The BLAST Cherenkov detectors

We report on the design, construction, and operation of a large array of diffusely reflective aerogel Cherenkov detectors. They are part of the detector instrumentation of the Bates Large Acceptance Spectrometer Toroid (BLAST) at the MIT-Bates Linear Accelerator Center. The Cherenkov detectors are used for particle identification. They are able to discriminate between pions and electrons with momenta up to 700 MeV/c.