Transverse momentum dependent decorrelation in Pb-Pb collisions at LHC
Abstract
Based on A Multi-Phase Transport (AMPT) model simulations, the transverse momentum dependent decorrelation has been studied in Pb-Pb collisions at sNN= 2.76 and 5.02 TeV, respectively. It has been found that the mix-order factorization ratio rm, n value deviates significantly from unity in noncentral collisions. Such effect becomes stronger with an increase in the pT difference pTa-pTb. These decorrelations are not only between the same order harmonic but also between the different order harmonic, which as a result of the initial fluctuations appear between the different phase spaces. It has also been found that the correlations involving higher powers of the flow vector yield stronger decorrelation, rm|n;3<rm|n;2<rm|n;1~(m=2,3; n=2,3,4,5), except for the weighted factorization ratio r3|4;k. The breaking phenomenon of these factorization ratios indicated that it provides a possible observation for studying the initial fluctuation properties of heavy-ion collisions.