Dear friends At the well attended conference at Ecole Polytechnique I presented the preliminary BRAHMS results. You will have found the power point version of my talk on the HEHI homepage at NBI wwww.nbi.dk/~hehi since tuesday. There was a significant interst for our results, particularly at 200GeV, namely the factthat we can show multiplicity distributions vs centrality and pbar/p data at forward angles. A pity we could not show the latter a midrapidity also. The other experiments showed very little. Star and Phenix nothing from 200GeV. Phobos only the eta=0t mult. value for central collisions. Thus we were at the front of the line -for a change. It is clear to me that we must proceed ASAP with a publication on the multiplicity. It will not take PHOBOS long to reach the same stage - if they haven't already in the last few days. I have had several discussions with Dima Kharzeev, E. Levin and others. I can see that the perspective of the paper must be on an issue of current central interest: saturation of the gluon related multiplicity. Dima has agreed to be a discussion partner on these issues, so we can draw on him. I think that a main thrust of the physics discussion must be to discrimunate between the soft+Hard version and the saturation picture. In that context it seems as if in particular the --- 200 GeV can be an improtant diagnostic for discriminating between these effects. The mult. wouldscale faster with energy if there is no saturation (Ncoll goes up) than if there is saturation (Ncoll - gluons) has set in. Thus I propose that we in addition to the figures that Steve and I discussed 2 weeks ago, also prepare a figure showing the ratio of multiplicities for the various centralities for the two energies. Another related picture is the mult. per participant pair vs. Npart for the various rapidities. Here agian we could take pairwise the ratio of these curves. In summary I believe we have a unique window of opportunity to come first with some important 200GeV physics- which we should not drop on the floor. I have not heard what the latest developments in refinig the multiplicity data are - perhaps due to the loss of my emails of this week. I woulod be happy to write the draft of the physics/discussion section as soon as the afore mentioned plots are available. Steve could you give us an update of where things stand. ? I am presently at CERN, and in better email contact again - although this hotel connection is not great. best regards JJ
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