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Arp102B: An ADAF and a Torus ?

Ranga-Ram Chary
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Abstract

Arp102B is a nearby radio galaxy which displays the presence of double peaked Balmer emission lines. Sub-arcsec Keck mid-infrared imaging and Spitzer spectroscopy reveal a spatially compact mid-infrared source which displays tentative evidence for variability. The F$_ν\proptoν^{-1.2}$ spectral energy distribution is suggestive of an advection dominated accretion flow. The absence of dust features over the 5-40 micron range make it unlikely that thermal dust emission dominates the mid-infrared luminosity. We also detect the presence of molecular hydrogen in emission which is asymmetrically redshifted by ~500-1000 km/s from the systemic velocity of the galaxy. Since the forbidden, low ionization lines in this galaxy are at the systemic velocity, we suggest that the molecular hydrogen emission arises from a rotating molecular gas structure surrounding the nuclear black hole at a distance of ~1 pc.

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Ranga-Ram Chary. 2006-12-27. Arp102B: An ADAF and a Torus ?. https://arxiv.org/abs/astro-ph/0612737

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