Photon sandwich detectors with WLS fiber readout

摘要

A photon detector for BNL experiment E949 is described. The detector consists of a lead scintillator "sandwich" of 25 layers of 5 mm thick scintillator BC404 and 24 layers of 2 mm lead absorber. Readout is implemented with 30-60 cm long wavelength shifting (WLS) fibers (BCF 99-29AA) glued into grooves in the BC404. Average yield was measured with cosmic rays to be about 43 p.e./MeV. Performance of extruded plastic scintillation counters developed for sandwich detectors of photons for the KOPIO experiment are also described. For a 7 min thick counter with 4.3 m long WLS fibers spaced at 7 mm, a light yield of 18.7 p.e./MeV and time resolution of 0.71 ns were obtained. A prototype photon veto module consisting of 10 layers of 7 mm thick extruded plastic slabs interleaved with I mm lead sheets was tested. (C) 2002 Elsevier Science B.V. All rights reserved. References: 4