论文标题
$ e^+e^ - \ rightarrow b^{（*）} \ bar b^{（*）} $交叉部分
Effects of isospin violation in the $e^+e^- \rightarrow B^{(*)}\bar B^{(*)}$ cross sections
论文作者
论文摘要
获得了模型估计值，以实现库仑影响对带电和中性$ b \ b \ b $和$ b^*\ bar b^*$ pairs $ e^+e^ - $ nihihilation的产生和中性$ b \ b \ b $和$ b^*\ bar b $和$ b^*\ bar b^*$对的影响的影响。结果表明，在假设该比率是在梁能量传播的范围内保持不变的假设所获得的带电和中性介子的质量之间的差异可能与$Δm\ sim \ sim 0.03 \，\ mbox {mev} $以$ n（5s）$ $Δm\ sim \ mbox \ mbox \ mbox \ mbox \ mbox \ mbox \ mbox \ Mbox \ mbox {mev} $ \ mbox \ mbox \ mbox \ mbox， $υ（4s）$。因此，根据$υ（4S）$的能量获得的结果，在PDG中给出的错误和中性$ b $ erson的质量之间的差异被强烈低估。 $υ（5s）$的能量上的类似测量值将具有较小的系统变化顺序，以便质量差。在KEK的$ B $工厂计划将来的实验时，应考虑这种情况。
Model estimates are obtained for the influence of Coulomb effects on the ratio of the cross sections for the production of charged and neutral $B\bar B$ and $B^*\bar B^*$ pairs in $e^+e^-$ annihilation. It is shown that the difference between the masses of charged and neutral mesons obtained under the assumption that this ratio is constant on a scale of the order of the beam energy spread can differ from the true one by $δM \sim 0.03\,\mbox{MeV}$ at the energy of $Υ(5S)$ and by $δM \sim 0.4\,\mbox{MeV}$ at the energy of $Υ(4S)$. Thus, the errors given in the PDG for the difference between the masses of charged and neutral $B$ mesons, based on the results obtained at the energy of $Υ(4S)$, are strongly underestimated. Similar measurements at the energy of $Υ(5S)$ will have an order of magnitude smaller systematic shift for the mass difference. This circumstance should be taken into account when planning future experiments at the $B$ factory in KEK.
