The emission-line spectrum of KUG 1031+398 and the Intermediate Line Region

A. C. Goncalves; P. Veron; M. -P. Veron-Cetty

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arXiv · astro-ph/9811003

The emission-line spectrum of KUG 1031+398 and the Intermediate Line Region

A. C. Goncalves·P. Veron·M. -P. Veron-Cetty

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Abstract

We present results based on the analysis of optical spectra of KUG 1031+398, a Narrow Line Seyfert 1 (NLS1) galaxy for which Mason et al. (1996) reported evidence for a line-emitting region "intermediate" (both in terms of velocity and density) between the conventional broad and narrow line regions (BLR and NLR, respectively). From our observations and modelling of the spectra, we get a consistent decomposition of the line profiles into four components: an extended H II region with unresolved lines, two distinct Seyfert-type clouds identified with the NLR, and a relatively narrow "broad line" component emitting only Balmer lines but no forbidden lines. Therefore, and although we find this object to be exceptional in having line-emission from the BLR with almost the same width as the narrow lines, our interpretation of the data does not support the existence of an "intermediate" line region (ILR).

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A. C. Goncalves, P. Veron, M. -P. Veron-Cetty. 1998-10-31. The emission-line spectrum of KUG 1031+398 and the Intermediate Line Region. https://arxiv.org/abs/astro-ph/9811003

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