Contextual Info: ULTRA-LARGE-AREA SILICON DETECTORS AND PSDs HAMAMATSU PRODUCT BULLETIN PB-162 June 1988 Ultra-large-area silicon detectors made of full 4” wafer For energy measurements of cosmic rays and other high energy particles H am am atsu has d e v e lo p e d and p ro d u ce d u ltra -la rg e -a re a s ilic o n d e te cto rs m ade of fu ll size of 4 " w afers.