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| - Atomic and molecular gas in the starburst galaxy NGC 4945
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| - Spatial and kinematical correlations between the H i and 12CO(2-1) emission of the southern spiral galaxy NGC 4945 are studied with a common angular resolution of ~23 '' (corresponding to 750 pc at $D=6.7$ Mpc) and a velocity resolution of ~7 ${\rm km s}^{-1}$. The 1.4 GHz continuum emission is also observed. The H i kinematics yield a galaxy mass of ~ $1.4\times10^{11}$$M_{odot}$ within radius $R=380''$, with molecular and neutral atomic gas each contributing ~2% , respectively. A central continuum source of size 7 $ .\!\!^{\prime\prime}$6 $\times$ 3 $ .\!\!^{\prime\prime}$4 (250 $\times$ 110 pc) is enveloped by a molecular cloud of mass $1.5\times10^9$$M_{odot}$ for R≤ 7 $ .\!\!^{\prime\prime}$5, and is rapidly rotating with $V_{\rm rot} \sim 160$${\rm km s}^{-1}$. H i emission from the central region at velocities $|V-$Vsys$|$> 200 ${\rm km s}^{-1}$ may be related to optically detected gas that is believed to trace an outflow directed towards the halo. Nuclear H i absorption at V - Vsys ~ +80 ${\rm km s}^{-1}$ suggests inflow towards the centre, that was so far only seen in molecular lines. H i features at each end of the major axis ( $|R|$ ~ 600 '') are interpreted as spiral arms that are viewed tangentially and that also cause prominent emission features in the radio continuum, H i, and CO further inside the galaxy. A central elongated region showing non-circular motions is interpreted as a bar which fuels the nuclear starburst. The H i and CO position-velocity data have been analysed using linear resonance theory, and possible locations of resonances are identified.
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