A New U Doped Glass Certified By the European Commission for the Calibration of Fission-Track Dating

In this paper we present a new series of unirradiated and pre-irradiated uranium doped glass discs that were manufactured and characterized for use in fission-track analysis. They are issued as Nuclear Reference Material IRMM-540. The certified quantities are the uranium mass fraction [=13.9 mgxkg−1], the n(235U)/n(238U) amount ratio [=0.007277] and the thermal Maxwellian neutron fluence [=1.070x1019 m−2]. Additional information is given related to the nominal composition of the glass and its content of thorium and neutron absorbing elements, the uranium homogeneity between and within discs, the neutron fluence monitors, the parameters of the neutron spectrum in the irradiation facility, the thermal stability of the fission tracks in the glass and the properties of the mica that has been used as external detector in contact with the irradiated discs.