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Long-Term Profile Variability of Double-Peaked Emmission 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 arise from the outer regions of the accretion disk which fuels the AGN. The line profiles vary on timescales of 5--10 years. Our group has monitored a set of 20 double-peaked emitters for the past 8 years (longer for some objects). Here we describe a project to characterize the variability patterns of the double-peaked H alpha line profiles and compare with those of two simple models: a circular disk with a spiral arm and an elliptical disk.

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Karen T. Lewis, Michael Eracleous, Jules P. Halpern, Thaisa Storchi-Bergmann. 2004-04-16. Long-Term Profile Variability of Double-Peaked Emmission Lines in AGNs. https://doi.org/10.1017/s1743921304001668

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