Particle identification performance of the prototype Aerogel RICH counter for the Belle II experiment
S. Iwata, I. Adachi, K. Hara, T. Iijima, H. Ikeda, H. Kakuno, H. Kawai, T. Kawasaki, S. Korpar, P. Krizan, T. Kumita, S. Nishida, S. Ogawa, R. Pestotnik, L. Šan… 展开作者
S. Iwata, I. Adachi, K. Hara, T. Iijima, H. Ikeda, H. Kakuno, H. Kawai, T. Kawasaki, S. Korpar, P. Krizan, T. Kumita, S. Nishida, S. Ogawa, R. Pestotnik, L. Šantelj, A. Seljak, M. Tabata, E. Tahirović, Y. Yusa
备注：
20 pages, 22 figures, To be published in Prog. Theor. Exp. Phys
We have developed a new type of particle identification device, called an Aerogel Ring Imaging Cherenkov (ARICH) counter, for the Belle II experiment. It uses silica aerogel tiles as Cherenkov radiators. For detection of Cherenkov photons, Hybrid Avalanche Photo-Detectors (HAPDs) are used. The designed HAPD has a high sensitivity to single photons under a strong magnetic field. We have confirmed that the HAPD provides high efficiency for single-photon detection even after exposure to neutron and gamma-ray radiation that exceeds the levels expected in the 10-year Belle II operation. In order to confirm the basic performance of the ARICH counter system, we carried out a beam test at the DESY using a prototype of the ARICH counter with six HAPD modules. The results are in agreement with our expectations and confirm the suitability of the ARICH counter for the Belle II experiment. Based on the in-beam performance of the device, we expect that the identification efficiency at 3.5 GeV/c is 97.4% and 4.9% for pions and kaons, respectively. This paper summarizes the development of the HAPD for the ARICH and the evaluation of the performance of the prototype ARICH counter built with the final design components.
Institute of Particle and Nuclear Studies, KEK（高能加速器研究机构粒子核研究部）；Alikhanyan National Science Laboratory（阿里卡尼扬国家科学实验室）；Universite Paris-Saclay, CNRS/IN2P3, IJCLab（巴黎-萨克雷大学）；Jožef Stefan Institute（约热普·施特凡研究所）；Faculty of Mathematics and Physics, University of Ljubljana（卢布尔雅那大学）；University of Naples "Federico II" and INFN（那不勒斯费德里科二世大学）；Faculty of Chemistry and Chemical Technology, University of Maribor（马里博尔大学）；Tokyo Metropolitan University（东京都立大学）；Chiba University（千叶大学）；Toho University（东邦大学）；Nagoya University（名古屋大学）；Kitasato University（北里大学）；Niigata University（新潟大学）；The Graduate University for Advanced Studies (Sokendai)（综合研究大学院大学）
Belle II探测器前方区域开发了新型气凝胶RICH计数器，用于有效分离不同粒子，覆盖0.5至4 GeV/c的动量范围，并成功采集了600/fb的数据。
The Construction and Commissioning of the Belle II iTOP Counter
桶区粒子识别探测器对于扩展在SuperKEKB加速器上运行的Belle II实验的物理范围至关重要。为此，研制了一种新型的环形成像切伦科夫探测器--成像传播时间计数器。iTOP由16个独立的模块组成，围绕光束线方位角排列。每个模块由石英制成的光学元件（一个反射镜，一个棱镜和两个棒），微通道板光电倍增管（MCP-PMT）阵列和前端电子器件组成。固件处理读出的波形，并将产生的脉冲高度和命中时间发送到Belle II数据采集系统。2016年夏天，探测器的建造和安装完成，此后探测器一直在调试。本演讲介绍Belle II iTOP计数器的构造和调试。
