Double-scattering mechanism of production of two $ρ^0$ 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.