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PDT’s. First, the PDT Status. Readout All 6 crates in global run. x39 & x34 frequently stop due to MFC related Front End errors. 85/94 PDT’s are in the global runs. Infrastructure & Electronics during access 3 FEB’s replaced (MW + TM + HH)
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PDT’s First, the PDT Status • Readout • All 6 crates in global run. x39 & x34 frequently stop due to MFC related Front End errors. • 85/94 PDT’s are in the global runs. • Infrastructure & Electronics during access • 3 FEB’s replaced (MW + TM + HH) • HV work on PDT 113/213 to jumper out a broken wire until Oct. shutdown. (MW + TM) • Reprogram of B&C-layer cobo’s Completed (HH)
Timing Trigger = Minbias*ticksel 0 OLD Timing Plots First crossing after synch gap (d.t.=550 ns) • We have made adjustments to move the hits a little earlier (reducing t0’s). • T0’s are available for All PDT’s • For 67/94 I have measured T0’s from timing distributions. For the others I made an estimate based on the t0’s of similar PDTs. • Three timing sets used so far • We haven’t looked at Pads yet - unpacking problems.
PDT’s • Example of T0’s from run 130080
PDT Problem • Mujet triggers provide sample of relatively clean high-pT muons. Sooo… where are the tracks? • I used D0ev to identify the first event (14th in the file) that satisfied the mujet trigger. I used the save event button to extract it. • I used dsdump --raw --byteswap to display the contents of the event (~200000 lines). • I hand-unpacked and hand event-displayed There were nice hits in B & C layer PDT’s that corresponded with the scintillator hits. • Onne Peters ran the muon code and made an event display picture of that event too.
Event Display Picture • Then • Onne disabled hit selection and made the event display picture again.
Summary/Plans • Central Muon ID suddenly will achieve higher efficiency. • Short Term proposed plan for muons • select and tapout dimuon event-tuples • initially these will be |eta|>~1 • hopefully within a week or so Reco will have a fix for central muons, too. • Use these to study performance and develop W and Z to muon object identification • I believe the events will be primarily b-bbar with non-isolated muons until we use isolation. Probably we should start where we were in Run I: • delta R (mu-jet) > 0.7 for 0.5 cone jets • good idea to check Run I publications • I recall W/Z and top had slightly different criteria
Conclusions • We believe PDT’s are operating well. • Starting to put shine on the electronics. • Kill hot cells • fix missing channels. • We’ve got t0’s for all runs taken since April 27th and a set of timing parameters which will set them to an average of 100 ns. • We have identified a change in software which will make it possible to find tracks in the PDT’s. • A quick scan appears to show some electronics has been cables backwards. • Next step: hand scan 500 tracks.
Central Muon during October Shutdown • Scintillators • The major task is an SFE cycle to correct a time-of-flight gate mistake. • PDT’s • A-layer access to • Reprogram timing chips on Cobo’s • Replace a couple Cobo’s and FEB’s to suppress hot or missing channels • Rewire FEB<-->Cobo connections in Oct 1. • Broken wires • ~10 PDT’s have had broken wires jumpered out. • Procedure to fix the wire involves pumping and refilling with operating gas. So we ill need a Bob Kubinsky or other expert to assist with that.
Central Muon during October Shutdown • PDT’s continued • Survey • The Run II position of some unsurveyed PDT’s is known to no better than 1” from Run I data. Implication is (Dp)/p ~ 300% instead of ~20% in those directions. • It’s important to complete the muon survey!
