RADIATIVE COOLING OF C-60

We have studied the radiative cooling of negatively charged fullerene ions by following the thermionic emission as a function of time after injection into the heavy-ion storage ring ASTRID. It is argued that el ectron emission can be used as a calibrated thermometer to measure the cooling rate. For C-60(-) at similar to 1500 K the cooling correspond s to a radiation intensity of similar to 190 eV/s, which is 2 orders o f magnitude more than expected from infrared active vibrations.