1. 1 SiPM Gain Test SiPM Multiple APD pixels operating at Geiger mode. Output is the sum of the outputs from all APD pixels. Advantages Compact size High Gain( 10E5 ~ 10E6) Low Bias Voltage(15~70V) Insensitive to Magnetic Field Challenges Temperature sensitive. Hamamatu SiPM samples

2. 2 Setup for gain measurement Hamamatsu SiPMs( 3 models.) S10362-11-0XXC, XX = 25, 50, 100 Effective area 1x1mm2 25um(1600), 50um(400), 100um(100) Light tight box Apply Bias Voltage( ~70V) Use Preamplifier MITEQ, Gain(30dB), 1-500MHz Waveform readout by TDC6154 40(20)GS/s Varying threshold( 5mV ~50mV with 5mV step) 1500 events at each threshold.

3. 3 Test Setup Preamp(MITEQ) Bias Voltage Power for Preamp Output LED SiPM Placed inside a light-shield box.

4. 4 SiPM with 25um pixel( 1600pixels) Gain Estimation : 2x10E5 ( 2.75x10E5 from spec.) Assuming preamp gain = 30.

5. 5 SiPM with 50um pixel( 400pixels) Estimated gain = 6.2x10E5 ( 7.49X10E5 from the spec)

6. 6 SiPM with 100um pixel( 100pixels) Estimated gain = 1.1x10E6 ( 2.41X10E6 from the spec)

7. 7 Plans Couple a SiPM to Crystal. Optical glue or grease. Expose to Radiation Source. Array of SiPM to Crystal (Block). Support & holding structure. Individual Bias voltage adjustment.