One-to-one correlation of fission tracks between zircon and mica detectors

Neutron-induced fission tracks in zircon were correlated one-to-one with those in mica detectors. Track counting efficiency in zircon was about 0.75 times that in mica even though tracks in zircon were isotropically counted. The tracks which were found only in mica were remarkably short (less than 4 μm) in comparison with other tracks having counterparts in zircon. An unetchable range of about 2.0 μm was found in each end of a fission track in zircon. The lower counting efficiency in zircon was attributed to the higher registration threshold required to produce an etchable track in zircon.