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PB: Did not repeat analysis, just looked at 100GeV e on axis, no big change, only change is that beam profile is smaller along Y direction and beam profile is better reproduced, but as expected it does not improve CAL results.
We sent an email about CalTransRms to beamlist yesterday with Johan, should have thought about it earlier, basically our beam is larger wrt to pencil beams through the LAT geometry and that explains the difference in CalTransRms, smaller for BT (edit by JB :100GeV em shower splash on several towers, using either the LAT or the CU06 geometry changes CalTransRms)
Energy profile and plots about Tkr1CORECH - Johan
JB: slide 2: I improved G4 simulation this week (geometry is now 8 layers and 12 comlumns with gaps), possibility to connect G4 stdalone sim to output of beamtest06 beamline sim.
slide 3: Comparison of G4 stdalone with simple beam (blue), same with beamtest06 particles (yellow), BT data (black), BT MC (red) for 5 and 10 GeV
comments: magical match from last week disappeared, all energy disappeared in gaps. Very good agreement with G4 stdalone + beamtest06 with BT MC (red and yellow). Excellent consistency check of what we are doing. From here different comments can be made:
- beamtest06 is doing its job
- adding material along beamline should shift the peak
- francesco suggest to work on beam line package to introduce extra photons
LL: these would be photons from interaction of the beam with collimators
BL: can wait for franz, but the idea of the discrepancy coming from the magnets can be ruled out from the beginning; if there was a problem with magnets it would creat a large asymmetry, there are several magnets located in many places, whatever contributes to magnet creates halo on one side of the beam, we have no hint that this is the case here. and we played with extra material along the line and this really changed the profile. extra material will not help solving discrepancy, in my opinion the only way is to change calibration constants
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