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arXiv · 1312.7766

Do Most Active Galactic Nuclei Live in High Star Formation Nuclear Cusps?

Richard F. Mushotzky·T. Taro Shimizu·Marcio Melendez·Michael Koss
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Abstract

We present early results of the Herschel PACS (70 and 160 \micron{}) and SPIRE (250, 350, and 500 \micron{}) survey of 313 low redshift ($\rm{z} < 0.05$), ultra-hard X-ray (14--195 keV) selected AGN from the 58 month Swift/BAT catalog. Selection of AGN from ultra-hard X-rays avoids bias from obscuration providing a complete sample of AGN to study the connection between nuclear activity and star formation in host galaxies. With the high angular resolution of PACS, we find that $>$35\%$ and $>$20\%$ of the sources are "point-like" at 70 and 160 \micron{} respectively and many more that have their flux dominated by a point source located at the nucleus. The inferred star formation rates (SFR) of 0.1 - 100 M$_{\sun}$ yr$^{-1}$ using the 70 and 160 \micron{} flux densities as SFR indicators are consistent with those inferred from Spitzer NeII fluxes, but we find that 11.25 \micron{} PAH data give $\sim$3x lower SFR. Using GALFIT to measure the size of the FIR emitting regions, we determined the SFR surface density [M$_{\sun}$ yr$^{-1}$ kpc$^{-2}$] for our sample, finding a significant fraction of these sources exceed the threshold for star formation driven winds (0.1 M$_{\sun}$ yr$^{-1}$ kpc$^{-2}$).

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Richard F. Mushotzky, T. Taro Shimizu, Marcio Melendez, Michael Koss. 2013-12-30. Do Most Active Galactic Nuclei Live in High Star Formation Nuclear Cusps?. https://doi.org/10.1088/2041-8205%2F781%2F2%2Fl34

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