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- Production status
- pilot production has been QAed . No major problems were found and Lidia is most likely executing production now.
- expect St-W muDst to be ready in few days.
- identified problems to be fixed before next production
- explain why PPV sees no tracks crossing TPC CM
- why 7-bit bXing has no abort gap for the fill on page 19 top plot ?
- ETOW absolute calibration to compensate for incorrect TCD phase used during data taking. Two alternative methods are used:
- Justin is comparing ratio of slopes for correct & incorrect TCD phase from regular minB events from pp200 data: http://drupal.star.bnl.gov/STAR/blog/stevens4/2009/aug/05/run-9-eemc-tcd-phase-and-effective-gains
Fig 1.1 show example for 1 tower
Link http://drupal.star.bnl.gov/STAR/system/files/ETOW_SlopeSet0vSet1234.pdf
shows slopes (top) and the deduced gain correction (bottom) for all towers and all crates. - Scott is analyzing slopes from calibration pp500 data taken and various TCD phases and predicts similar gain correction for the TCD phase value used during W-data taking.
The comparison is here
In particular pages 4-6 show error bars. Both methods lead to the same gain correction.PDF name scott-08-20-2009-all_ETOW-crates.pdf - The plan is to compute weighted average gain correction and upload it to DB with a different flavor. So user will get non-sense gains for the default 'ofl' and needs to request those. (Very good plan, Jan)
- Justin is comparing ratio of slopes for correct & incorrect TCD phase from regular minB events from pp200 data: http://drupal.star.bnl.gov/STAR/blog/stevens4/2009/aug/05/run-9-eemc-tcd-phase-and-effective-gains
- Status of Vernier scan was presented by Ross: http://drupal.star.bnl.gov/STAR/blog/rcorliss/2009/aug/20/absolute-cross-section-notes-5
The rate of STAR events vs. time is described by the product of 2D gauss functions representing spread of ions in both beams. We know relative displacement of both beams for every time period from Angelika. Ross fits 2 params: sigX, sigY - the width of gauss.
Fig 3 ('counts vs. steps') shows anticipated result. The value of 'skfNN' is absolute cross section of STAR BHT3 trigger in units TBD and assuming no hot tower correction is needed.
Ross add constant background to better describe rate , yet still peaks are under-predicted.
He will continue to try to model vernier scan better and is awaiting for muDst from 6 runs from ongoing production to be able to assess how stable is value of skfNN. - run QA : Hal will do QA of the first week of pp500 data within next 30 days, backward in time.
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