A First look at Gain vs. High Voltage
-south PMT's only. The group starting at 1900V(top) are the Burle and the group starting at 2000V(bottom) are the XP2020.
fit for S18 gives G = 6.2184x10^-27 * V^8.6169, solving for V for the appropriate G (Channel no.) will give the correct voltage to use. (approximately :/ )