BEXCO - Room F(201/202/203/204)
[CRI205] A study about effect of background light on the gain of Photomultiplier Tubes
Photomultiplier Tubes (PMT) is mostly used in air Cherenkov light detection in extensive air shower of cosmic rays. The Cherenkov telescopes work at clear and moonless nights, therefore it is susceptible to the background of stars in the sky. Because Earth’s rotation and revolution, the night-sky background (NSB) would changes a lot at different seasons and even at one night. In this case, we conducted an experiment to evaluate the impact of NSB to the gain of PMTs; moreover, this affect can be reduced by optimizing the dividers of PMTs.