Calibration of fission track dating parameters

Abstract

A comparison of fission track and K-Ar ages for a set of mineral age standards has been used to evaluate the ²³⁸U spontaneous fission decay constant, ²³⁸λ_f. Neutron doses were monitored with two fission-track glasses calibrated against a series of Co wire neutron flux monitors in an irradiation facility with a uniform flux distribution in the Herald reactor. An interlaboratory comparison shows that these calibrations compare closely with standard dose measurements made at the U.S. National Bureau of Standards. A value of (7·±0·28) × 10^-17 yr^-1 was obtained for ²³⁸λ_f.