The search for neutrinoless double beta decay of EXO-200 and nEXO with barium tagging

报告题目：The search for neutrinoless double beta decay of EXO-200 and nEXO with barium tagging

报 告 人：兰阳（加拿大麦吉尔大学）

时    间： 2020/4/14(星期三)/15:00

地    点：物理学院 LE201

邀 请 人：吴兴刚 教授

报告摘要：

The properties of neutrino remains to be one of the biggest mysteries in particle physics. Neutrinoless double beta decay (0νββ) is the most sensitive approach to validate whether neutrinos are their own antiparticles and to reveal their absolute mass scale. If detected, 0νββ will also be the first lepton-number violating process and help to explain the matter-antimatter asymmetry in our universe. The EXO (Enriched Xenon Observatory) is searching for 0νββ in xenon-136. Our recently completed experiment EXO-200 found xenon-136 has half-life  �₁⸝₂>3.5×10²⁵ years. The upgraded experiment nEXO will have 0νββ �₁⸝₂ sensitivity above10²⁸ years. The sensitivity of nEXO is limited by its background level. Barium tagging is the ultimate method for reducing the background. An ion trap is being developed for the barium tagging purpose of nEXO to reach its ultimate sensitivity on 0νββ. Prototypes of the ion trap has been built and tested, the experiment results demonstrated successful ion trapping, cooling and mass filtering for barium tagging.

报告人介绍：

兰阳，加拿大麦吉尔大学 博士后，英属哥伦比亚大学 博士，无中微子双贝塔衰变实验 国际合作组 EXO-200 和 nEXO 成员。2011-2012本科期间参与华中科技大学 引力中心 光频标组，仿真和设计了用于光钟的初代离子阱。2013-2014年硕士期间在英属哥伦比亚大学 物理与天文学院 研究声学和音乐声学，为中国古琴和箫进行了声学测量和建模，优化了箫的声学设计并制出性能卓越的成品箫。2015年至今：参与加拿大粒子与核物理国家实验室 TITAN组的短寿命同位素精密质量测量实验；参与EXO-200地下实验并担任其运行最后2年的数据质量分析员；负责为nEXO设计，仿真和搭建用于 barium tagging 的离子阱。