$B Front End Electronics
$B>e$X(B: Test Results
$BLa$k(B: Comparison of Counter Configurations
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
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.
 T. Iijima et al., Nucl. Instr. and Meth. A 453 (2000) 321.
 S.K. Sahu et al., Nucl. Instr. and Meth. A 384 (1997) 544.
 I. Adachi et al., Nucl. Instr. and Meth. A 355 (1995) 390.
 R. Enomoto et al., Nucl. Instr. and Meth. A 382 (1996) 441.