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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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organized rotation. This supports the picture described above, <strong>and</strong> the view that<br />

dispersive effects are less efficient perpendicular to the plane of the disk, so settl<strong>in</strong>g<br />

may be slow, which supports the picture we developed for the nuclei of these galaxies<br />

<strong>in</strong> Chapter 4.<br />

Compar<strong>in</strong>g to the central stellar velocity dispersion, as discussed <strong>in</strong> Chapters 1<br />

<strong>and</strong> 2, we found that the stellar velocity dispersion <strong>and</strong> the gas velocity dispersions<br />

are closely related, imply<strong>in</strong>g that the stellar dispersion drives some of the r<strong>and</strong>om<br />

motions <strong>in</strong> the gas. This has possible implications for fuel<strong>in</strong>g of the black hole, <strong>and</strong><br />

connections between the stellar velocity dispersion <strong>and</strong> central eng<strong>in</strong>e.<br />

We presented some evidence that the broad components used <strong>in</strong> earlier fits (Chap-<br />

ter 3) may orig<strong>in</strong>ate from physical broad-l<strong>in</strong>e regions <strong>in</strong> the galaxy. We also showed<br />

that newly obta<strong>in</strong>ed X-ray fluxes are correlated with other fluxes <strong>in</strong> the nuclear re-<br />

gions, extend<strong>in</strong>g the correlations found by Verdoes Kleijn et al. (2002a) to a new<br />

wavelength regime. F<strong>in</strong>ally we found correlations between the broad l<strong>in</strong>e width <strong>and</strong><br />

the VLBA <strong>and</strong> X-ray lum<strong>in</strong>osities <strong>in</strong>dicat<strong>in</strong>g that the activity of the central eng<strong>in</strong>e<br />

may be responsible for driv<strong>in</strong>g a large component of the dispersion <strong>in</strong> this gas, rather<br />

than it be<strong>in</strong>g due to gravitational motion around the black hole. As we cannot con-<br />

firm that the M• − σc relation applies to all radio galaxies, we can not determ<strong>in</strong>e if<br />

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