The Gaia-ESO Survey: Discovery of a spatially extended low-mass population in the Vela OB2 association

Understand

The nearby (distance~350-400 pc), rich Vela OB2 association, includes $\gamma^2$ Velorum, one of the most massive binaries in the solar neighbourhood and an excellent laboratory for investigating the formation and early evolution of young clusters.

• Recent Gaia-ESO survey observations have led to the discovery of two kinematically distinct populations in the young (10-15 Myr) cluster immediately surrounding $\gamma^2$ Velorum.
• Here we analyse the results of Gaia-ESO survey observations of NGC 2547, a 35 Myr cluster located two degrees south of $\gamma^2$ Velorum.
• The radial velocity distribution of lithium-rich pre-main sequence stars shows a secondary population that is kinematically distinct from and younger than NGC 2547.