English

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

Astrophysics of Galaxies 2015-12-08 v1

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 (z<0.05\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 and >20%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_{\sun} yr1^{-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 \sim3x lower SFR. Using GALFIT to measure the size of the FIR emitting regions, we determined the SFR surface density [M\sun_{\sun} yr1^{-1} kpc2^{-2}] for our sample, finding a significant fraction of these sources exceed the threshold for star formation driven winds (0.1 M\sun_{\sun} yr1^{-1} kpc2^{-2}).

Keywords

Cite

@article{arxiv.1312.7766,
  title  = {Do Most Active Galactic Nuclei Live in High Star Formation Nuclear Cusps?},
  author = {Richard F. Mushotzky and T. Taro Shimizu and Marcio Melendez and Michael Koss},
  journal= {arXiv preprint arXiv:1312.7766},
  year   = {2015}
}

Comments

5 pages, 5 figures, accepted for publication in ApJ Letters

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