<sup>129</sup> I and <sup>247</sup> Cm in meteorites constrain the last astrophysical source of solar r-process elements
Benoît Côté, Marius Eichler, Andrés Yagüe López, Nicole Vassh, Matthew R. Mumpower, Blanka Világos, Benjámin Soós, Almudena Arcones, T. M. Sprouse, Rebecca Surman, M. Pignatari, Mária Pető, Benjamin Wehmeyer, T. Rauscher, Maria Lugaro
Abstract
The origin of r-process elements Theoretical models predict that the synthesis of heavy elements by the rapid neutron capture process (r-process) occurs in extreme astrophysical environments such as neutron star mergers or some types of supernovae. Testing those predictions by comparing them with the isotopic record has been difficult. Côté et al. examined two r-process isotopes, iodine-129 and curium-247, both of which have half-lives of 15.6 million years. Therefore, their ratio remains constant even long after the nucleosynthesis event. The ratio of those isotopes at the time of Solar System formation is recorded in meteorites. Comparing this value with nuclear astrophysics calculations shows that the most likely source was moderately neutron-rich material ejected from a binary neutron star merger. Science , this issue p. 945