Positron annihilation spectroscopy is used to study the recovery behav
iour in electron irradiated In. A long component of 270 ps in the as-i
rradiated samples has been attributed to monovacancies produced during
the irradiation, which anneal out at 100 K to give rise to dislocatio
n loops. The results obtained are compared with previous works perform
ed in low temperature deformed In, concluding that the plastic deforma
tion in In is mainly due to twinning.