Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Procedures for the use of Lexan and Makrofol SSNTDs in the detection of environmental concentrations of 235U and 239Pu

Thesis/Dissertation ·
DOI:https://doi.org/10.2172/451232· OSTI ID:451232
 [1]
  1. Univ. of Utah, Salt Lake City, UT (United States)
Solid State Nuclear Track Detectors are used to study a variety of atomic particles. Polycarbonate SSNTD is used to study environmental concentrations of 235U and 239Pu in human urine and feces through fission track analysis. The samples of interest are deposited upon a Lexan slide, covered with a piece of Makrofol and exposed to a neutron fluence of 1.1 X 1017. The fissile isotopes in the sample fission and the resulting fission fragments pass through either the surface of the Lexan or the surface of the Makrofol. The positive Coulombic attraction of the ionized fission fragments causes the electrons of the polycarbonate lattice to move towards the path of these particles, resulting in the breakage of chemical bonds in the lattice. The detector is then chemically etched in 6.5 N KOH that preferentially dissolves the damaged polycarbonate left in the path of the fission fragment. The chemically etched fission tracks are permanent records of the path of the fission fragment. The etched fission tracks in Lexan are optically counted using a microscope and the fission tracks in Makrofol are counted using a Spark Chamber. The amount of fissile material in the original sample can be calculated from the number of fission tracks. This paper presents further details of procedures for etching fission tracks in Lexan and Makrofol and for operating a Spark Chamber to count etched fission tracks in Makrofol. The physics of fission track formation in dielectric detectors is also discussed, as well as the physics of the Spark Chamber.
Research Organization:
Utah Univ., Salt Lake City, UT (United States). Dept. of Mechanical Engineering
Sponsoring Organization:
USDOE
DOE Contract Number:
FC08-89NV10865
OSTI ID:
451232
Report Number(s):
DOE/NV/10865--T7; ON: DE97003783
Country of Publication:
United States
Language:
English