({S}^5\): The destruction of a bright dwarf galaxy as revealed by the chemistry of the Indus stellar stream

The recently discovered Indus stellar stream exhibits a diverse chemical signature compared to what is found for most other streams due to the abundances of two outlier stars, Indus\(\_\)0 and Indus\(\_\)13. Indus\(\_\)13, exhibits an extreme enhancement in rapid neutron-capture (\(r\)-)process elements with \(\mathrm{[Eu/Fe]} = +1.81\). It thus provides direct evidence of the accreted nature of \(r\)-process enhanced stars. In this paper we present a detailed chemical analysis of the neutron-capture elements in Indus\(\_\)13, revealing the star to be slightly actinide poor. The other outlier, Indus\(\_0\), displays a globular cluster-like signature with high N, Na, and Al abundances, while the rest of the Indus stars show abundances compatible with a dwarf galaxy origin. Hence, Indus\(\_0\) provides the first chemical evidence of a fully disrupted dwarf containing a globular cluster. We use the chemical signature of the Indus stars to discuss the nature of the stream progenitor which was likely a chemically evolved system, with a mass somewhere in the range from Ursa Minor to Fornax.