Pre-main sequence population of Sco-Cen unveiled with Gaia DR2
  We use Gaia DR2 data to isolate the pre-main sequence population
corresponding to the Scorpius-Lupus-Centaurus-Crux area on the sky making use
the Hertzsprung-Russell diagram. A sample of $120\,911$ sources was selected
with galactic coordinates $285^\circ\leq\ell\leq360^\circ$ and $-10^\circ\leq
b\leq+32^\circ$, and parallaxes between $5$ and $12$~mas where the relative
uncertainty in parallax was restricted to be $<10\%$. The pre-main sequence
sources were isolated due to a clear separation between the pre-main and main
sequences, well above the expected $0.75$ magnitude from a possible observed
population of equal mass binaries. The final sample contains $14\,459$ young
stellar objects. The traditional boundaries of the Sco OB2 association are well
traced by clear concentrations of young stars where the Upper Scorpius region
stands out as the densest concentration. The IC 2602 cluster is visible
naturally near $(\ell,b)=(290^\circ,-5^\circ)$. An additional population
located at ($b\sim5^\circ$ and $\ell\sim345^\circ$) with a mean distance of
$\sim180\mathrm{pc}$ ($5$-$6$~mas) is observed. This is consistent with
previous studies reported in the literature.
