Effect of quark spins to the hadron distributions for chiral magnetic wave in ultrarelativistic heavy-ion collisions

Abstract

Topological fluctuation of the gluon field in quantum chromodynamics modifies the vacuum structure, and causes various chiral anomalies. In the strong magnetic field generated by semi-central heavy-ion collisions, the axial and vector density fluctuations propagate along the external magnetic field, called the chiral magnetic wave. Up to now the investigation of the various chiral anomalies in heavy ion collisions has been focussed on the charge distribution in the transverse plane. However, this paper points out that the information on the charge distribution is not enough and the spin effect should also be taken into account. Considering the charge and spin distributions together, π ^± with spin 0 are not proper particle species to study the chiral anomalies, as the signal may be significantly suppressed as one of the constituent (anti)quarks should come from background to form the pseudoscalar states. It is, therefore, necessary to analyze explicitly the vector mesons with spin 1 (K ^*± (892)) and baryons with spin 3/2 (Δ⁺⁺(1232), Σ⁻ (1385) and Ω⁻). If the chiral anomaly effects exist, the elliptic flow parameter is expected to be larger for negative particles for each particle species.