Abstract
The large nitrogen abundance that is inferred in both narrow and (at high red-shift) broad-line regions of AGNs, if real, could be due to global effects of galactic chemical evolution or to local pollution of the ionized region by winds from massive stars. In the latter case, one might expect to find an associated excess of helium, similar to (but larger than) what has been found in some H II galaxies showing broad spectral features due to embedded Wolf-Rayet stars. However, no clear sign of any excess of helium is found in Koski's data on Seyfert 2's.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Bergeron, J.: 1983, in: P.A. Shaver, D. Kunth and K. Kjär (eds.)Primordial Helium, ESO, Garching, p. 329.
Campbell, A.W., Terlevich, R.J. and Melnick, J.: 1986,Monthly Not. Roy. Astr. Soc. 211, 15.
Cid Fernandes, R., Jr.et al.: 1992,Monthly Not. Roy. Astr. Soc. 255, 165.
Clegg, R.E.S.: 1987,Monthly Not. Roy. Astr. Soc. 229, 31P.
Esteban, C.et al.: 1992,Astron. Astrophys. 259, 629.
Hamann, F. and Ferland, G.: 1992,Astrophys. J. Lett. 391, L53.
Koski, A.T.: 1978,Astrophys. J. 223, 56.
Kwitter, K.B.: 1984,Astrophys. J. 287, 840.
Pagel, B.E.J.: 1987, in: T.X. Thuan, T. Montmerle and J.T.T. Van (eds.)Starbursts and Galaxy Evolution, Ed. Frontières, Paris, p. 227.
Pagel, B.E.J.et al.: 1992,Monthly Not. Roy. Astr. Soc. 255, 325.
Pagel, B.E.J., Terlevich, R.J. and Melnick, J.: 1986,Publ. Astron. Soc. Pacific 98, 1005.
Smith, L.J.et al.: 1988,Monthly Not. Roy. Astr. Soc. 234, 625.
Walsh, J.R. and Roy, J.-R. 1989:Monthly Not. Roy. Astr. Soc. 239, 297.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Pagel, B.E.J. Nitrogen and helium pollution in H II galaxies and AGNs. Astrophys Space Sci 205, 123–126 (1993). https://doi.org/10.1007/BF00657966
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF00657966