Talks

• Profiling and timing studies : Han Do

• Very high energy electron filter results : Ulla Blumenschein
• Plots were shown based on the special run - 150490. The first showed the pt spectrum for the leading L3Electron clusters from the EM_HI trigger which were marked and passed : with no cuts, EM fraction > 0.9 and EM fraction + shower width cuts. The L3 rate with respect to the L1 rate was presented as a function of a Pt min cut. At 40 GeV this was around 3.7 % dropping down to 0.7% at 50 Gev. The corresponding rejection plot was also shown.

• Tracking update : Daniel Whiteson
• Daniel showed results of trying to match L3 tracks to electrons in a Z->ee sample selected using calorimeter information and a di-EM mass cut. The matching rate was around 50%. There is the suggestion of structure in the phi distribution of the matching rate but the statistics are a little low. Plotting the ratio of the calorimeter energy measurement and the track Pt measurement gives a peak at one as expected. There seem to be a significant number of tracks for which stereo hits were not found. Daniel scanned a few events where this seemed to be the case by eye and in those events there are clearly layers of the CFT where there are no stereo hits. An update on the tracking error studies was presented. There has been no progress made on the elestic fitting pulls. It would require a major rewrite of the code to get the pulls correct. Daniel has tuned the existing parametrized hit errors to get the pulls to be close to one.

Discussion Items

• Muon certification : Martin Wegner
• Martin showed some of the plots he showed at the trigger board meeting on the 13th and we discused some of the points raised during that meeting. It was decided it would be very useful to see the rejection and efficiencies with respect to the appropriate L2 triggers. Martin showed us the Pt resolutions of offline, L3 and L2 muons. While recent changes - specifically using the survey geometry - have brought the resolutions for L3 and offline into line there is still a discrepancy with respect to L2. A possibility is that because the central reconstruction efficiency for tight muons is bad (and not well understood) both that the resolution is dominated by loose muons - where the resolution is expected to be worse.

Scribe: Jon Hays.