Yes — there have been a few measurements and discussions of temperature effects in CosmicWatch-style scintillator/SiPM muon detectors, though not many formal dedicated studies.
The main effect is usually not the plastic scintillator itself, but the SiPM gain drift with temperature.
Key findings:
- The CosmicWatch detector uses a SensL SiPM whose breakdown voltage changes with temperature by about 21.5 mV/°C. With fixed bias voltage, this changes gain and therefore trigger efficiency.
- One recent analysis found roughly a 4.4% gain variation over an 11.7 °C detector temperature range. They observed detector temperature correlated with apparent muon rate at r = +0.49. After correcting for detector temperature, most of the apparent atmospheric-temperature correlation disappeared.
- The newer CosmicWatch v3 documentation explicitly mentions logging temperature so corrections for “temperature-dependent gain shifts” can be applied, although the correction is apparently not yet implemented in firmware/software.
- Another portable scintillator coincidence detector study found little dependence of coincidence count rate on modest temperature changes, while noting that single-channel SiPM rates are more temperature-sensitive.
Practically, for CosmicWatch detectors:
- Single detector count rates can drift noticeably with temperature because threshold crossing depends on SiPM gain.
- Coincidence setups are much more stable.
- The scintillator light yield itself changes only weakly over normal room/outdoor temperatures.
- Most temperature dependence comes from:
- SiPM gain
- dark count rate
- discriminator threshold interaction
Typical magnitude:
- Roughly a few percent over ~10 °C is plausible for uncorrected systems.
If you are doing precision muon flux work with your coincidence setup, useful approaches are:
- log onboard temperature continuously
- keep detector temperature stable
- use coincidence triggering
- or implement active bias compensation:
Vbias(T) = V0 + k(T – T0)
where k is about +21.5 mV/°C for the SensL device.
The original and the paper The Physics Behind the CosmicWatch Desktop Muon Detectors discuss atmospheric studies but only lightly touch on thermal effects.