Borexino实验中的缪子和宇宙成因中子探测
仪器与探测器
2015-03-17 v2 天体物理仪器与方法
摘要
Borexino是位于LNGS的一个液体闪烁体探测器，旨在探测来自太阳、超新星、核反应堆和地球的中微子和反中微子。这些信号的微弱性质要求将低于几MeV的本底进行强烈抑制。所有探测器组件极低的内在放射成因污染需要辅以对缪子和缪子诱导本底的有效识别。缪子在其穿过探测器的轨迹上通过散裂过程产生不稳定核素，其衰变可能模拟预期的信号；对于半衰期超过几秒的同位素，由缪子相关反符合引起的死时间会变得不可接受地长，除非其应用可以限制在沿缪子轨迹的子体积内。因此，不仅要以非常高的效率识别缪子，还要精确重建它们的径迹，这对实验的物理计划至关重要。Borexino内部探测器被一个外部水切伦科夫探测器包围，后者在完成这项任务中起着基础性作用。描述了探测器的设计原理及其实现。回顾了用于识别缪子的策略并评估了其效率。发现整体缪子反符合效率为99.992%或更高。介绍了开发的专用径迹重建算法。其性能针对已知方向的缪子事件进行了测试，例如来自CNGS中微子束流的事件、来自专用外部缪子径迹器的测试径迹以及其角分布反映当地上覆岩层轮廓的宇宙线缪子。所达到的角分辨率为3-5度，横向分辨率为35-50厘米，具体取决于穿越缪子的碰撞参数。还介绍了用于高效标记宇宙成因中子的方法。
引用
@article{arxiv.1101.3101,
title = {Muon and Cosmogenic Neutron Detection in Borexino},
author = {Borexino Collaboration and G. Bellini and J. Benziger and D. Bick and S. Bonetti and M. Buizza Avanzini and B. Caccianiga and L. Cadonati and F. Calaprice and C. Carraro and A. Chavarria and A. Chepurnov and D. D'Angelo and S. Davini and A. Derbin and A. Etenko and F. von Feilitzsch and K. Fomenko and D. Franco and C. Galbiati and S. Gazzana and C. Ghiano and M. Giammarchi and M. Goeger-Neff and A. Goretti and E. Guardincerri and S. Hardy and Aldo Ianni and Andrea Ianni and M. Joyce and V. Kobychev and Y. Koshio and D. Korablev and G. Korga and D. Kryn and M. Laubenstein and C. Lendvai and T. Lewke and E. Litvinovich and B. Loer and F. Lombardi and P. Lombardi and L. Ludhova and I. Machulin and S. Manecki and W. Maneschg and G. Manuzio and Q. Meindl and E. Meroni and L. Miramonti and M. Misiaszek and D. Montanari and V. Muratova and L. Oberauer and M. Obolensky and F. Ortica and M. Pallavicini and L. Papp and L. Perasso and S. Perasso and A. Pocar and R. S. Raghavan and G. Ranucci and A. Razeto and A. Re and A. Romani and D. Rountree and A. Sabelnikov and R. Saldanha and C. Salvo and S. Schönert and H. Simgen and M. Skorokhvatov and O. Smirnov and A. Sotnikov and S. Sukhotin and Y. Suvorov and R. Tartaglia and G. Testera and D. Vignaud and R. B. Vogelaar and J. Winter and M. Wojcik and A. Wright and M. Wurm and J. Xu and O. Zaimidoroga and S. Zavatarelli and G. Zuzel},
journal= {arXiv preprint arXiv:1101.3101},
year = {2015}
}
备注
42 pages. 32 figures on 37 files. Uses JINST.cls. 1 auxiliary file (defines.tex) with TEX macros. submitted to Journal of Instrumentation