Hostname: page-component-8448b6f56d-42gr6 Total loading time: 0 Render date: 2024-04-23T09:41:21.727Z Has data issue: false hasContentIssue false

The Dynamical Masses of Tidal Dwarf Galaxies

Published online by Cambridge University Press:  26 May 2016

J. E. Hibbard
Affiliation:
NRAO, USA
J. E. Barnes
Affiliation:
Institute for Astronomy, USA

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

A variety of substructures have been identified within the tidal debris around interacting galaxies. These structures range in scale from Globular Clusters to the so-called “Tidal Dwarf Galaxies”. We review observations of such objects, with particular emphasis on what can be inferred from dynamical mass estimates. We then present the results of a dynamical analysis of structures which develop within the tidal tails of a large-N numerical simulation (N~1 million). We find that under the best conditions, “observations” of this system recover the true mass of the bound substructures to within a factor of two. Poor spatial and velocity resolution (coarser than the true half-light radii and velocity dispersions) and more inclined viewing geometries lead the dynamical masses to be over-estimated by factors of ten or more. A combination of poor resolution and edge-on viewing geometries lead to the most dramatic discrepancies, with dynamical masses over-estimated by factors of up to 1000. Furthermore, projection effects can lead to apparent concentrations of material at the ends of tidal tails that is in reality spread over very large distances, with mass scales well beyond that of any truly bound regions. Since many of the well studied tidal dwarf candidates are found within edge-on tails, we conclude that their mass and extent may have been greatly over-estimated.

Type
Part 4. Recycling
Copyright
Copyright © Astronomical Society of the Pacific 2004 

References

Barnes, J. E. 2003, MNRAS, submitted2 .Google Scholar
Barnes, J. E., & Hernquist, L. 1992, Nature, 360, 715.Google Scholar
Braine, J., Duc, P.-A., Lisenfeld, U., Leon, S., Vallejo, O., Charmandaris, V. & Brinks, E. 2001, A&A, 378, 51.Google Scholar
Braine, J., Lisenfeld, U., Duc, P.-A., & Leon, S., 2000, Nature, 403, 867.Google Scholar
de Grijs, R., Lee, J.T., Clemencia Mora Herrera, M., Fritze-v. Alvensleben, U., Anders, P. 2003, New Ast., 8, 155.Google Scholar
Duc, P. -A., Mirabel, I. F. 1994, A&A, 289, 83.Google Scholar
Duc, P. -A., Brinks, E., Wink, J. E., & Mirabel, I. F. 1997, A&A, 326, 537.Google Scholar
Duc, P. -A., Brinks, E., Springel, V., Pichardo, B., Weilbacher, P., & Mirabel, I.F., 2000, AJ, 120, 1238.Google Scholar
Elmegreen, B., Kaufmann, M., & Thomasson, M. 1993, ApJ, 412, 90.Google Scholar
English, J., Norris, R. P., Freeman, K. C., & Booth, R. S. 2003, AJ, 125, 1134.Google Scholar
Hibbard, J. E., & van Gorkom, J. H. 1996, AJ, 111, 655.Google Scholar
Hibbard, J. E., Guhathakurta, P., van Gorkom, J. H., & Schweizer, F. 1994, AJ, 107, 67.Google Scholar
Hibbard, J. E., van der Hulst, J. M., Barnes, J. E., & Rich, R.M. 2001, AJ, 122, 2969.Google Scholar
Hunsberger, S., Charlton, J., & Zaritsky, D. 1998, ApJ, 505, 536.Google Scholar
Hunter, D. A., Hunsberger, S., & Roye, E.W. 2000, ApJ, 542, 137.Google Scholar
Hutchings, J. B. 1996, AJ, 111, 712.Google Scholar
Iglesias-Páramo, J., & Vílchez, J. M. 2001, ApJ, 550, 204.Google Scholar
Knierman, K. A., Gallagher, S. C., Charlton, J. C., Hunsberger, S. D., Whitmore, B., Kundu, A., Hibbard, J. E., & Zaritsky, D. 2004, AJ, in press.Google Scholar
Malphrus, B. K., Simpson, C. E., Gottesman, S. T., & Hawarden, T. G. 1997, AJ, 114, 1427.Google Scholar
Mendes de Oliveira, C., Plana, H., Amram, P., Balkowski, C., & Bolte, M., 2001, AJ, 121, 2524.CrossRefGoogle Scholar
Mirabel, I. F., Dottori, H., & Lutz, D. 1992, A&A, 256, L19.Google Scholar
Pfenniger, D., Combes, F., & Martinet, L. 1994, A&A, 285, 79.Google Scholar
Saviane, I., Hibbard, J.E. & Rich, 2004, AJ, in press.Google Scholar
Schweizer, F. 1978, The Structure and Properties of Nearby Galaxies, IAU Symp. No. 77, edited by Berkhuijsen, E. M. and Wielebinski, R. (Reidel, Dordrecht), 279.Google Scholar
Smith, B. J., & Higdon, J. L. 1994, AJ, 108, 837.Google Scholar
Sparke, L.S. & Gallagher, J.S. III 2000, Galaxies in the Universe: an Introduction, (Cambridge: Cambridge Univ. Press)Google Scholar
Temporin, S., Weinberger, R., Galaz, G., & Kerber, F. 2003, ApJ, 587, 660.Google Scholar
Tran, H. D. et al. 2003, 585, 750.Google Scholar
Weilbacher, P. M., Duc, P.-A., Fritze-v. Alvensleben, U., Martin, P., & Fricke, K. J. 2000, A&A, 358, 819.Google Scholar
Weilbacher, P. M., Duc, P.-A., & Fritze-v. Alvensleben, U. 2003, A&A, 397, 545.Google Scholar
Weilbacher, P. M., Fritze-v. Alvensleben, U., Duc, P.-A., & Fricke, K. J. 2002, ApJ, 579, L79.Google Scholar
Zwicky, F. 1956, Ergebnisse der Exakten Naturwissenschaften, 29, 344.Google Scholar