Hostname: page-component-8448b6f56d-tj2md Total loading time: 0 Render date: 2024-04-19T13:02:26.810Z Has data issue: false hasContentIssue false
  • English
  • Français

Free–Floating HI Clouds in the M 81 Group

Published online by Cambridge University Press:  01 June 2007

Elias Brinks ,
Fabian Walter  and
Evan D. Skillman
Elias Brinks
Affiliation:
Centre for Astrophysics Research, University of Hertfordshire, College Lane, Hatfield AL10 9AB, United Kingdom email: E.Brinks@herts.ac.uk
Fabian Walter
Affiliation:
Max–Planck–Institut für Astronomie, Königstuhl 17, 69117 Heidelberg, Germany email: walter@mpia.de
Evan D. Skillman
Affiliation:
Dept. of Astronomy, Univ. of Minnesota, 116 Church St. SE, Minneapolis, MN 55455, USA email: skillman@astro.umn.edu
Rights & Permissions [Opens in a new window]

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.

Recent VLA observations pointed at dwarf spheroidal (dSph) galaxies in the M 81 group reveal a hitherto hidden population of extremely low mass (~ 105 M⊙) HI clouds with no obvious optical counterparts. We have searched 10 fields in the M 81 group totalling 2.2 square degree, both targeting known dwarf spheroidal galaxies and blank fields around the central triplet. Our observations show that the new population of low–mass HI clouds appears to be confined to a region toward the south–east of the central triplet (at distances of ~ 100 kpc from M 81). Possible explanations for these free–floating HI clouds are that they are related to the dSphs found to the South–East of M 81, that they belong to the galaxies of the M 81 triplet (equivalent to HVCs), that they are of primordial nature and provide fresh, unenriched material falling into the M 81 group, or that they are tidal debris from the 3–body interaction involving M 81–M 82–NGC 3077. Based on circumstantial evidence, we currently favour the latter explanation.

Keywords

galaxies: individual (M81)galaxies: interactionsintergalactic mediumradio lines: galaxies
Type
Contributed Papers
Information
Proceedings of the International Astronomical Union , Volume 3 , Symposium S244: Dark Galaxies and Lost Baryons , June 2007 , pp. 120 - 126
Copyright
Copyright © International Astronomical Union 2008

References

Appleton, P. N., Davies, R. D. & Stephenson, R. J. 1981, MNRAS 195, 327CrossRefGoogle Scholar
Boyce, P. J., Minchin, R. F., Kilborn, V. A., Disney, M. J., Lang, R. H., Jordan, C. A., Grossi, M., Lyne, A. G., Cohen, R. J., Morison, I. M. & Phillipps, S. 2001, ApJ (Letters) 560, L127Google Scholar
de Blok, W. J. G., Zwaan, M. A., Dijkstra, M., Briggs, F. H. & Freeman, K. C. 2002, A&A 382, 43Google Scholar
Freedman, W. L., et al. , 2001, ApJ 553, 47Google Scholar
Froebrich, D. & Meusinger, H. 2000, A&AS 145, 229Google Scholar
Huchtmeier, W. K. & Skillman, E. D. 1998, A&AS 127, 269Google Scholar
Huchtmeier, W. K., Karachentsev, I. D., Karachentseva, V. E. & Ehle, M. 2000, A&AS 141, 469Google Scholar
Karachentsev, I. D. & Kaisin, S. S. 2007, AJ 133, 1883CrossRefGoogle Scholar
Lo, K. Y. & Sargent, W. L. W. 1979, ApJ 227, 756CrossRefGoogle Scholar
Mateo, M. L. 1998, ARAA 36, 435Google Scholar
Pisano, D. J., Barnes, D. G., Gibson, B. K., Staveley–Smith, L., Freeman, K. C. & Kilborn, V. A. 2004 ApJ (Letter) 610, L17CrossRefGoogle Scholar
Pisano, D. J., Barnes, D. G., Gibson, B. K., Staveley–Smith, L., Freeman, K. C. & Kilborn, V. A. 2007 ApJ 662, 959CrossRefGoogle Scholar
Simien, F. & Prugniel, Ph. 2002, A&A 384, 371Google Scholar
Skillman, E. D., Côté, S. & Miller, B. W. 2003, AJ 125, 593CrossRefGoogle Scholar
Yun, M. S., Ho, P. T. P. & Lo, K. Y. 1994, Nature 372, 530CrossRefGoogle Scholar
Yun, M. S. 1997, in: Barnes, J. E., and Sanders, D. B. (eds.), Galaxy Interactions at Low and High Redshift Proceedings of IAU Symposium 186 p. 81Google Scholar
Yun, M. S., Ho, P. T. P. & Lo, K. Y. 2000, in: Mangum, J.G. & Radford, S.J.E. (eds.), Imaging at Radio through Submillimeter Wavelengths, ASP Conf. Proc. Vol. 217, p. 374Google Scholar
Walter, F., Skillman, E. D. & Brinks, E. 2005, ApJ (Letters) 627, L105CrossRefGoogle Scholar
Zwaan, M. A. & Briggs, F. H. 2000, ApJ (Letters) 530, L61CrossRefGoogle Scholar