Speaker
Description
The electromagnetic (EMCal) and hadronic (HCal) calorimeters for the sPHENIX experiment will use ~120,000 Silicon Photo-Multipliers (SiPMs) as optical sensors (Hamamatsu S12572-33-015P). SiPMs are small, immune to magnetic field, low bias voltage, high gain devices, but are also sensitive to radiation damage, particularly to neutrons. Moreover, one EMCal tower will be read out by four SiPMs, whose performance characteristics, including gain versus operating voltage have to be closely matched. We have performed irradiation tests with gamma rays up to 1 Mrad and neutron exposures up to $10^{12}{\mbox{cm}}^{-2}$, with a continuous neutron spectrum up to 17 MeV, and studied the dark current, breakdown voltage and gain curve as a function of integrated dosage. We also designed and constructed an SiPM testing device that measures the breakdown voltage and gain curve with the SPS (single photon spectrum) method. This testing device will serve as the prototype for three large scale devices that will be used to characterize and group all ~120k SiPMs for the sPHENIX EMCal and HCal detector before final assembly. In this poster we will report on the results of our irradiation tests and the performance of the prototype test device used to characterize the 1800 SiPMs being used for the sPHENIX preproduction calorimeter prototypes being assembled in 2018.
| Content type | Experiment |
|---|---|
| Collaboration | sPHENIX |
| Centralised submission by Collaboration | Presenter name already specified |
