Stella:
Radium calibration:
Lead lines a bit annoying --> Gain drift callibration with gold instead
Small gold bars on muon veto
Calibration measurement with lead (and gold on muon veto)
µU measurements:
80's data and our data match, but their calculations seem to be better than the quick ones Natalia did
Pi0 term which they don't explain --> From dimension analysis it seems to be deca-hexapole deformation which doesn't require symmetry breaking (suggestion Thomas)
I went digging after the meeting and it is indeed decay-hexapole deformation. I send some papers to Stella that could be interesting. (Michael)
Michael:
Fitting for integrals:
gold (2p1/2-1s); barium (2p1/2-1s and 2p3/2-1s); chromium (2p-1s doublet in one fit); potassium (2p-1s doublet in one fit)
Upper limit for barium DoD: Estimate background at peaks; integrate in [-2sigma, 2sigma]. 95% confidence peak integral < 1.96 sqrt(integrated background)
Calibration source Ag-108m (t1/2 = 250d):
10+ useable lines (7 within 100 keV from K 2p-1s); No silver Compton edge expected around the 2p-1s peak
Slightly annoying 707 keV peak --> Assuming sigma = 1 keV (last year we had 0.8), it seems alright
Emilio will do a test next week and send over a spectrum --> Michael will follow up on this
Katharina:
Quadratic calibration of the SDD detector
~8 eV precision, limited by the calibration --> No zero-point shift or covariance matrix used, so uncertainty could likely be even better (Suggestion Thomas and Michael)
New custom box from Slovakia works very well: With long and old cables it got similar resolution as the old system in optimal conditions