Effective reaction threshold for heavy-ion collisions

A new interpretation of the experimental results of Gauvin, Le Beyec, Lefort, and Deprun published recently in Phys. Rev. Letters is given. The calculation of effective thresholds in a dynamical classical model for the reactions ⁴⁰Ar on ¹⁶⁴Dy and ⁸⁴Kr on ⁷²Ge and ¹¹⁶Cd gives 139, 149.5, and 212 MeV to be compared with the experimental values of 135, 147, and 204 MeV.