_7^{\ rm-gent} v_ {tb} v_ {ts}^* \ rvert =（14.77 \ pm 0.51 _ {\ rm fit} \ rm fit} \ pm 0.59 _ {\ rm理论} SM预测和$ B $ -QUARK MASS $ M_B^{1S} =（4.750 \ pm 0.027 _ {\ rm Fit} \ pm 0.033 _ {\ rm理论} \ pm 0.003 _ {\ rm param}）我们的结果表明，提取的$ b \ tox_sγ$速率的不确定性被低估了两个倍，为超越SM贡献留下了更多的空间。
We perform the first global fit to inclusive $B\to X_sγ$ measurements using a model-independent treatment of the nonperturbative $b$-quark distribution function, with next-to-next-to-leading logarithmic resummation and $\mathcal{O}(α_s^2)$ fixed-order contributions. The normalization of the $B\to X_sγ$ 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 $B\to X_sγ$ rate have been underestimated by up to a factor of two, leaving more room for beyond-SM contributions.
