Hostname: page-component-76fb5796d-x4r87 Total loading time: 0 Render date: 2024-04-27T03:27:52.728Z Has data issue: false hasContentIssue false

The Detailed Velocity Field of the Ionized Gas in NGC 4038/39 (The “Antennae”)

Published online by Cambridge University Press:  03 August 2017

P.H. Amram
Affiliation:
Observatoire de Marseille 2 Place Le Verrier 13248 Marseille cedex 04, France
J. Boulesteix
Affiliation:
Observatoire de Marseille 2 Place Le Verrier 13248 Marseille cedex 04, France
M. Marcelin
Affiliation:
Observatoire de Marseille 2 Place Le Verrier 13248 Marseille cedex 04, France

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.

The pair of galaxies NGC 4038/39 (Arp, 244) has been observed at Hα wavelength with a scanning Pérot-Fabry interferometer and an IPCS at the Cassegrain focus of the 3.6 m ESO telescope. Hα profiles were thus obtained inside 256 × 256 pixels (0.91″ × 0.91″ each), providing 5741 velocity points with an accuracy better than 16 km s-1, covering the central part of the merging system. The velocity field exhibits severe distortions, not surprising because of the strong interaction. Comparison of our data with recent CO data (Stanford et al., 1990) inside NGC 4039 show a fairly good agreement. The grand design of the velocity field of NGC 4038 more clearly reminds of a classical rotating disk. A rough estimate of the masses of the galaxies indicates that they are both around 1010 M within a radius of 40″. Comparison with the most recent model of the antennae (Barnes, 1988) shows a strong discrepancy, the observed radial velocity range being half the expected value and the nuclei velocities differing by only 30 km s-1 instead of the expected 300 km s-1.

Type
VI- Other Gaseous Components
Copyright
Copyright © Kluwer 1991 

References

Arp, H.: 1966, Atlas of Peculiar Galaxies (Carnegie Institution of Washington)Google Scholar
Barnes, J.: 1988, Astrophys. J. 331, 699 CrossRefGoogle Scholar
Boulesteix, J. et al.: 1983, SPIE, Conf. Inst. Astron V 445, 37 Google Scholar
Hummel, E., Van der Hulst, J.M.: 1986, Astron. Astrophys. 155, 151 Google Scholar
Laval, A. et al.: 1987, Astron. Astrophys. 175, 199 Google Scholar
Lequeux, J.: 1983, Astron. Astrophys. 125, 394 Google Scholar
Rubin, V.C., Ford, W.K., D'Odorico, S.: 1970, Astrophys. J., 160, 801 Google Scholar
Schweizer, F.: 1978, in IAU Symp. 77, p 279 Google Scholar
Stanford, S.A. et al.: 1990, Astrophys. J., 349, 492 Google Scholar
Toomre, A., Toomre, J.: 1972, Astrophys. J. 178, 623 CrossRefGoogle Scholar