arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2009.08183hep-phnucl-exnucl-th
收藏

小$ \sqrt{s}$时$e^+ e^-\rightarrowπ^+π^-$中的双光子交换效应

Two-photon exchange effects in $e^+ e^-\rightarrowπ^+π^-$ at small $ \sqrt{s}$

Zhong-Hua Zhao, Hui-Yun Cao, Hai-Qing Zhou

摘要:

本文在强子模型下讨论了小$\sqrt{s}$时$e^+e^- \rightarrow π^+ π^-$中的双光子交换效应。在极限$m_e\rightarrow 0$中,TPE对幅度的贡献可以由一个标量函数$\overline{c}_{1}^{(2γ)}$来描述。该函数与单光子交换$c_{1}^{(1γ)}$中相应贡献之间的比率反映了TPE校正的所有信息。给出了这一比值的数值结果,并利用人工函数对数值结果进行了拟合。后者可方便地用于进一步的实验数据分析。计算结果表明,在$\sqrt{s}\sim 0.7$ GeV处,$e^+e^- \rightarrow π^+ π^-$微分截面的不对称性约为$-4\%$.

英文摘要:

In this work, the two-photon-exchange (TPE) effects in $e^+e^- \rightarrow π^+ π^-$ at small $\sqrt{s}$ are discussed within a hadronic model. In the limit $m_e\rightarrow 0$, the TPE contribution to the amplitude can be described by one scalar function $\overline{c}_{1}^{(2γ)}$. The ratio between this function and the corresponding contribution in one-photon exchange $c_{1}^{(1γ)}$ reflects all the information of the TPE corrections. The numerical results on this ratio are presented and an artificial function is used to fit the numerical results. The latter can be used conveniently in the further experimental data analysis. The numerical results show the asymmetry of the differential cross sections in $e^+e^- \rightarrow π^+ π^-$ is about $-4\%$ at $\sqrt{s}\sim 0.7$ GeV.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑