Lawrence Berkeley National Laboratory

It has been empirically observed that the dependence of J/psi and psi' production on nuclear mass number $A$ is very similar. This has been postulated to be due to the predominance of color octet pre-resonant states in charmonium production and absorption. Two new experiments, NA60 at CERN and HERA-B at DESY, will measure the chi_c A dependence for the first time. These measurements should shed new light on the charmonium production and absorption mechanisms.