标题： 中性 $B_s$ 介子的寿命差异及其影响 显示英文标题

标题： Lifetime Difference of Neutral $B_s$ Mesons and its Implications

摘要： 我们讨论在重夸克展开中下一阶近似下，$\Delta\Gamma_{B_s}$之间宽度差的计算，这是针对$B_s$质量本征态的。$1/m_b$修正被估计通常会将领先阶结果减少$30\%$。 当前估计的误差$(\Delta\Gamma/\Gamma)_{B_s} = 0.16^{+0.11}_{-0.09}$可以通过确定$\langle \bar{B}_s |(\bar b_is_i)_{S-P}(\bar b_js_j)_{S-P}| B_s\rangle$的值和在$10\%$的精度下应最终达到$(\Delta\Gamma/\Gamma)_{B_s}$。我们简要提及测量$(\Delta\Gamma/\Gamma)_{B_s}$的策略，以及其对$\Delta M_{B_s}$、CKM参数和未标记的$B_s$样本中CP破坏观测的约束影响。 显示英文摘要

摘要： We discuss the calculation of the width difference $\Delta\Gamma_{B_s}$ between the $B_s$ mass eigenstates to next-to-leading order in the heavy quark expansion. $1/m_b$-corrections are estimated to reduce the leading order result by typically $30\%$. The error of the present estimate $(\Delta\Gamma/\Gamma)_{B_s} = 0.16^{+0.11}_{-0.09}$ could be substantially improved by pinning down the value of $\langle \bar{B}_s |(\bar b_is_i)_{S-P}(\bar b_js_j)_{S-P}| B_s\rangle$ and an accuracy of $10\%$ in $(\Delta\Gamma/\Gamma)_{B_s}$ should eventually be reached. We briefly mention strategies to measure $(\Delta\Gamma/\Gamma)_{B_s}$, and its implications for constraints on $\Delta M_{B_s}$, CKM parameters and the observation of CP violation in untagged $B_s$ samples.