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Gas Disks and Supermassive Black Holes in Nearby Radio Galaxies

Gas Disks and Supermassive Black Holes in Nearby Radio Galaxies

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Abstract<br />

<strong>Gas</strong> <strong>Disks</strong> <strong>and</strong> <strong>Supermassive</strong> <strong>Black</strong> <strong>Holes</strong> <strong>in</strong> <strong>Nearby</strong> <strong>Radio</strong> <strong>Galaxies</strong><br />

Jacob Noel-Storr<br />

We present a detailed analysis of a set of medium resolution spectra, obta<strong>in</strong>ed by<br />

the Space Telescope Imag<strong>in</strong>g Spectrograph on board the Hubble Space Telescope, of<br />

the emission l<strong>in</strong>e gas present <strong>in</strong> the nuclei of a complete sample of 21 nearby, early-type<br />

galaxies with radio jets (the UGC FR-I sample). For each galaxy nucleus we present<br />

spectroscopic data <strong>in</strong> the region of Hydrogen-alpha <strong>and</strong> the derived k<strong>in</strong>ematics.<br />

We f<strong>in</strong>d that is 67% of the nuclei the gas appears to be rotat<strong>in</strong>g <strong>and</strong>, with one<br />

exception, the cases where rotation is not seen are either face on or have complex<br />

central morphologies. We f<strong>in</strong>d that <strong>in</strong> 62% of the nuclei the fit to the central spectrum<br />

is improved by the <strong>in</strong>clusion of a broad component. The broad components have a<br />

mean velocity dispersion of 1349 ± 345 km s −1 <strong>and</strong> are redshifted from the narrow<br />

l<strong>in</strong>e components (assum<strong>in</strong>g an orig<strong>in</strong> <strong>in</strong> Hydrogen-alpha) by 486 ± 443 km s −1 .<br />

We generated model velocity profiles for the nuclei <strong>in</strong>clud<strong>in</strong>g no black hole, a<br />

1 × 10 8 solar mass black hole <strong>and</strong> a 9 × 10 8 solar mass black hole. We compared the

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