IceCube/ PMTs

PMT Screening @ -32C

We are measuring the PMT Gain, P/V ratio, noize rate etc in a freezer box under extremely low temperature environment down to -40C. The left figure shows an example. This is the ADC spectrum. One can clealy seen the single photo-electron peak. The blue shaded region shows the case when we put a diffuser on the UV LED light sources while the black dots correponds to the case when the LED illuminates only the central region of a PMT.

Last modified: Sun Nov 9 12:38:07 JST 2003