Calibration coefficients for MUST2 telescopes were extracted from run_0118 (acquired during night from 13th to 14th of May). They are now located in the folder:
/home/e748/analysis/nptool/Projects/e744/Calibration/Energy/Calibration/Summary_run_0118
Based on the analysis of this run we realized that:
- T4_StripX had pedestal normalization issue (for MATE 1,3,5,7) and alpha peaks were enlarged or doubled.
- Pedestals used until today (23rd of May) were based on the pedestal measurement of the 28th of April !
Due to that, we remeasured the raw values of the pedestals today and compared them with the one used up to now.
The differences (in channels) between these two pedestal values for each telescope are plotted on the attached figure (X from 1-128 and Y after).
The drifts can be partially understood by the fact that the conditions evolved a lot during one month (cooling system temperature, etc).
For the online analysis, calibration of run_0118 (13/05) will be used but they somewhat lie in time between the two pedestal measurement (28/04 and 23/05).
However it is important right after the experiment to perform a new alpha calibration in conditions much closer to the measurement. |