Hi I think we all understand this is preliminary - just a few more comments - TPC calibrations I think that the pad-status and time-offsets can be done rather rarely, but the Vdrift should be done not according to run-number but to time say every 6 hour or so to catch the pressure changes. it would also be useful if the Vdrift cal from the monitors could be done for all runs. This would really tell when the tracking Vdrifts should be done. If this was part of the histograms gathered in the local-tracking step, it would be rather painless rather than running this independtly (Ramiro could you look at this). - TPC response i) I think the words "non-optimal" edge is putting on an positive spin; The effect persists for at least 5 cm. ii) I hope we can use the newer 'clustering and tracking that takes care of clusters near pad pads better. Since there is no easter/passover vacation here, this can (may) happen next week. - On Geometry - we hope that a survey of T5,T4 and T3 and be squeezed into the Mon-Wed opening but it is not guarenteed pp machine project have priority. I hope T2 can be added. - Keeping track on files; I will follow-up with Hiro and Bjoern to have the scheme of getting version numbers ,keeping file , run information available in a database , implemented so it can be used soon (probably not for v01) . - Policy In regard to the tpc calibrations I think it would be valuable if you could do first a) All dedicated zero field runs b) The 63 GeV data, which we may have a hope of analyzing on a faster scale than the bulk of the 200 GeV. Q: Does the break next week start wed afternoon or has it expanded in Denmark? ---------------------------------------------------------------- Flemming Videbaek Physics Department Brookhaven National Laboratory e-mail: videbaek@bnl.gov phone: 631-344-4106 ----- Original Message ----- From: Ian Bearden To: flemming videbaek Cc: devlist Sent: Friday, April 02, 2004 3:59 AM Subject: Re: [Brahms-dev-l] global tracking Hi all, Once again, part of the problem here is due to different understandings of the word PRELIMINARY, and a willing disregard of the VERSION 1 (i.e. alpha!!) of the "global" tracking files. I am redoing the time calibrations of the TPCs (including all instrumented rows in T2) which may help some of the problems. As for the edge effect on T1, I will try to look at this as soon as I get a few spare minutes (he said, looking forward to the Easter "vacation"). The situation, as I understand it, is *that the survey is only partially complete, but will be done next week. *the TPC calibrations for 9930 were for about 50 runs before, so should probably be done. *we do not understand the edge of the FFS very well (see FV's comments on T1, and Djamel's plots showing deltaX on H1), that is there are some "non-optimal" edge effects in BOTH T1 and T2. *the TPC calibrations have NOT been done systematically through out run04 yet. I will try to do this in the next week or so, starting from the beginning and calibrating every (approx.) 10 runs. Given this, together with what FV has written, I propose the following plan of attack: 1. I continue to work on TPC calibrations+tracking. I hope to have a helper (guess who, Truls!) who will arrive on Monday. 2. In parallel, DO continues to optimize calibrations for PID. I suppose our geom. problems will affect the number of tracks, but will not affect the general method we use. 3. We agree not to expect v01 to be of "final" quality :) 4. Krakow group works their geometry voodoo on the FS (I think this requires only "local" tracks, is that right Pawel?) Those of you who have some other issues to add, please do so now, so that we can get these problems solved AQAHP. Best regards, Ian On 2/4-2004, at 03:03, flemming videbaek wrote: Some comment to questions and plots shown by Djam earlier today. a) scalers trigger 6 (and others). A: the DAQ does not have a linear response with time, when the rates are high it may stop storing data on disk for a little while. This is certainly ok, since it is just a time-dependent deadtime. b) another problem is that for certain runs I have seen trigger 6 not being present - a NIM mosule was change late in the run. I suggest this gets moinbitore by having plots of N-trigger 6/sec vs beginning of run (not sequence) N-trigger-6 before LVL0 i.e triggerword 2 c) FFS dang -- the geometry of T1-T2 is unfortunately still un-resolved! The most recent survey confirmed the B values are close to correct. -- this certainly will reflect both matching and dang.. d) How often and how many Vdrift cal have been done? For the run 10286 I used today to check geometry there is clearly a significant difference i Vdrift of T1 and T2 at about 5%. the calibrate runs is not too far away. e) the projection to Bb vertex hides some real problems in FS tracking. As we know from the -au an pp run the projection to the vertex is no good when the tracks are close to the edge of T1. the plot Track vtx on BB plane hides this problem, but two facts are obvious i) there is an offset 3cm that is significant an ii) there is an X(T1) and/or angle difference ; I think we need a plot VTX-diff vs. theta FS that will show the problems clearly. f) D3-d4 momentum. The geometry for T5 has yet to be done properly. A survey is schedule for Monday-Wedn. Hopefully this will help resolve some of the differences. g)the fact that the dx-dy for T3-T4 does not show up at 0,0 points to a geometry issue. cheers Flemming ---------------------------------------------------------------- Flemming Videbaek Physics Department Brookhaven National Laboratory e-mail: videbaek@bnl.gov phone: 631-344-4106 _______________________________________________ Brahms-dev-l mailing list Brahms-dev-l@lists.bnl.gov http://lists.bnl.gov/mailman/listinfo/brahms-dev-l ------------------------------------------------------------------------------ _______________________________________________ Brahms-dev-l mailing list Brahms-dev-l@lists.bnl.gov http://lists.bnl.gov/mailman/listinfo/brahms-dev-l _______________________________________________ Brahms-dev-l mailing list Brahms-dev-l@lists.bnl.gov http://lists.bnl.gov/mailman/listinfo/brahms-dev-lReceived on Fri Apr 2 07:20:28 2004
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