rolling bhabha calibration issues

quick recap, status in April

-last rolling calibration finished on April, 7th
-some technical problems due to Root based spatial/temporal db communication, not a problem of the bhabha calibration code! - fixed by Andy Salnikov
-calibration on a very promising way
-between April, 7th and the shutdown, only 2.3e6 bhabhas accumulated, calibration not started
-with startup, accumulated events would have been useless - asked for finishing the calibration with these events

rolling bhabha calibration results - some information and statistics

-PC people didn't want to use a modified release in PC --> extracted and saved temporal db content into ROOT some files
-Loaded it into a private Cdb and finish the calibration with a modified release (reduced the threashold to 2.3e6 bhabhas)
-release 21.1.1a and 50 events of run 72624 --> 2 bhabha events
-calibration successful: 5 channels with not enough hits, 4 known from previous calibration, one just below the cut
-dead channels: 22:43, 32:87, 40:63 known, 5:27-29, 6:35 new, but were dead/masked in run 72624
-some non validated channels, all in theta ring 56
-All crates stored, nothing unusual, everything fine

rolling bhabha calibration results - comparison plots

-comparison difficult, because:
-accumulation of bhabhas done on base of Feb constants - we didn't load the April 23rd constants before the shutdown
-but calculated relative constants multiplied to the last rolling constants (Apr, 7th)
-basically, relative constants were multiplied to Feb constants twice
-first comparison: new rolling bhabha constants vs. April, 23rd offline calibration
-expectation: relative constant between both = relative constant of last offline calibration (0.9991)



-relative constant 0.9984, looks not too bad...
-second comparison: new rolling bhabha constants vs. Feb constants
-expectation: relative constant between both = (relative constant of last offline)^2 (=0.9982)



-relative constant 0.9977, also not too bad...
-third comparison: new rolling bhabha constants vs. April, 23rd offline calibration* (multiplied the relative constants twice)



-absolute difference 0.6 &permil
-result looks reasonable, some differences because the constants are not the same, of course!
-results cannot take into account the differences in the source calibration constants!!!
-nevertheless: very good aggreement :-)

rolling bhabha calibration is on a very very promising way