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STIS spectroscopy of the emission line gas in the nuclei of nearby FR-I galaxies

Jacob Noel-Storr·Stefi A. Baum·Gijs Verdoes Kleijn·Roeland P. van der Marel·Christopher P. O'Dea·P. Tim de Zeeuw·C. Marcella Carollo
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Abstract

We present the results of the analysis of a set of medium resolution spectra, obtained by the Space Telescope Imaging Spectrograph on board the Hubble Space Telescope, of the emission line gas present in the nuclei of a complete sample of 21 nearby, early-type galaxies with radio jets (the UGC FR-I Sample). For each galaxy nucleus we present spectroscopic data in the region of H-alpha and the dervived kinematics. We find that in 67% of the nuclei the gas appears to be rotating and, with one exception, the cases where rotation is not seen are either face on or have complex central morphologies. We find that in 62% of the nuclei the fit to the central spectrum is improved by the inclusion of a broad component. The broad components have a mean velocity dispersion of 1349 +/- 345 km\s and are redshifted from the narrow line components (assuming an origin in H-alpha) by 486 +/- 443 km\s.

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Jacob Noel-Storr, Stefi A. Baum, Gijs Verdoes Kleijn, Roeland P. van der Marel, Christopher P. O'Dea, P. Tim de Zeeuw, C. Marcella Carollo. 2003-06-02. STIS spectroscopy of the emission line gas in the nuclei of nearby FR-I galaxies. https://doi.org/10.1086/377251

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