In-medium modifications of the $\pi \pi$ interaction in photon-induced reactions

J. G. Messchendorp, S. Janssen, M. Kotulla +19

Differential cross sections of the reactions $(\gamma ,{\pi }^{\circ }{\pi }^{\circ })$ and $(\gamma ,{\pi }^{\circ }{\pi }^{+}+{\pi }^{\circ }{\pi }^{-})$ have been measured for several nuclei (${}^1$H,${}^{12}$C, and ${}^{\mathrm{nat}}$Pb) at an i…