A fiber detector radiation hardness test

An intense 146 MeV/c pion beam was stopped inside a scintillating fiber detector made out of 12 planes with 16 pixels each, where every pixel consists of 8×8 densely packed scintillating fibers of 500 μm diameter. The detector was irradiated for 52 h to more than 10 kGy at its center. Before and directly after the irradiation the detector had been exposed to a particle beam to compare the corresponding light output. This study was continued during the following three months using cosmic rays. No damage was found taking into account the measurement errors of 5–10%. A 9 cm deep lucite degrader became irreversibly non-transparent in the irradiation region.