Program: GS-2010A-Q-81

The first LINER observed with a double-peaked Halpha emission line from its nucleus was NGC1097, in November 1991. After that, we have followed the Halpha broad component for 10 years. These data have allowed us to measure the variations of its profile which were used to constrain the properties of the accretion flow (which is believed to be the origin of the double-peaked line) around the nuclear supermassive black hole,. These properties are the inner and outer radii of the accretion disk and its emissivity. Since then, other LINERs were found to present similar double-peaked profliles, suggesting that these objects should have similiar variability. The goals of this proposal are: (1) to obtain aditional spectra of the nucleus of the NGC1097 to constrain the properties of the accretion disk and compare then with those derived in our previous works, (2) observe, for the first time, the nuclear spectrum of another LINER, NGC7213, which shows also similar double-peaked Halpha proflile to the one observed in NGC1097. We propose, for both objects, to use the long-slit mode of GMOS-N and the same setup used in a previous similar proposal. This proposal is adequate for poor weather.