Variability in LINERs
نویسنده
چکیده
A small number of LINERs have been seen to display variable Hα emission with a very broad, double-peaked profile. Recent observations with the Hubble Space Telescope indicate that such emission may be a common attribute of LINERs. The double-peaked or doubleshouldered line profiles resemble those found in a subset of broad-line radio galaxies. Several lines of argument suggest that such features trace an outer thin accretion disk irradiated by an inner ion torus, in accord with advection-dominated accretion flow (ADAF) models. Variability monitoring of this broad Hα component thus may provide a means of testing accretion physics on small scales within these sources.
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