Hi Dieter Thanks a lot for the comments, > very interesting data! a few comments: > > On Fri, 5 Jul 2002, Claus O. E. Jorgensen wrote: > > > > - (h++h-)/2 pt spectra for 0-5, 5-10, 10-20 and ~40-60% centrality at > > eta=0. > > I guess we also have identified pions (up to pt=2???). We could have a > comparison between charged hadrons and pions. I'm working on that. > > - pt ratio (R) of central (0-10) to semi-peripheral (~40-60). Here I > > conlude that we our measurements indicate a suppression of high pt > > particles when comparing central to semi-peripheral collisions - this > > comparison is of course independent on fit ranges and reference data > > taken with another experiment. > > is this shown on the your second figure? Then I do not understand the last > plot (R vs pt ofr 40-60%). It's not there - I'll put it on the web-page soon. > > - ratios of spectra to p+pbar reference (ua1) data. These ratios are > > dependent on the choice of reference data and fit ranges/methods. > > However, suppression of high pt hadrons is observed and it is more > > pronounced for the central collisions. > > Here we should follow the PHENIX and STAR method: > use R_AA (and the pp parametrization) as defined in > http://www.phenix.bnl.gov/phenix/WWW/info/physpub/003/prl/PRL88_022301.pdf > or > http://www.star.bnl.gov/STAR/sds_l/papers/journals/p2002/highpt.pdf > > > > > - ratios of protons to all hadrons as function of pt. Mesonic vs. baryonic > > jets??? Who knows about this stuff? Is my result reasonalbe (I just > > pulled out the numbers)? > > That's nice. Can you plot protons over mesons (all-protons)? > look at http://arXiv.org/PS_cache/hep-ph/pdf/0108/0108045.pdf That a nice reference to have (thanks). I'll work more on these ratios. > > > > - pi- spectrum at y approx 2.2 for 0-15% central. The statistics are > > unfortunately not good enough to make qualitative statements on the > > slope at high pt. > > > > As Ian suggested, you can chose a coarser binning for high pt. > There is no slope at high pt, the spectrum should follow a power law - > and it does. > > > > - pi- pt ratios of central (0-10) to semi-peripheral (~40-60). The ratio > > constant (within the erros). What do we expect at forward rapidities? > > What puzzles me is that the ratio is flat at low pt. At high pt we > might expect a flat ratio (or even increasing) due to an interplay between > initital multiple scattering (Cronin) and/or jet quenching and/or > whatever. So far this plot has been made by merging the raw pt spectra for all the settings. The assumption is that the corrections are the same in the two centrality ranges and therefore cancel out. I'll try to make the plot with corrections. Cheers, Claus
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