Cr isotopic anomalies in the early solar system

Precise Cr isotopic measurements in inclusions of the Allende meteorite show widespread 54Cr anomalies. Together with titanium and calcium isotopic anomalies, 54Cr excesses argue in favor of the addition of a small amount of matter processed in a neutron rich statistical equilibrium. 53Cr isotopic effects have been shown to be related to the decay of 53Mn. It has been found also in a chondrite and in a differentiated object related to core formation in small planetary bodies. A chronological scheme is given for the history of these bodies in the early solar system: time scales involved do not exceed 25 M.y