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A New Look at Poor Groups of Galaxies

Published online by Cambridge University Press:  25 May 2016

Ann I. Zabludoff*
Affiliation:
UCO/Lick Observatory and Astronomy Department, University of California, Santa Cruz, CA 95064

Abstract

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We use a new fiber spectroscopic survey of 12 nearby, poor groups of galaxies to examine the dynamics and evolution of galaxies in these common, but poorly studied, environments. Some of our conclusions are: (1) The nine groups in our sample with diffuse X-ray emission are in fact bound systems with at least 20-50 group members with absolute magnitudes as faint as MB ~ −14 + 5 log10h. (2) Galaxies in each X-ray-detected group have not all merged together because a significant fraction of the group mass lies outside of the galaxies and in a common halo, thereby reducing the rate of galaxy-galaxy interactions. (3) The similarity of the recent star formation histories and the fraction of early type galaxies in some poor groups to those in rich clusters suggest that cluster-specific environmental effects may not play a dominant role in the recent evolution of cluster galaxies. The evolution of group and cluster members may be driven instead by galaxy-galaxy interactions, which are likely to occur with equal frequency in field groups and in groups that have recently fallen into clusters (i.e., subclusters).

Type
Part 4. Morphology, Kinematics and Dynamics
Copyright
Copyright © Astronomical Society of the Pacific 1999 

References

Athanssoula, E., Makino, J., Bosma, A. 1997, MNRAS, 286, 825 CrossRefGoogle Scholar
Barnes, J. 1985, MNRAS, 215, 517 CrossRefGoogle Scholar
Bode, P.W., Cohn, H.N., Lugger, P.M. 1993, ApJ, 416, 17 CrossRefGoogle Scholar
Caldwell, N., Rose, J. 1997, AJ, 113, 492 CrossRefGoogle Scholar
Diaferio, A., Geller, M., Ramella, M. 1995, AJ, 109, 2293 CrossRefGoogle Scholar
Governato, F., Bhatia, R., Chincarini, G. 1991, ApJ, 371, L15 CrossRefGoogle Scholar
Hickson, P., Huchra, J., Kindl, E. 1988, ApJ, 331, 64 CrossRefGoogle Scholar
Hickson, P. 1982, ApJ, 255, 382 CrossRefGoogle Scholar
Huchra, J.P., Geller, M.J., Corwin, H. 1995, ApJS, 99, 391 CrossRefGoogle Scholar
Kennicutt, R.C., Roettiger, K.A., Keel, W.C., Van der Hulst, J.M., Hummel, E. 1987, ApJ, 93, 1011,CrossRefGoogle Scholar
Lonsdale, C.J., Persson, S.E., Matthews, K. 1984, ApJ, 287, 95 CrossRefGoogle Scholar
Longo, G., Busarello, G., Lorrenz, H., Richter, G., Zaggia, S. 1994, A&A, 282, 418 Google Scholar
Mulchaey, J.S., Zabludoff, A.I. 1998, ApJ, 496, 73 CrossRefGoogle Scholar
Mulchaey, J., Davis, D., Mushotzky, R., Burstein, D. 1996, ApJ, 456, 80 CrossRefGoogle Scholar
Oemler, A. 1992, in: Clusters and Superclusters of Galaxies , (ed.) Fabian, A.C. (Dordrecht: Kluwer), p. 29 CrossRefGoogle Scholar
Ponman, T., Bourner, P., Ebeling, H., Bohringer, H. 1996, MNRAS, 283, 690 CrossRefGoogle Scholar
Ramella, M., Geller, M.J., Huchra, J.P. 1989, ApJ, 344, 57 CrossRefGoogle Scholar
Sanders, D.B., Soifer, B.T., Elias, J.H., Matthews, K., Madore, B.F. 1988, ApJ, 325, 74 CrossRefGoogle Scholar
van den Bergh, S. 1992, A&A, 264, 75 Google Scholar
Whitmore, B., Gilmore, D., Jones, C. 1993, ApJ, 407, 489 CrossRefGoogle Scholar
Zabludoff, A.I., Mulchaey, J.S. 1998a, ApJ, 496, 39 CrossRefGoogle Scholar
Zabludoff, A.I., Mulchaey, J.S. 1998b, ApJ, 498, L5 CrossRefGoogle Scholar
Zaritsky, D. 1994, in: The Local Group: Comparative and Global Properties , (eds.) Layden, A., Smith, R. C., & Storm, J., ESO Conference and Workshop Proceedings No. 51, p. 187 Google Scholar