Rapid turn-on of a luminous X-ray source in the candidate Lyman
  continuum emitting galaxy Tol 0440-381
  Chandra observations of the nearby, candidate Lyman-continuum (LyC) emitting
galaxy Tol 0440-381 show brightening of an X-ray source by at least a factor of
4 to a luminosity of 1.6E40 erg/s over 3.8~days. The X-ray emission likely
arises from either a low-luminosity AGN or an ultraluminous X-ray source. The
properties of the X-ray source are similar to those found in Haro 11 and Tololo
1247-232, the only other LyC-emitting galaxies that have been resolved in
X-rays. All three galaxies host luminous, variable, and hard spectrum X-ray
sources that are likely accretion-powered. Accretion onto compact objects
produces powerful outflows and ionizing radiation that could help enable LyC
escape.
