Howdy Peter et al. Great work on the TPC calibrations. This is really useful and eases the analysis a lot. Flemming and I sat down today to look at what you've done. We just have a few comments/questions for you. 1. What do you mean with "Normalized average ADC"? Is it average integrated or max ADC from clusters, or ADCs at the sequence level? And normalized to what? 2. Cutting 4 pads on either end of each pad row seems somewhat harsh. By looking e.g. at TPC pedestals pads 2, 3, n-4 and n-3 are typically not that noisy. Often even pads 1 and n-2 are ok. Also, cutting pads 0-3 has implications for cluster/hit reconstruction from pads 4++. So effectively it may very well be that you cut into the acceptance of the TPCs by disabling the 4 outermost pads on either end. 3. Your limits for hot and cold pads seem ok. You clearly get rid of some pads that are not useful. 4. Your time correction as function of row number is very nice, but as has been shown earlier it is not the full picture. There is also some pad number dependence for the time correction. Do you envision probing this dependence also? 5. Just to make it sure, did you use v_drift = 1.8 cm/us in the TPCs when investigating the drift velocity? When a thorough survey of the detector setup has been done after the proton run one can really get the full picture of the drift velocity using the fibers. Best wishes from Jens Ivar Peter H. L. Christiansen wrote: > Hi brahmsers > > I tried to put together some plots and words to describe what has been > done with the TPC calibrations. There are also some guidelines on how to > get the software to do calibrations). > http://www.nbi.dk/~pchristi/BRAHMS/TPC/ > (The classes that do the calibrations can all be found in brat > (modules/calib/tpc)) > > Cheers > Peter > >
This archive was generated by hypermail 2b30 : Mon Dec 03 2001 - 18:33:20 EST