Mechanoluminescence by impulsive deformation of γ-irradiated Er-doped CaF2 crystals

► Impulsive technique has been used for mechanoluminescence (ML) studies in γ-irradiated Er doped CaF2 crystals. ► ML intensity exhibited two peaks with time (Im1 and Im2), where the intensity of both the peaks increased with increasing impact velocity. ► The time of occurrence of the peaks (tm1 and tm2) reduced with increasing the impact velocity. ► Total ML intensity (ITotal) first increases and then attains a saturation value with an increment in the impact velocity. ► A theoretical explanation is presented to the observed results.