Anisotropic ionizing radiation in NGC5252

Clive Tadhunter, Zlatan Tsvetanov

Research output: Contribution to journalArticle

142 Citations (Scopus)

Abstract

THE different kinds of active galactic nuclei (AGNs) and quasars may be fundamentally similar, and owe their observed differences to anisotropy in the distribution of their emitted radiation: apparently different objects may then be the same thing seen from different viewpoints. In particular, it has been proposed that narrow-line Seyfert 2 galaxies are Seyfert 1 galaxies for which the broad-line and continuum emitting regions are hidden by obscuring material along our line of sight1,2 Here we present narrow-band imaging observations of the Seyfert 2 galaxy NGC5252 which strongly support such unifying hypotheses. Images in the light of the [O III] line at λ = 5,007 Å reveal a sharply defined bi-conical structure extending to a maximum radius of ∼33 kpc (H0 = 50 km s-1 Mpc-11) along the radio-emission axis. This is just the type of structure expected if the ionizing-radiation field from the nucleus is anisotropic. A map of the ratio of the [O III] and Hα lines shows a central band perpendicular to the cones that we identify as the disk or torus responsible for collimating the radiation field.

Original languageEnglish
Pages (from-to)422-424
Number of pages3
JournalNature
Volume341
Issue number6241
Publication statusPublished - 1989
Externally publishedYes

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Galaxies
Ionizing Radiation
Narrow Band Imaging
Radiation
Anisotropy
Radio

ASJC Scopus subject areas

  • General

Cite this

Tadhunter, C., & Tsvetanov, Z. (1989). Anisotropic ionizing radiation in NGC5252. Nature, 341(6241), 422-424.

Anisotropic ionizing radiation in NGC5252. / Tadhunter, Clive; Tsvetanov, Zlatan.

In: Nature, Vol. 341, No. 6241, 1989, p. 422-424.

Research output: Contribution to journalArticle

Tadhunter, C & Tsvetanov, Z 1989, 'Anisotropic ionizing radiation in NGC5252', Nature, vol. 341, no. 6241, pp. 422-424.
Tadhunter C, Tsvetanov Z. Anisotropic ionizing radiation in NGC5252. Nature. 1989;341(6241):422-424.
Tadhunter, Clive ; Tsvetanov, Zlatan. / Anisotropic ionizing radiation in NGC5252. In: Nature. 1989 ; Vol. 341, No. 6241. pp. 422-424.
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