Minutes of BRAHMS Analysis Meeting Friday 25 September 2009 =========================================================== Present: Kris, Flemming, JH, Ramiro, Challis, Steve, Michael Selemon and Casper sent email reports Agenda http://indico.cern.ch/conferenceDisplay.py?confId=68938 09:30 discussion on k/pi paper Ionut, Flemming A new version is made available by Ionut - some discussion systematic errors. - final figures ok. - other comments 09:50 recent discussion on ptopi paper Pawel Staszel 10:20 p + p stopping revisited Kris Hagel We started with Kris pp Stopping =========== Kris has taken NA49's 17GeV net proton dN/dxf distribution and transformed it to our beam energies. We then see that the transformed dN/dy distribution equals our data at 62 and 200GeV. This is equivalent to saying the dN/dXf is the same at the 3 energies. He is working on producing net baryons. This has some statistical problems since he is getting correction factors from Pythia. Currently he sees no lambda's in his simulation. (Note: This problem was solved by the end of the afternoon). k/pi Ionut: =========== We discussed the comparison between STARs photon yield at forward rapidity, which is 2*pi0 and our charged pions. They are significantly higher than ours at y=3.5. Also our <pT> is seems high for that bin. Notice we only include 20% of acceptance. Ionut estimates that the systematic error is at least 25%. Flemming suggests 30% and adding it to the figure. There was some discussion on the figures and slopes vs pbar/p. Michael suggested comparing NA49 slopes vs our as a function of y-ybeam. Recent discussion on ptopi paper: Pawel ======================================= There was a good discussion on the physics discussion in Pawel's paper. The coalesence models are best suited to mid-rapidity. Therminator has some advantages in this region and that is why we can do the comparison to this. Pawel had some concerns about weak decays. There was an animated discussion on the physics of quark coalescence, velocity fields and constituent vs valence quarks. There seemed to be a sense that we should drop the discussion of the velocity fields. Pawel will go over the text and update it, trying to address the concerns expressed today. He will also include a discussion of weak decays. CuCu: Selemon ============= Selemon was not at the meeting but sent a report. He has extracted dN/ dy and <pt> from individual fits to the pi,k,p spectra. He now has to update the tables and the text in the paper. d/p: Casper =========== Casper had planned to attend but got held up. He is running flemmings macro to develop lambda corrections for the proton spectra. He should have this done by next week. ================== Submitted by Michael Murray ======================== _______________________________________________ Brahms-l mailing list Brahms-l_at_lists.bnl.gov https://lists.bnl.gov/mailman/listinfo/brahms-lReceived on Fri Sep 25 2009 - 16:56:06 EDT
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