Abstract
We present ALMA observations of the CO(2-1) and CO(3-2) molecular gas
transitions and associated (sub)-mm continua of the nearby Seyfert 1.5 galaxy
NGC3227 with angular resolutions 0.085-0.21" (7-15pc). On large scales the cold
molecular gas shows circular motions as well as streaming motions on scales of
a few hundred parsecs associated with a large scale bar. We fitted the nuclear
ALMA 1.3mm emission with an unresolved component and an extended component. The
850$\mu$m emission shows at least two extended components, one along the major
axis of the nuclear disk and the other along the axis of the ionization cone.
The molecular gas in the central region (1" ~73pc) shows several CO clumps with
complex kinematics which appears to be dominated by non-circular motions. While
we cannot demonstrate conclusively the presence of a warped nuclear disk, we
also detected non-circular motions along the kinematic minor axis. They reach
line-of-sight velocities of v-vsys =150-200km/s. Assuming that the radial
motions are in the plane of the galaxy, then we interpret them as a nuclear
molecular outflow due to molecular gas in the host galaxy being entrained by
the AGN wind. We derive molecular outflow rates of $5\,M_ødot\,yr^-1$
and $0.6\,M_ødot\,yr^-1$ at projected distances of up to 30pc to the
northeast and southwest of the AGN, respectively. At the AGN location we
estimate a mass in molecular gas of $510^5\,M_ødot$ and an average
column density $N(H_2) = 2-310^23\,cm^-2$ in the inner
15pc. The nuclear molecular gas and sub-mm continuum emission of NGC3227 do not
resemble the classical compact torus. Rather, these emissions extend for
several tens of parsecs and appear connected with the circumnuclear ring in the
host galaxy disk, as found in other local AGN. (Abridged)
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