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arXiv · physics/0207033

Photon sandwich detectors with WLS fiber readout

O. Mineev·E. Garber·J. Frank·A. Ivashkin·S. Kettell·M. Khabibullin·Yu. Kudenko·K. Li·L. Littenberg·V. Mayatski·N. Yershov
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Abstract

A photon detector for BNL experiment E949 is described. The detector consists of 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 WLS fibers (BCF99-29AA) glued into grooves in the BC404. Average yield was measured with cosmic rays to be about 43 p.e./MeV. Extruded plastic scintillation counters developed for sandwich detectors of photons for the KOPIO experiment are also described. For a 7 mm 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 1 mm lead sheets was tested.

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O. Mineev, E. Garber, J. Frank, A. Ivashkin, S. Kettell, M. Khabibullin, Yu. Kudenko, K. Li, L. Littenberg, V. Mayatski, N. Yershov. 2002-07-09. Photon sandwich detectors with WLS fiber readout. https://doi.org/10.1016/s0168-9002(02)01493-6

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