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Title: DO MOST ACTIVE GALACTIC NUCLEI LIVE IN HIGH STAR FORMATION NUCLEAR CUSPS?

Abstract

We present early results of the Herschel PACS (70 and 160 μm) and SPIRE (250, 350, and 500 μm) survey of 313 low redshift (z < 0.05), ultra-hard X-ray (14-195 keV) selected active galactic nuclei (AGNs) from the 58 month Swift/Burst Alert Telescope catalog. Selection of AGNs from ultra-hard X-rays avoids bias from obscuration, providing a complete sample of AGNs 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 μm respectively and many more have their flux dominated by a point source located at the nucleus. The inferred star formation rates (SFRs) of 0.1-100 M {sub ☉} yr{sup –1} using the 70 and 160 μm flux densities as SFR indicators are consistent with those inferred from Spitzer Ne II fluxes, but we find that 11.25 μm polycyclic aromatic hydrocarbon data give ∼3× lower SFR. Using GALFIT to measure the size of the far-infrared emitting regions, we determined the SFR surface density (M {sub ☉} yr{sup –1} kpc{sup –2}) for our sample, finding that a significant fraction of these sources exceed the threshold for star formation driven winds (0.1 M {submore » ☉} yr{sup –1} kpc{sup –2})« less

Authors:
; ;  [1];  [2]
  1. Department of Astronomy, University of Maryland, College Park, MD 20742 (United States)
  2. Institute for Astronomy, University of Hawaii, Honolulu, HI 96822 (United States)
Publication Date:
OSTI Identifier:
22364010
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal Letters; Journal Volume: 781; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; CATALOGS; FLUX DENSITY; GALAXIES; GALAXY NUCLEI; HARD X RADIATION; INDICATORS; KEV RANGE; POLYCYCLIC AROMATIC HYDROCARBONS; RED SHIFT; RESOLUTION; STARS; STELLAR WINDS; SURFACES; TELESCOPES

Citation Formats

Mushotzky, Richard F., Shimizu, T. Taro, Meléndez, Marcio, and Koss, Michael, E-mail: richard@astro.umd.edu. DO MOST ACTIVE GALACTIC NUCLEI LIVE IN HIGH STAR FORMATION NUCLEAR CUSPS?. United States: N. p., 2014. Web. doi:10.1088/2041-8205/781/2/L34.
Mushotzky, Richard F., Shimizu, T. Taro, Meléndez, Marcio, & Koss, Michael, E-mail: richard@astro.umd.edu. DO MOST ACTIVE GALACTIC NUCLEI LIVE IN HIGH STAR FORMATION NUCLEAR CUSPS?. United States. doi:10.1088/2041-8205/781/2/L34.
Mushotzky, Richard F., Shimizu, T. Taro, Meléndez, Marcio, and Koss, Michael, E-mail: richard@astro.umd.edu. 2014. "DO MOST ACTIVE GALACTIC NUCLEI LIVE IN HIGH STAR FORMATION NUCLEAR CUSPS?". United States. doi:10.1088/2041-8205/781/2/L34.
@article{osti_22364010,
title = {DO MOST ACTIVE GALACTIC NUCLEI LIVE IN HIGH STAR FORMATION NUCLEAR CUSPS?},
author = {Mushotzky, Richard F. and Shimizu, T. Taro and Meléndez, Marcio and Koss, Michael, E-mail: richard@astro.umd.edu},
abstractNote = {We present early results of the Herschel PACS (70 and 160 μm) and SPIRE (250, 350, and 500 μm) survey of 313 low redshift (z < 0.05), ultra-hard X-ray (14-195 keV) selected active galactic nuclei (AGNs) from the 58 month Swift/Burst Alert Telescope catalog. Selection of AGNs from ultra-hard X-rays avoids bias from obscuration, providing a complete sample of AGNs 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 μm respectively and many more have their flux dominated by a point source located at the nucleus. The inferred star formation rates (SFRs) of 0.1-100 M {sub ☉} yr{sup –1} using the 70 and 160 μm flux densities as SFR indicators are consistent with those inferred from Spitzer Ne II fluxes, but we find that 11.25 μm polycyclic aromatic hydrocarbon data give ∼3× lower SFR. Using GALFIT to measure the size of the far-infrared emitting regions, we determined the SFR surface density (M {sub ☉} yr{sup –1} kpc{sup –2}) for our sample, finding that a significant fraction of these sources exceed the threshold for star formation driven winds (0.1 M {sub ☉} yr{sup –1} kpc{sup –2})},
doi = {10.1088/2041-8205/781/2/L34},
journal = {Astrophysical Journal Letters},
number = 2,
volume = 781,
place = {United States},
year = 2014,
month = 2
}
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