In Search of $\ldots$ Dwarfs in the Tidal Debris of Compact Groups
Session 61 -- Properties and Evolution of Clusters of Galaxies
Display presentation, Thursday, 2, 1994, 9:20-6:30

## [61.04] In Search of $\ldots$ Dwarfs in the Tidal Debris of Compact Groups

S. D. Hunsberger (Penn State), D. Zaritsky (Carnegie Observatories), $\;$ J. C. Charlton (Penn State)

Tidal forces extract material from interacting galaxies and form bridges and tails of gas and stars. Recent observational results support the idea, presented by Zwicky (1956) and confirmed by N-body simulations (Barnes and Hernquist 1992), that self-gravitating objects within such tidal debris could evolve into small galaxies. For example, Mirabel et al. (1991) observed a region of active star formation at the tip of the southern tail of the Superantennae, and Mirabel et al. (1992) observed a nascent dwarf irregular galaxy at the tip of the Antennae. \par We present moderately deep CCD images of 52 Hickson compact groups and results from a search for condensed objects in tidal tails within these groups. Tidal tails are expected in compact groups because the number density of galaxies is similar to that of rich clusters, where interactions are common. However, because the groups were not chosen due to the presence of tidal tails, this work presents an unbiased study of dwarf galaxy formation in tidal tails within an environment where such tails should be common. The results to date are presented here. \bigskip \par \noindent Barnes, J.E. \& Hernquist, L.E. 1992, Nature , {\bf360}, 715 \newline Mirabel, I.F., Dottori, H. \& Lutz, D. 1992, A\&A, {\bf256}, L19 \newline Mirabel, I.F., Lutz, D. \& Maza, J. 1991, A\&A, {\bf243}, 367 \newline Zwicky, F. 1956, Ergebnisse der Exakten Naturwissenschaften , {\bf29}, 344