On the Stability of Rapidity Gap Analysis.pdf

On the Stability of Rapidity Gap Analysis Liao Hongbo Wu Yuanfang 2 Institute of Particle Physics, Huazhong Normal University, Wuhan 430079 China 0 0 2 n u J 0 2 1 Abstract v 4 It is argued that the newly introduced moments of rapidity gaps for the event 8 1 byevent fluctuations depends on the number of events and multiplicity. The interesting 6 0 2 ones of them are unstable under ISR energies of hh collisions. The instability get well 0 / improved when multiplicity increases. h p - p e h : v i X r a In recent decade, the eventbyevent fluctuations become more and more impor tant in multiparticle production and relativistic heavy ion collisions. This is partly due to the fact that the large local multiplicity fluctuations have been observed in all kind of col lisions [1] and that the appearance of new state of matter, Quark Gluon Plasma (QGP), predicted by QCD, will definitely associate with large energy density fluctuations [2]. How to measure the fluctuations turn to be a powerful tool in probing the QGP phase transition. However, in the market at present, there is no good suggested measure for the purpose. In order to measure first the eventbyevent fluctuations of low multiplicity samples, such as those in hh collisions under ISR energies, R.C.Hwa and Q.Zhang newly introduced the rapidity gap analysis [4] after a long exploration for the end [5]. Though it has been used to analyze experimental data [3], the efficiency of the method for low energies of hh collisions has not been seriously checked. In this letter, we are going to study the efficiency of the method. The rapidity gap is defined by the difference of rapidity of two neighbor particles in an event, x = X − X ,