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arXiv · astro-ph/0310623

Emission and absorption in Narrow-Line Seyfert 1 Galaxies

Anca Constantin·Joseph C. Shields
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Abstract

The emission and absorption attributes of the UV-blue nuclear spectra of the Narrow-Line Seyfert 1 (NLS1) galaxies are analyzed based on high quality archival HST observations. Measurements from composite spectra as well as from individual sources reveal differences from the more general AGN samples: NLS1s have steeper (redder) UV-blue continua. Objects with UV line absorption show redder spectra, suggesting that internal dust is important in modifying the continuum shapes. A strong relationship is found between the slopes of the power-laws that best fit the UV-blue continua and the luminosities: the more luminous sources have bluer SEDs. This trend is possibly attributed to a luminosity-dependent inner geometry of the obscuring (dusty) material.

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Anca Constantin, Joseph C. Shields. 2003-10-21. Emission and absorption in Narrow-Line Seyfert 1 Galaxies. https://arxiv.org/abs/astro-ph/0310623

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