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arXiv · 2408.16184

Development and Implementation of Advanced Beam Diagnostic and Abort Systems in SuperKEKB

Abstract

The SuperKEKB/Belle II experiment aims to collect high-statistics data of B meson pairs to explore new physics beyond the Standard Model (SM). SuperKEKB, an upgraded version of the KEKB accelerator, has achieved a world-record luminosity of $4.71 \times 10^{34} \, \mathrm{cm^{-2}s^{-1}}$ in 2022 but continues to strive for higher luminosities. One of the major obstacles is Sudden Beam Loss (SBL) events, which cause substantial beam losses and damage to the Belle~II detector. To find a hint for addressing SBL challenges, advanced beam diagnostic systems and enhanced beam abort systems have been developed. The diagnostic system aims to accurately pinpoint the start of beam losses, while the upgraded abort system quickly disposes of anomalous beams to minimize damage. This paper details the development and implementation of these systems, including high-speed loss monitors, time synchronization with the White Rabbit system, and data acquisition systems. Efforts to understand the mechanisms of SBL events, using acoustic sensors to detect discharges, are also discussed. These measures aim to improve the operational stability and luminosity of SuperKEKB, contributing to the experiment's success.

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BibTeXRIS

Keisuke Yoshihara, Tetsuro Abe, Michele Aversano, Alexander Gale, Hitomi Ikeda, Hiroshi Kaji, Hidekazu Kakuno, Taichiro Koga, Toru Iijima, Shinnosuke Kato, Ami Kusudo, Yuxin Liu, Akane Maeda, Sayan Mitra, Gaku Mitsuka, Kenkichi Miyabayashi, Isamu Nakamura, Hiroyuki Nakayama, Yu Nakazawa, Riku Nomaru, Iori Okada, Xiao-Dong Shi, Shuji Tanaka, Kenta Uno, Yutaka Ushiroda, Bela Urbschat, Rui Zhang. 2024-09-25. Development and Implementation of Advanced Beam Diagnostic and Abort Systems in SuperKEKB. https://doi.org/10.1016/j.nima.2024.170117

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