A NEUTRAL HYDROGEN STUDY OF THE SEYFERT-GALAXY NGC-5033

Neutral hydrogen observations of 22.7 x 18.5 arcsec(2) resolution are presented for the Seyfert type 1 galaxy NGC 5033. Our measurements sho w that the total HI mass of the galaxy is 7.0 x 10(9) M. and that it i s receding at 870 km s(-1). The column density map features prominent HI spiral arms and an asymmetric plume of HI which extends similar to 6 kpc south of the galaxy. We find a well-ordered velocity held and th e large-scale kinematical warp in the galactic disc has been modelled. The inner region of the velocity field is well fitted by a flat, incl ined disc with inclination 68 degrees and position angle 352 degrees, but due to warping these fall to 64 degrees and 342 degrees, respectiv ely, at large radii. Attention is paid to factors that may be related to Seyfert activity in the nucleus and we fmd some evidence for a prev ious tidal encounter but little evidence for a bar, or significant non -circular motions in the central regions. Large concentrations of HI a t the galactic centre appear to show no evidence of interaction with t he active nucleus.