Dark count measurements

We want to characterize the dark count rates of each of our individual SiPMs.

VUV SiPM 1821

On 17-11-2022 we recorded with a room temperature of 17 degrees Celcius. We took 20 times a set of 1000 waveforms and 1 set of 10,000 waveforms at a pressure of 7.4x10^-5 mbar. We also took two noise runs where after starting the run normally, the SiPM bias was turned off. We select single photo-electron peaks with a simple threshold argument, and compute the rate of all combined dark count data. This gives us a dark count rate of 1.4+-0.3 MHz.

This is a plot of the raw data. A simple peak-finding algorithm is used to find the peaks (indicated by the red dots). A baseline is fitted (orange) and subtracted to produce the bottom plot.

A histogram of all combined 30000 waveforms, where the rate for each waveform is calculated separately and based on the single pe pulses.

VIS SiPM 01

On 18-11-2022 we recorded with a room temperature of 18 degrees Celsius. We took 20 times a set of 1000 waveforms and 1 set of 10,000 waveforms at a pressure of 6.3x10^-5 mbar. We also took two noise runs and one run with the lamp turned on at 400nm and slightly opened slits. Note that the SiPM was in fact behind the sample holder and not directly exposed to any light from the lamp. We select single photo-electron peaks with a simple threshold argument, and compute the rate of all combined dark count data. This gives us a dark count rate of 3.0+-0.4 MHz.

This is a plot of the raw data. A simple peak-finding algorithm is used to find the peaks (indicated by the red dots). A baseline is fitted (orange) and subtracted to produce the bottom plot.

A histogram of all combined 30000 waveforms, where the rate for each waveform is calculated separately and based on the single pe pulses.