Double-scattering mechanism of production of two ${\rho }^0$ mesons in ultraperipheral, ultrarelativistic heavy ion collisions

Abstract

We study, for the first time, differential distributions for two ${\rho }^0$ meson production in exclusive ultraperipheral, ultrarelativistic heavy ion collisions via a double-scattering mechanism. The calculations are done in the impact parameter space. The cross section for $\gamma A\to {\rho }^{0}A$ is parametrized based on an existing model. Smearing of ${\rho }^0$ masses is taken into account. The results of calculations for single and double-${\rho }^0$ production are compared to experimental data at the RHIC and LHC energies. The mechanism considered gives a significant contribution to the $AA\to AA{\pi }^{+}{\pi }^{-}{\pi }^{+}{\pi }^{-}$ reaction. Some observables related to charged pions are presented too. We compare results of our calculations with the STAR collaboration results for four charged pion production.

Comments: 6 pages, 6 figures, talk given by A. Szczurek at the European Physical Society Conference on High Energy Physics (EPS-HEP 2015), 22-29 July 2015, Vienna, Austria