Shock-induced luminescence in polymethylmethacrylate

Light emission during impact events is common and may be produced by various processes. These include the compression of gas between impactor and target, fractoemission and bulk luminescence. In this paper the results of a series of experiments on polymethyl methacrylate (PMMA) are presented. The relative intensity of emissions in the near infrared and visible regions have been measured and spectra obtained. Bulk luminescence is shown to be relatively weak at pressures of up to 22.5 GPa compared to fractoemission from the PMMA during release. At the maximum pressure used, 22.5 GPa, the relative intensity of the outputs of the photodiodes suggests a polymer temperature over 2000 K. The integration of the light emitted during the shock compression can be fitted to a black body giving an estimated temperature of 3700±400 K.