We have performed two surveys namely HI survey and Ha survey of a sample of WR galaxies. The main
aims of this study are to see the optical and radio morphology of these galaxies and role of environment
interactions in triggering the starburst in them and to find the star formation rate in the sample galaxies
using Ha data and compare it with other SFR indicators.
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We present the gray-scale Ha and R band images of few galaxies of our sample in figure 1. All the
images have their north up and east left. A linear scale-length in kpc is shown at the bottom of each image.
The R-band images traces the old stellar population in the galaxy and therefore it can provide the features of
galaxy interactions. On the other hand, the Ha images traces the ionized gas (HII regions) and therefore it
provides the distribution of star forming regions in the host galaxy with respect to the environmental effects.
The clear interaction features can be seen in most of the galaxies in the sample. This result can be used
to speculate that the galaxy-galaxy tidal interaction could be the main cause of massive star formation in
galaxies.
We also present the HI column density maps of few galaxies of our sample in figure 2. The HI column
density contours are overlaid on the gray-scale DSS image. These images show a clear indication of tidal
interaction in these galaxies through various asymmetries.