We have investigated the low-energy (0-10 eV) electron attachment on C 60 and C 70 , using an improved energy resolution close to zero incident energy (0.030-0.060 eV). We have found evidence of a zero-energy attachment process (within 0.030 eV), for both C 60 and C 70 , indicating that a s-wave capture process is present at low energy for these two molecules. For C 60 , although in contrast with symmetry arguments, and with previous free-electron attachment experiments, this result is in full agreement with the conclusions presented by several groups, using the Rydberg atom energy transfer technique to investigate the low-energy attachment in these systems. Energy positions of several resonant states, appearing between 0.5 and 5 eV in the ion yield versus electron energy spectrum, are clearly established in C 60 and C 70 , and assignments are discussed. Lifetime measurements are reported for the fullerene anions. In the incident energy range 7-11 eV the lifetime τ of C − 60 was found to vary from 500 to 45 µs, respectively, in agreement with previous measurements. The thermionic model for C − 60 detachment does not seem to describe the values obtained, and their observed variation in this energy range. The lifetime of C − 70 is longer and could not be measured precisely with our time-of-flight conditions. An estimation of τ ≈ 700 µs has been made at E i = 11 eV. Below E i = 7 eV the lifetime of C − 60 was larger than 700 µs and could not be measured precisely.

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