Radiation Damage Effects on Silicon Photomultipliers for CMS Detector Studied
Researchers tested Hamamatsu Silicon Photomultipliers (SiPMs) with various cell sizes after exposure to reactor neutron radiation up to 2×10^14 n/cm² to assess their durability for the CMS MIP Timing Detector. The study measured how neutron irradiation affects key device parameters including breakdown voltage, signal amplitude, dark current, and noise. Understanding radiation damage in SiPMs is critical for designing reliable particle detectors in high-energy physics experiments that operate in intense radiation environments.
Researchers at the CMS experiment conducted radiation damage studies on recently developed Hamamatsu Silicon Photomultipliers with cell sizes of 15, 20, 25, and 30 micrometers. The devices were irradiated with reactor neutrons at the Jožef Stefan Institute in Ljubljana up to a fluence of 2×10^14 n/cm² (1 MeV equivalent), simulating the harsh radiation environment of the Large Hadron Collider. Using pulsed light illumination, the team systematically characterized how neutron exposure affects critical performance parameters: breakdown voltage, signal amplitude, dark current, and noise characteristics. These measurements are essential for validating SiPM technology for the CMS MIP (Minimum Ionizing Particle) Timing Detector, which requires detectors that maintain functionality despite prolonged exposure to high-energy particle radiation. The findings will inform detector design decisions and operational parameters for future high-energy physics experiments.
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- arXiv physicsCenter
Radiation damage studies of silicon photomultipliers for the CMS MIP Timing Detector
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