High-resolution, low-latency, bunch-by-bunch feedback systems for nanobeam production and stabilization

Conference item

High-precision intra-bunch-train beam orbit feedback correction systems have been developed and tested in the ATF2 beamline of the Accelerator Test Facility at the High Energy Accelerator Research Organization in Japan. Two systems are presented: 1) The vertical position of the bunch measured at two beam stripline position monitors (BPMs) is used to calculate a pair of kicks which are applied to the next bunch using two upstream kickers, thereby correcting both the vertical position and trajectory angle. This system was optimized so as to stabilize the beam offset at the feedback BPMs to better than 350 nm, yielding a local trajectory angle correction to within 250 nrad. Measurements with a beam size monitor at the focal point (IP) demonstrate that reducing the trajectory jitter of the beam by a factor of 4 also reduces the observed wakefield-induced increase in the measured beam size as a function of beam charge by a factor of c. 1.6. 2) High-resolution cavity BPMs were used to provide local beam stabilization in the IP region. The BPMs were demonstrated to achieve an operational resolution of ~20 nm. With the application of single-BPM and two-BPM feedback, beam stabilization of below 50 nm and 41 nm respectively has been achieved with a closed-loop latency of 232 ns.

Authors: Burrows, P; Bett, DR; Blaskovic Kraljevic, N; Et al.

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: JACoW Publishing, Geneva, Switzerland
• Pages: 458-465
• Publication date: 2021-10-10
• Acceptance date: 2021-09-28
• Event title: 10th International Beam Instrumentation Conference (IBIC 2021)
• Event location: Virtual event.
• Event website: https://accelconf.web.cern.ch/ibic2021/
• Event start date: 2021-09-13
• Event end date: 2021-09-17
• DOI: 10.18429/JACoW-IBIC2021-THOB02
• EISSN: 2673-5350
• EISBN: 978-3-95450-230-1
• Language: English
• Keywords: FFR