RAVE J183013.5-455510 equivalent-width measurements

There is no evidence of binarity for this object. At [Fe/H]=-3.57, this star has one of the lowest metallicities currently observed, with 18 measured abundances of neutron-capture elements.

The presence of Ba, La, and Ce abundances above the solar system r-process predictions suggests that there must have been a non-standard source of r-process elements operating at such low metallicities. One plausible explanation is that this enhancement originates from material ejected at unusually high velocities in a neutron star merger event. We also explore the possibility that the neutron-capture elements were produced during the evolution and explosion of a rotating massive star.