Summary

Three aerogel Cerenkov counter prototypes (n=1.017) have been designed according to different light collection concepts, and the performances have been investigated using the test beam at KEK. Belle type provides best light collection efficiency although there is position dependence. Integration Cube behind the aerogel is found to be very effective to reduce the uniformity without much sacrifice of photon yields. Due to the diffusive property of the aerogel, optical mirror itself does not provide particular benefit in terms of light collection efficiency compared with the Integration Cube type for such non-imaging Cerenkov counters.

References

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