Latest Results from Ceres/na45

Ceres/na45 Status Report

A New Robust Fitting Algorithm for Vertex Reconstruction in the Ceres Experiment

In this paper we report on the application of a robust approach based on a reweighted least squares method for the vertex reconstruction of the CERES/NA45 experiment at the CERN SPS for the case of 160 GeV/u Pb+Au collisions and compare its performance with the presently used algorithm based on the minimization of summed Gaussian weights. In the CERES/NA45 experiment a doublet of cylindrical si...

Electromagnetic Radiation and in - Medium Effects

The theory of thermal photon and dilepton emission from hot and dense hadronic matter, as well as from the Quark-Gluon Plasma, is reviewed in the context of extracting in-medium properties of the matter constituents. In phenomenological applications to ultrarelativistic heavy-ion collisions we focus on low transverse-momentum ”anomalies” as recently observed in photon and dilepton spectra by WA...

ar X iv : h ep - p h / 01 02 19 2 v 1 1 5 Fe b 20 01 1 Dileptons and photons from central heavy - ion collisions at CERN - SPS

A unique parameterization of secondary (thermal) dilepton and photon yields in heavy-ion experiments at CERN-SPS is proposed. Adding those thermal yields to background contributions the spectral shapes of the CERES/NA45, NA38, NA50, HELIOS/3 and WA98 data from experiments with lead and sulfur beams can be well described.

/ 97 03 44 0 v 1 2 7 M ar 1 99 7 Comment on : “ Search for direct photons from S - Au Collisions at 200 GeV / nucleon ” by the CERES Collaboration

In this note we comment on a recent publication in this journal by the CERES (NA45) Collaboration [1]. The authors report to have determined an upper limit on the direct photon yield relative to the decay photon yield in S + Au collisions of 14 % and 7 % by two different methods, respectively. We argue that these limits are unsupported by the results and analysis of the CERES data. The systemat...