Speaker
Description
Non-destructive beam instrumentation is an essential tool for accelerator operation, and a number of beam instrumentation techniques exist. However, conventional techniques are designed for bunches of $10^9-10^{11}$ particles, and lack the precision required to characterize low-intensity ($10^4-10^6$) muon bunches. Instrumentation for this regime is required for the development and operation of a muon ionization cooling demonstrator. A new instrumentation scheme is proposed, leveraging AC-LGAD sensor technology to develop a minimally destructive beam velocity monitor for low-intensity semi-relativistic muon bunches. This is the first beam monitoring system to use in-beam silicon sensors for bunch-by-bunch snapshots with picosecond precision. Bunch timing is reconstructed from a series of precision clock phases that digitally record discriminator signals from the pixel array. Timing information from multiple spaced planes is used to determine mean bunch momentum. Pileup is addressed by using time-over-threshold information to drop pixels which see multiple hits. Detailed simulation of a 25μm-pixel detector scheme in a muon cooling demonstrator reconstructs the momentum of low-intensity muon bunches to within 1% of its true value, and meets the precision requirement for setting up the beamline. Bunch-by-bunch momentum reconstruction in a proposed demonstrator, which has a 704 MHz repetition rate, would require fast discriminators, currently in development. Thus, current and emerging sensor technology would be adapted for a novel, in-beam momentum monitor to provide essential per-bunch feedback to the operation of next-generation muon accelerators.