Measurements and simulations of Cherenkov light in lead fluoride crystals

Institut für Kernphysik, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
Nuclear Instruments and Methods in Physics Research Section A Accelerators Spectrometers Detectors and Associated Equipment (Impact Factor: 1.32). 09/2001; 465(2-3):318-328. DOI: 10.1016/S0168-9002(01)00668-4
Source: arXiv

ABSTRACT The anticipated use of more than 1000 lead fluoride (PbF2) crystals as a fast and compact Cherenkov calorimeter material in a parity violation experiment at MAMI stimulated the investigation of the light yield (LY) of these crystals. The number of photoelectrons (p.e.) per MeV deposited energy has been determined with a hybrid photomultiplier tube (HPMT). In response to radioactive sources a LY between 1.7 and was measured with 4% statistical and 5% systematic error. The LY optimization with appropriate wrappings and couplings was investigated by means of the HPMT. Furthermore, a fast Monte Carlo simulation based on the GEANT code was employed to calculate the characteristics of Cherenkov light in the PbF2 crystals. The computing time was reduced by a factor of 50 compared to the regular photon tracking method by implementing detection probabilities as a three-dimensional look-up table. For a single crystal a LY of was calculated. The corresponding detector response to electrons between 10 and was highly linear with a variation smaller than 1%.

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