A direct measurement of the distribution in depth of 26Al in the Estacado meteorite

Abstract The two-dimensional distribution of 26 Al across a slice of the Estacado meteorite was measured using non-destructive γ-γ coincidence counting. The maximum activity was found to be 60 ± 2 dpm kg −1 and the variation across the slice rather small. The intensity and distribution are in moderate agreement with existing theoretical models if the pre-atmospheric shape of the meteorite had been a sphere of radius 0.35 ± 0.05 m , but it was more likely to have been slightly non-spherical.