Effective mass distributions for protons, pions and kaons particle combinations (two and three hadrons) for Au-Au reactions at 200 AGeV center of mass energy

A preliminary analysis of the effective mass distributions for two and three hadronic combinations including protons, pions and kaons is presented for a number of 798,000 Au-Au reactions at 200 AGeV center of mass energy collected by the BRAHMS Collaboration (RHIC-Brookhaven National Laboratory). Different procedures to detect the classical resonances inside the high level of background were used. Comparisons with simulations of experimental data using UrQMD code are given, too. The strong suppression of the hadronic resonances weights (delta resonance, N*, K*, rho, etc.) could suggest a possible quark-gluon state. (authors)