IBIC2026 - 15th International Beam Instrumentation Conference

New intra-bunch feedback system in J-PARC Main Ring

TUP010

1 Sept 2026, 16:20

2h

Ballroom C (Whistler Conference Centre)

Poster Presentation MC06: Feedback Systems and Beam Stability Tuesday Poster Session 2

Speaker

Daiki Nagao (High Energy Accelerator Research Organization)

Description

The J-PARC Main Ring (MR) is being upgraded toward a beam power of 1.3 MW. As the beam intensity increases, higher-frequency intrabunch oscillations are expected to become more pronounced. To suppress these oscillations, the intrabunch feedback (IBFB) system is being upgraded.
The current IBFB system operates at a sampling rate of approximately 110$~$MS/s synchronized with the circulating beam. The upgraded system increases the sampling rate to 576$~$MS/s. As a consequence, the sampling clock is no longer synchronized with the beam revolution frequency. Therefore, the differentiated signal from beam position monitor is integrated over each RF period, where the integration timing is dynamically updated to follow the varying RF period during beam acceleration.
The upgraded IBFB system is currently under evaluation. This poster presents the results of beam tests in the non-acceleration region and simulation studies under beam acceleration.