CsI(Tl) scintillation detector with SiPM readout. Crystal size 12*12*25 mm = 3.6 cm3, Nice resolution of 6.5%@662 keV measured using Atom Nano Pro electronics ans Cs137 source from the side opposite to SiPM.
For best results use with 29.5 Volts bias. Excellent gain - at least 2 nC of charge per MeV of dissipated energy with 29.5 V bias voltage.

General scintillator properties:
ParameterUnitValue
Max. Emission Wavelengthnm550
Average Light Decay Timens900
Average Light Yieldphotons/MeV60000
Densityg/cm34.51
Effective atomic numberZ54
Crystal sizemm / cm310*10*30 / 3
Energy rangekeV10-3000 min.

Want to build a portable and very sensitive gamma spectrometer - it's your chance!
Check out my other lots, I hope you will find something interesting!
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