JOURNAL OF LOW TEMPERATURE PHYSICS, v.209, no.5-6, pp.824 - 831
Sm-Nd chronometers use Sm-146 and Sm-147 to determine the ages of major events in the early Solar System. Their half-lives are the most important nuclear parameters determining the accuracy of chronometry. However, the Sm-146 half-life is not wellestablished: the published values differ by similar to 30%, which results in significant uncertainties in the Solar System timeline. We are re-measuring the half-lives of Sm-146 and Sm-147 using decay energy spectroscopy and metallic magnetic calorimeters to improve the accuracy of the Sm-Nd chronometers. We report recent experimental results from our first measurement of a Sm-147 source, as well as status and plans for experiments on Sm-146.