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92 A FIRST APPENDIX
trons than a standard PMT with bialkali photocathode [42]. The collaboration
reported in [55] the resolution of a 8x8x30 cm 3 (8x8x23 cm 3 )
crystal coupled to two PMTs (9269A from Electron Tube Ldt., PbCs photocathode,
quartz window) as 3.5 % (4.6 %) RMS at 662 keV with a photoelectron
yield of 5.6 (4.5) pe/keV. Kim et al. [43] report further resolution
(RMS at 662 keV) ranging from 4.0 to 5.6 % of crystal with a length
of 30 cm and front and rear surfaces ranging from 55x55 to 70x70 cm 2 ,
using two 3-in Pmts (ET D726UK).
Renker [60] reported energy resolutions of scintillation detectors with
APD for LSO crystals of 12.1 % FWHM, 22.4 % FWHM for BGO at
511 keV and 4.3 % FWHM with YAP:Ce crystals at 662 keV.
Ikagawa et al. [61] CsI:Tl 10x10x10 mm 3 with Hamamatsu APD S8664-
1010N (10x10 mm 2 ) reached 4.9 % FWHM at 662 keV in comparison
with 5.9 % (FWHM at 662 keV) with the PMT R7899EG (Hamamatsu,
1 inch diameter). 28 primary pe/keV were produced in APD. Ikagawa
et al. [61] reported that APD can efficiently detect weak scintillation
light of big crystals, even if the scintillator and APD size do not match.
They couple an APD via a light guide to the rear face of a 48x3x300 mm 3
big BGO plate and reached a energy resolution of 20.9 % (FWHM at
662 keV and -20 ◦ ) in comparison to 7.1 % (FWHM at 662 keV and -20 ◦ )
for a 10x10x10 mm APD and an equal APD. At room temperature (20 ◦ )
the APD readout of the small BGO crystals showed a resolution of 8.3 %
and 10.4 % for the PMT readout (FWHM at 662 keV). Asano et al. [62]
CWO crystal (5x5x5 mm 3 ) with APD (Hamamatsu S8664-55, 5x5 mm 2 )
and Hamamatsu PMT (R6231HA). Best results were obtained at -30 ◦ C
with 6.4 and 7.0 % (FWHM at 662 keV). At 20 ◦ the APD and PMT had
resolutions of around 9.2 and 7.6 % (FWHM at 662 keV).