Double-peaked OI profile: a likely signature of the gaseous ring around
  KH 15D
  KH 15D is a well-known spectroscopic binary because of its unique and
dramatic photometric variability. The variability is explained by a
circumbinary dust ring but the ring itself was never directly detected. We
present a new interpretation of the double-peaked [O~{\scriptsize
I}]\,$\lambda$6300 profiles as originating from the hot disk surface of KH 15D.
By modeling these profiles, we measure emitting radii between $\sim$0.5--5 au,
basically a gaseous ring very similar in radial extent to the dust ring
inferred from modeling the system's photometric variability. We also discuss
the possibility that external photoevaporation driven by UV photons from the
nearby massive star HD~47887 has truncated the outer edge of the disk to the
observed value.
