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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

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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.

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Test Setup

Preamp(MITEQ)

Bias VoltagePower for Preamp

Output

LEDSiPM

Placed inside a light-shield box.

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SiPM with 25um pixel( 1600pixels)

Gain Estimation : 2x10E5 ( 2.75x10E5 from spec.) Assuming preamp gain = 30.

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SiPM with 50um pixel( 400pixels)

Estimated gain = 6.2x10E5 ( 7.49X10E5 from the spec)

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SiPM with 100um pixel( 100pixels)

Estimated gain = 1.1x10E6 ( 2.41X10E6 from the spec)

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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.