Passage of fission fragments through thin film plastic scintillators

Abstract

The slowing down of fission fragments from the spontaneous fission of 252Cf has been studied in the self-supporting thin films of plastic scintillator NE 102A, using a surface barrier detector. The measured residual energies and hence the energy losses of the mean light and heavy fragments after passing through the thin films of thickness ranging from ∼-100 to 1200 μg/cm 2 of NE 102A are reported. These measurements were carried down to 20.0 MeV and ∼- 14.0 MeV for light and heavy fragments respectively. The shape spectrum parameters from the slowed spectra are determined. The measured energy straggling parameters obtained from these spectra show a maximum around 300 μg/cm 2 of NE 102A and the energy bunching effect due to fission fragments is observed in thicker plastic scintillator films (>300 μg/cm 2). The stopping power obtained from these measurements is compared with the theoretical predictions.