Development of timing read-back system for stable operation of J-PARC

J-PARCの安定した運用のためのタイミングリードバックシステムの開発

Yang, M.*; 上窪田 紀彦*; 佐藤 健一*; 菊澤 信宏 ; 田島 裕斗*

Yang, M.*; Kamikubota, Norihiko*; Sato, Kenichi*; Kikuzawa, Nobuhiro; Tajima, Yuto*

J-PARC加速器では独自にタイミングシステムを開発し2006年から運用してきた。その間、機器の故障により25Hzのトリガが抜けが疑われる事例が発生したが、頻度が数日に1回程度であったため数多くの疑わしい機器の中から原因となった機器を見つけるのは困難だった。このようなトリガ異常を監視する目的でTriggered Scalerモジュールを開発した。本報告では、本モジュールで検知したJ-PARC MRで発生したトリガ障害イベントの1つを紹介し、Triggered Scalerモジュールの導入,作業原理,性能,ファームウェアのアップグレードについて述べ、将来の計画について報告する。

Since 2006, the Japan Proton Accelerator Research Complex (J-PARC) timing system has been operated successfully. However, there were some unexpected trigger-failure events, typically missing trigger events, during the operation over 15 years. When a trigger-failure event occurred, it was often tough to find the one with the fault among many suspected modules. To solve the problem more easily, a unique device, triggered scaler, was developed for reading back accelerator signals. The performance of the module has been evaluated in 2018. In 2021, we measured and observed an LLRF signal as the first signal of the read-back system for beam operation. After firmware upgrades of the module, some customized timing read-back systems were developed, and successfully demonstrated as coping strategies for past trigger-failure events. In addition, a future plan to apply the read-back system to other facilities is discussed. More details are given in the paper.