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The Diffuse Ionized Gas Perpendicular to the Plane of NGC 891

Published online by Cambridge University Press:  03 August 2017

R.-J. Dettmar
Affiliation:
(1) Radioastr. Inst. Uni. Bonn, Auf dem Hügel 71, D-5300 Bonn, FRG
J.W. Keppel
Affiliation:
(2) 603 Pauley Dr., Prescott, AZ 86301, USA
M.S. Roberts
Affiliation:
(3) NRAO, Edgemont Rd., Charlottesville, VA 22901, USA
J.S. Gallagher
Affiliation:
(4) AURA Inc., 1625 Massachusetts Ave., Washington, DC 20036, USA

Abstract

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Hα images and long-slit spectra of NGC 891 show the presence of a thick layer of diffuse ionized gas (DIG) in this edge-on galaxy. Hα emission originating in the DIG of NGC 891 is detected out to several kpc above the midplane with a typical scale height for the electron density ne(z) of he ~ 600 pc. The distribution of the gas is very inhomogeneous with a large scale asymmetry and filamentary structure. Individual Hα emitting structures can be traced out to 4-5 kpc above the midplane. The emission line ratios of [NII] and [SII] to Hα vary with height above the disk. We compare these properties with the analogous gas phase in our Galaxy.

The distribution of the DIG is related to star formation in the underlying galactic disk and we conclude that in NGC 891 the interstellar medium is heavily effected by processes related to star formation.

Type
II. The Disk-Halo Interface in Other Galaxies
Copyright
Copyright © Kluwer 1991 

References

REFERENCES

Dettmar, R.-J. (1990) Astron. Astrophys. Lett. 232, L15 Google Scholar
Dettmar, R.-J., Dahlem, M. (1990) this conference, Poster Proceedings , ed. Bloemen, H., Sterrewacht Leiden, p. 41 Google Scholar
Koo, B.-C., Heiles, C., Reach, W. T. (1990) this conference Google Scholar
Mathis, J. S. (1986) Astrophys. J. 301, 423 Google Scholar
Norman, C. A., Ikeuchi, S. (1990) Astrophys. J 345, 372 Google Scholar
Rand, R. J., Kulkarni, S. R., Hester, J. J. (1990) Astrophys. J. Lett. 352, L1 Google Scholar
Reynolds, R. (1990) in IAU Symposium No. 139, Galactic and Extragalactic Background Radiation , eds. Bowyer, S. and Leinert, C. Google Scholar
Sancisi, R., Allen, R. J. (1979) Astron. Astrophys. 74, 73 Google Scholar