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arXiv · 1311.6653

A model for the Balmer pseudocontinuum in spectra of type 1 AGNs

Jelena Kovacevic·Luka C. Popovic·Wolfram Kollatschny
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Abstract

Here we present a new method for subtracting the Balmer pseudocontinuum in the UV part of type 1 AGN spectra. We calculate the intensity of the Balmer pseudocontinuum using the prominent Balmer lines in AGN spectra. We apply the model on a sample of 293 type 1 AGNs from SDSS database, and found that our model of Balmer pseudocontinuum + power law continuum very well fits the majority of the AGN spectra from the sample, while in 15% of AGNs, the model fits reasonable the UV continuum, but a discrepancy between the observed and fitted spectra is noted. Some of the possible reasons for the discrepancy may be a different value for the optical depth in these spectra than used in our model or the influence of the intrinsic reddening.

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Jelena Kovacevic, Luka C. Popovic, Wolfram Kollatschny. 2013-11-26. A model for the Balmer pseudocontinuum in spectra of type 1 AGNs. https://doi.org/10.1016/j.asr.2013.11.035

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