The study of medium modications of hadrons embedded in hadronic matter is aimed at understanding the origin of hadron masses in the context of spontaneous chiral symmetry breaking in QCD and its partial restoration in a hadronic environment. So far experiments have been focused on the light quark sector. The high-intensity p beam of up to 15 GeV/c will allow an extension of this program to the charm sector both for hadrons with hidden and open charm. The in-medium masses of these states are expected to be affected primarily by the gluon condensate.
Another study which can be carried out in PANDA is the measurement of J/ψ and D meson production cross sections in p annihilation on a series of nuclear targets. The comparison of the resonant J/ψ yield obtained from p annihilation on protons and different nuclear targets allows to deduce the J/ψ -nucleus dissociation cross section, a fundamental parameter to understand J/ψ suppression in relativistic heavy ion collisions interpreted as a signal for quark-gluon plasma formation.