Long Term Profile Variability of Double-Peaked Emission Lines in AGNs

Karen T. Lewis; Michael Eracleous; Jules P. Halpern; Thaisa Storchi-Bergmann

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Long Term Profile Variability of Double-Peaked Emission Lines in AGNs

Karen T. Lewis·Michael Eracleous·Jules P. Halpern·Thaisa Storchi-Bergmann

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Abstract

An increasing number of AGNs exhibit broad, double-peaked Balmer emission lines, which are thought to arise from the outer regions of the accretion disk which fuels the AGN. The line profiles are observed to vary on a characteristic timescales of 5-10 years. The variability is not a reverberation effect; it is a manifestation of physical changes in the disk. Our group has monitored a set of 20 double-peaked emitters for the past 8 years (longer for some objects). Here, we characterize the variability of the double-peaked H alpha line profiles in five objects from our sample. By experimenting with simple models, we find that disks with a single precessing spiral arm are able to reproduce many of the variability trends that are seen in the data.

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Karen T. Lewis, Michael Eracleous, Jules P. Halpern, Thaisa Storchi-Bergmann. 2003-09-23. Long Term Profile Variability of Double-Peaked Emission Lines in AGNs. https://arxiv.org/abs/astro-ph/0309624

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