What pions can tell us about the neutron skin of nuclei

We use the Isospin Quantum Molecular Dynamics approach to analyse the isospin ratios of pion production in collisions of heavy ions at incident energies below 2 AGeV. It is found that the comparison of the centrality dependence at different energies allows to gain information on the neutron skin of the nuclei, but also on other ingredients like the nuclear equation of state of asymmetric matter.