Channeling measurements have been performed to investigate the annealing of the irradiation damage produced in monocrystalline silicon by low dose (1012-1013ions cm−2) implants at 40 K with monatomic and diatomic ions of As, Sb, Te and Bi having incident energies of 15–30 keV. The mass of the bombarding ion has a pronounced effect upon the subsequent annealing behaviour, with the heavier ion implants annealing at the higher temperature. Within the monatomic series of implants, the annealing behaviour correlates well with the average deposited energy densitywithin the cascade. However, thiscorrelation fails to account for the observed increase in anneal temperature in going from monatomic Bi to diatomic Sb2or Te2implants.