基于HIAF SRing的并束实验设计及研究

Design and Research of Merging Experiment Based on HIAF SRing

超重核的真空衰变对于验证量子电动力学至关重要,由于过去的固定靶实验中,核外电子干扰正负电子对的测量,国际上尚未观测到该现象。提出基于HIAF SRing的并束实验方案,通过^(238)U^(92+)在自由空间碰撞,排除了核外电子的影响。根据亮度理论,结合对交叉角度、Laslett频移和束束相互作用的分析,优化得到1.9×10^(24)cm^(-2)s^(-1)的峰值亮度,基本满足了实验需求。

Vacuum decay phenomenon of superheavy nucleus is a problem of fundamental interest to verify quantum electrodynamics. As the shell electrons interfere the detection of electron-positron pairs in the fixed target experiments in the past, it＇s still not corroborated. A new merging experiment scheme is proposed in this paper. The interference of shell electrons is eliminated by collisions of 238U92＋ in free space. According to the luminosity theory and the analyses of crossing angle, Laslett tune shift and beam-beam interaction, an optimized peak luminosity of 1.9×10^24 cm^-2·s^-1 is achieved. It meets the requirements of merging experiment essentially.