Abstract

• A change of fission track density and track length in Makrofol with different annealing temperature and annealing time was investigated. Ten pieces of (1 cm x 1 cm) Makrofol detectors each was contacted with 252 Cf source for 1 hour. Among them, two pieces were unannealed. Four pieces of Makrofol with fission tracks were annealed at 60 C and the other four pieces were annealed at 100C for 30 min, 60 min, 90 min and 120 min respectively. After that the annealed and unannealed detectors were etched in 6.25N NaOH at 60C for 75 min. The fission fragment tracks were counted and the tracks length were measured with the aid of an optical microscope. The average tracks densities of detector were calculated at different temperature and various time. It was found that the tracks length and tack density decrease with the increasing of annealing time and annealing temperature.