The GALAH Survey: Chemically tagging the Fimbulthul stream to the
  globular cluster $\omega$ Centauri
  Using kinematics from Gaia and the large elemental abundance space of the
second data release of the GALAH survey, we identify two new members of the
Fimbulthul stellar stream, and chemically tag them to massive, multi-metallic
globular cluster $\omega$ Centauri. Recent analysis of the second data release
of Gaia had revealed the Fimbulthul stellar stream in the halo of the Milky
Way. It had been proposed that the stream is associated with the $\omega$
Centauri, but this proposition relied exclusively upon the kinematics and
metallicities of the stars to make the association. In this work, we find our
two new members of the stream to be metal-poor stars that are enhanced in
sodium and aluminium, typical of second population globular cluster stars, but
not otherwise seen in field stars. Furthermore, the stars share the s-process
abundance pattern seen in $\omega$ Centauri, which is rare in field stars.
Apart from one star within 1.5 deg of $\omega$ Centauri, we find no other stars
observed by GALAH spatially near $\omega$ Centauri or the Fimbulthul stream
that could be kinematically and chemically linked to the cluster. Chemically
tagging stars in the Fimbulthul stream to $\omega$ Centauri confirms the
earlier work, and further links this tidal feature in the Milky Way halo to
$\omega$ Centauri.
