EXO-200中无中微子双β衰变（0νββ）的宇宙成因本底
核实验
2016-05-20 v2 高能物理 - 实验
仪器与探测器
摘要
随着无中微子双β衰变（0νββ）实验灵敏度提高且探测器材料的内禀放射性降低，先前对本底的微小贡献必须被理解并消除。鉴于此，我们利用EXO-200实验研究了宇宙成因本底。使用EXO-200时间投影室（TPC），测得废物隔离中试厂（WIPP）地下（通过平坦水平表面）的μ子通量为 {\Phi} = 4.07 0.14 (sys) 0.03 (stat) cm s，垂直强度为 = 2.97 (sys) 0.02 (stat) cm s sr。μ子诱导本底的模拟辨识出几种潜在的宇宙成因放射性核素，但只有 137Xe 是EXO-200中 Xe 0νββ 搜寻的显著本底。利用探测器材料上中子俘获产生的 {\gamma} 射线，测量了μ子诱导的中子本底。这提供了 Xe 产额的测量，并检验了中子产生与输运模拟的精度。独立测量的 Xe 中子俘获率与 Xe 衰变率在不确定度内一致。进行了Geant4和FLUKA模拟以估计中子俘获率，这些估计与测量一致在约40%或更好以内。识别 Xe(n,{\gamma}) 事件的能力将允许在未来的0νββ分析中剔除 Xe 本底。
引用
@article{arxiv.1512.06835,
title = {Cosmogenic Backgrounds to 0{\nu}{\beta}{\beta} in EXO-200},
author = {200 Collaboration and J. B. Albert and D. J. Auty and P. S. Barbeau and D. Beck and V. Belov and M. Breidenbach and T. Brunner and A. Burenkov and G. F. Cao and C. Chambers and B. Cleveland and M. Coon and A. Craycraft and T. Daniels and M. Danilov and S. J. Daugherty and J. Davis and S. Delaquis and A. Der Mesrobian-Kabakian and R. DeVoe and T. Didberidze and J. Dilling and A. Dolgolenko and M. J. Dolinski and M. Dunford and W. Fairbank and J. Farine and W. Feldmeier and S. Feyzbakhsh and P. Fierlinger and D. Fudenberg and R. Gornea and K. Graham and G. Gratta and C. Hall and S. Herrin and M. Hughes and M. J. Jewell and A. Johnson and T. N. Johnson and S. Johnston and A. Karelin and L. J. Kaufman and R. Killick and T. Koffas and S. Kravitz and R. Krücken and A. Kuchenkov and K. S. Kumar and D. S. Leonard and C. Licciardi and Y. H. Lin and J. Ling and R. MacLellan and M. G. Marino and B. Mong and D. Moore and O. Njoya and R. Nelson and A. Odian and I. Ostrovskiy and A. Piepke and A. Pocar and C. Y. Prescott and F. Retière and P. C. Rowson and J. J. Russell and A. Schubert and D. Sinclair and E. Smith and V. Stekhanov and M. Tarka and T. Tolba and R. Tsang and K. Twelker and J. -L. Vuilleumier and A. Waite and J. Walton and T. Walton and M. Weber and L. J. Wen and U. Wichoski and J. Wood and L. Yang and Y. -R. Yen and O. Ya. Zeldovich},
journal= {arXiv preprint arXiv:1512.06835},
year = {2016}
}
备注
Published in JCAP, 29 pages, 13 figures