Ramero, JH, Ramero, Flemming Steve, Selemon, Michael Pawel and Natalia Hans from Oslo Kris Agenda http://indico.cern.ch/conferenceDisplay.py?confId=12060 Friday 02 February 2007 top 09:30 Updates on Rich vs Tof2 analysis (20') ( Slides ) Pawel Staszel 09:50 pp @ 62 GeV analysis (20') ( Slides ) natalia katrynska 10:10 Plots for the proceedings. (20') ( Slides ) Catalin Ristea (NBI) Main plots that I would like to use for the rapidity dependence of NMF in AuAu_at_200AGeV. 10:30 QM Proceedings figures (20') ( Slides ) Ionut Arsene (UiO) Strangeness in Au+Au at 62.4GeV Action Items: 1) Catalin and Ionot will produce drafts of QM06 posters by next Friday. 2) Please read and comment on Hans draft which is listed as "proceedings" on the meeting web page above. 3) Flemming has seen a first draft of QM proceedings from Ian, please comment on this after it is circulated. Pawel: He has found a run with good overlap between TOF and RICH PID. Requires same vertex requirement for both TOF and RICH and compes pi+e +mu from RICH to TOF. The ratio RICH/TOF is a maximum near 95% at 4GeV. Below this pions start to be suppressed because they are near threshold. Note above 4GeV he starts to have kaon contamination above 5GeV. He has not suceeded in getting rid of all kaons etc. At the moment things look pretty consistent. He suspsects that his TOF pion cuts are too wide. For RICH PID there is come electron contamination below 3.5GEV. This may be due to the fact that pions are losing efficiency. FV and Ramero did detailed studies on the RICH efficiency. It is dominated by the efficiency of the ring finding algorithm and poisson fluctuations in the number of photons/pion. (This was much easier with k,p since one does not have muon contamination). Flemming commented that most of our electrons are conversions from pi_0. (Beam pipe is 4% of a radiation length at 6 degrees). Light vector mesons LVM are probably not significant. At y=0 beam pipe is 0.3%). A fiducial cut on X does not change the TOF/RICH ratio. Flemming said that the RICH efficiency to identify a pion is 90-95%. The chance to find a ring radius 0 is 3%. The difference in these numbers is because the ring finder occasionally finds the wrong radius due to interactions in gas and foils etc. Pawel feels that this study is finished now. Catalin: QM poster proceedings. Nuclear modification factors for AuAu at 200GeV. "IDENTIFIED PARTICLE NUCLEAR MODIFICATION FACTORS AT RAPIDITY 2 - 3.8 IN AU+AU COLLISIONS AT 200 AGEV - h+/h- set the general level of the suppression (contain particle ratios) - differences between baryons/mesons - Raa Vs. eta different contributions add up into Raa (pp, auau) to make an overall flat NMF. - centrality dependence - less medium density at forward rapidities, surface emission " He has produced several plots, please have a look. To fit in the procceding he will probably concentrate on 3 rapidities. He has calcuated Raa, RCP and Reta for charged hadrons. Then shows identified spectra for pi+- and p+-. He would like to add other settings but FV said this should be left for the final publication. He found a technical problem with a the low pT edges of the acceptance. This was because certain vertex bins do not contribute to the very low Pt part of the spectra. Vertices that have no acceptance for a low Pt bin should not be included in the normalisation. Ionot:QM06 proceedings: Spectra at 62GeV He has a problem showing all his spectra and will have to show less data in the proceedings. He wants to show temperatures. For all particles he has used a fit in exponentials in Mt but the fit is bad near y=0. JH, fit with best function and then calculate <pt>. For dN/dy we have to show the same dN/dy as in our paper. Ionot says that he is using a different centrality than in the paper. He has ideas to reduce the errors on k/pi at forward angles. FV said that he should not do that for the proceedings. For k/pi vs pbar/p he should propagate pbar systematic errors. Natalia Katrynska: pp at 62GeV Invariant yield spectra for identified particles after applying RICH and ToF identification. Settings: 6A&B861, 2A&B1723, 3A&B1723; FV is also looking at the same data. (Note trigger corrections are very important) A particle at pt = 1 and y=3 as xf=0.3 . Note that for pbars you must create a pair, so we may not have enough energy to hit the trigger counters. Pawel suggests modifying the "spectral object" to reduce the statistical errors. Ramero and FV disagree. Natalie's next work is to add the 4degree data, applying RICH and TOF efficiency correction and produce net proton spectra. _______________________________________________ Brahms-l mailing list Brahms-l_at_lists.bnl.gov http://lists.bnl.gov/mailman/listinfo/brahms-lReceived on Fri Feb 02 2007 - 10:55:47 EST
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