报告内容 摘要 |
The properties of neutrino remain 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. 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 𝘛₁⸝₂>3.5×10⟡⁵ years. The upgraded experiment nEXO will have 0νββ 𝘛₁⸝₂sensitivity above10⟡⁸ 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 further improve its sensitivity on 0νββ. |
