THE IONIZED-GAS AND RADIO HALO OF NGC-3432 (ARP-206)

VLA data of the interacting galaxy, NGC 3432, display a radio continuu m halo, with a maximum extent of 5.3 kpc in projection above the plane , containing considerable substructure and discrete radio continuum '' spurs.'' The detection of high latitude H alpha emission, either in th e form of an extended diffuse layer (DIG) or in discrete features, is often assumed to independently confirm the correlation of disk-halo in teractions and underlying star formation. However, the possibly extra- planar optical features in our narrowband H alpha CCD images, acquired at Observatoire Mont Megantic, contain a significant stellar componen t suggesting they are not gaseous debris resulting from a ''blow out'' by star formation activity in the disk but rather are tidal features. Although the inclination (79 degrees) of NGC 3432 hinders our ability to detect a DIG halo surrounding this galaxy with these data, we can confirm that it has a lower star formation rate than the Milky Way. He nce it is an interesting counter-example to the notion that pervasive radio halos exist in galaxies with high star formation rates. We sugge st that the interaction between NGC 3432 and UGC 5983, rather than dis k-halo outflow in NGC 3432, is responsible for any extra-planar featur es as well as the extended radio continuum halo. (C) 1997 American Ast ronomical Society.