BOOSTR: A Dataset for Accelerator Control Systems

The Booster Operation Optimization Sequential Time-series for Regression (BOOSTR) dataset was created to provide a cycle-by-cycle time series of readings and settings from instruments and controllable devices of the Booster, Fermilab’s Rapid-Cycling Synchrotron (RCS) operating at 15 Hz. BOOSTR provides a time series from 55 device readings and settings that pertain most directly to the high-precision regulation of the Booster’s gradient magnet power supply (GMPS). To our knowledge, this is one of the first well-documented datasets of accelerator device parameters made publicly available. We are releasing it in the hopes that it can be used to demonstrate aspects of artificial intelligence for advanced control systems, such as reinforcement learning and autonomous anomaly detection.

The machine protection system for CSNS

Background The China Spallation Neutron Source (CSNS) accelerator consists of an 80 MeV H- LINAC, a 1.6 GeV rapid cycling synchrotron (RCS) and two beam transport lines. The uncontrolled beam may permanently damage the components or lead to very high residual radiation dose along the beam line. So the equipment protection must be deliberately designed and implemented. Purpose The machine protection system (MPS) protects components from being damaged by the beam. The response time requirement for the CSNS MPS is less than 20 ms, so the PLC (programmable logic controller) was adopted to implement the interlock logic. Methods The MPS was implemented as a two-tier architecture system, and developed through utilizing PLC and Experimental Physics and Industrial Control System (EPICS) software toolkits. The application logic was taken into careful consideration during the implementation stage. An embedded CPU module can function as an IOC accessing PLC I/O modules through the sequence CPU, with an embedded Linux operation system. Results The interlock logic and heartbeat functions were tested with all functions ok. Time consumption has been measured thoroughly since the important requirement, which is around 15 ms to stop the beam. Conclusions MPS was completed in Sep. 2017 and then put into operation. It has been operating smoothly for more than 3 years. MPS has played an important role in every stage of CSNS’s commissioning and operation and achieved high reliability during the user’s experiment operation. The accelerator recently runs stably with low equipment failure.

Progress status in fabrication of HBC stripper foil for 3-GeV RCS at J-PARC in Tokai site

In the 3-GeV Rapid Cycling Synchrotron (RCS) at Japan Proton Accelerator Research Complex (J-PARC), we adopted thick Hybrid type Boron-doped Carbon (HBC) stripper foil for multi-turn H- charge-exchange injection. The HBC stripper foil developed at KEK has demonstrably improved the foil lifetime significantly. In addition, Graphite Thin Films (GTF) developed by KANEKA corp. was attempted to use for user operation. The GTF is a multilayer graphene sheet and it is expected to be a new candidate for highly durable charge stripping foil. HBC and GTF foils can be both employed the J-PARC RCS for long-term user operation. Early manufacturing of the stripper foil for the J-PARC was carried out according to the following two steps: foil fabrication at the KEK Tsukuba site and foil preparation at the JAEA Tokai site. Recently, the HBC foil deposition apparatus was relocated from KEK to JAEA, and new HBC foils were fabricated at the Tokai site. The performance of the new HBC foil was verified to be equivalent to the original HBC foil with offline beam irradiation tests. Furthermore, the use of the new HBC foils was successfully demonstrated during RCS user beam operation for one week.