Efficiency calibration in the lab

Detector: GEM1800 - 90 deg
Source: 210Pb
Distance: 167.5mm
Start time: 9:58:00 - 30.04.2021
Stop time:  10:01:09 - 30.04.2021

file name: e127b_run0005.lmd
avrg. rate: 50Hz
dead-time:  1%

Still rate peaks, probably the ESR kicker or some other external influence. 
So we have double triggers occasionally. This might slightly affect deadtime determination.