Investigations on enhancement in track revelation sensitivity of allyl diglycol carbonate (CR-39) due to laser treatment

Abstract

It is shown that for 6 MeV a-particles, the track revelation sensitivity is higher in the polymer of allyl diglycol carbonate (CR-39) treated with a CO₂ laser beam at 25 J/cm². With increasing etching time the sensitivity of the laser treated CR-39 increases relative to that of the untreated polymer and for an etching time of about 10 h it becomes twice that of the untreated polymer. The bulk etch rate of about 200 μm/h has been estimated at the surface of the laser treated CR-39 and it decreases very rapidly with the time of etching. The track etch rate is also found to be very large in the treated CR-39 and it decreases in the laser affected region as the etching progresses. At the same depth in the polymer sheet, sensitivity of the treated CR-39 is only slightly larger than that of the untreated polymer. Laser induced structural transformation explains most of the observed effects. Laser treatment is shown to increase the sensitivity without reducing the resolution of the polymeric track detector.