Spatially resolved molecular interstellar medium in a $z=6.6$ quasar
  host galaxy
  We present high spatial resolution (0.4", 2.2kpc) observations of the
CO(6-5), CO(7-6) and [CI] lines and dust continuum emission from the
interstellar medium in the host galaxy of the quasar J0305$-$3150 at $z=6.6$.
These, together with archival [CII] data at comparable spatial resolution,
enable studies of the spatial distribution and kinematics between the ISM in
different phases. When comparing the radial profiles of CO, [CII] and the dust
continuum, we find that the CO and dust continuum exhibit similar spatial
distributions, both of which are less extended than the [CII], indicating that
the CO and dust continuum are tracing the same gas component, while the [CII]
is tracing a more extended one. In addition, we derive the radial profiles of
the [CII]/CO, [CII]/far-infrared (FIR), CO/FIR, and dust continuum $S_{98.7 \rm
GHz}/S_{258.1 \rm GHz}$ ratios. We find a decreasing $S_{98.7 \rm GHz}/S_{258.1
\rm GHz}$ ratio with radius, possibly indicating a decrease of dust optical
depth with increasing radius. We also detect some of the ISM lines and
continuum emission in the companion galaxies previously discovered in the field
around J0305$-$3150. Through comparing the line-to-line and line-to-FIR ratios,
we find no significant differences between the quasar and its companion
galaxies.
