CR-39 for Nuclear Particle Track Detection
The thermoset polymer, CR-39, is used in nuclear particle tracing and calorimetry as a solid state nuclear track detector (SSNTD). When a high energy particle impacts the polymer it breaks bonds and allows for preferential etching during post-exposure processing. These etched tracks can then be observed and characterized under a microscope.
CR-39 is sensitive to many particles such as energetic protons, alpha-particles and heavier ions, and fast neutrons. Thermal/epithermal neutrons can be detected by doping CR-39 with boron to produce the 10B(n,a)7Li reaction and subsequent alpha-particle detection.
This SSNTD has a wide variety of applications of radiation measurement, including home radon detection, dosimetry, and is a less visceral display of radiation damage for educators.
Click here for more information for best practice for the use of CR-39.
5.5 MeV alpha particles striking the CR-39 from various angles.
5.5 MeV alpha particles with energies moderated by passing through aerogel.
Alpha particles striking CR-39 through a large aperture.
Overexposure of CR-39 to alpha particles.