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Title: WIDESPREAD AND HIDDEN ACTIVE GALACTIC NUCLEI IN STAR-FORMING GALAXIES AT REDSHIFT >0.3

Abstract

We characterize the incidence of active galactic nuclei (AGNs) in 0.3 < z < 1 star-forming galaxies by applying multi-wavelength AGN diagnostics (X-ray, optical, mid-infrared, radio) to a sample of galaxies selected at 70 {mu}m from the Far-Infrared Deep Extragalactic Legacy survey (FIDEL). Given the depth of FIDEL, we detect 'normal' galaxies on the specific star formation rate (sSFR) sequence as well as starbursting systems with elevated sSFR. We find an overall high occurrence of AGN of 37% {+-} 3%, more than twice as high as in previous studies of galaxies with comparable infrared luminosities and redshifts but in good agreement with the AGN fraction of nearby (0.05 < z < 0.1) galaxies of similar infrared luminosities. The more complete census of AGNs comes from using the recently developed Mass-Excitation (MEx) diagnostic diagram. This optical diagnostic is also sensitive to X-ray weak AGNs and X-ray absorbed AGNs, and reveals that absorbed active nuclei reside almost exclusively in infrared-luminous hosts. The fraction of galaxies hosting an AGN appears to be independent of sSFR and remains elevated both on the sSFR sequence and above. In contrast, the fraction of AGNs that are X-ray absorbed increases substantially with increasing sSFR, possibly due tomore » an increased gas fraction and/or gas density in the host galaxies.« less

Authors:
; ; ;  [1]; ;  [2]; ;  [3];  [4]; ;  [5];  [6];  [7]; ; ;  [8]; ;  [9];  [10];  [11] more »; « less
  1. CEA-Saclay, DSM/IRFU/SAp, F-91191 Gif-sur-Yvette (France)
  2. National Optical Astronomy Observatory, 950 North Cherry Avenue, Tucson, AZ 85719 (United States)
  3. Department of Physics, Durham University, Durham DH1 3LE (United Kingdom)
  4. Max-Planck-Instituet fuer extraterrestrische Physik, Postfach 1312, D-85741 Garching bei Muenchen (Germany)
  5. Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)
  6. Department of Physics, Center for Astrophysics and Space Sciences, University of California, 9500 Gilman Dr., La Jolla, San Diego, CA 92093 (United States)
  7. Max-Planck-Instituet fuer extraterrestrische Physik, Giessenbachstrasse, D-85748 Garching bei Muenchen (Germany)
  8. University of California Observatories/Lick Observatory, University of California, Santa Cruz, CA 95064 (United States)
  9. Steward Observatory, University of Arizona, Tucson, AZ 85721 (United States)
  10. Center for Galaxy Evolution, Department of Physics and Astronomy, University of California-Irvine, 4129 Frederick Reines Hall, Irvine, CA 92697 (United States)
  11. National Radio Astronomy Observatory, P.O. Box 2, Green Bank, WV 24944 (United States)
Publication Date:
OSTI Identifier:
22167695
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 764; 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; ASTRONOMY; ASTROPHYSICS; COMPARATIVE EVALUATIONS; DENSITY; DIAGRAMS; EXCITATION; GALACTIC EVOLUTION; GALAXIES; GALAXY NUCLEI; LUMINOSITY; MASS; RED SHIFT; STAR EVOLUTION; STARS; X RADIATION

Citation Formats

Juneau, Stephanie, Bournaud, Frederic, Daddi, Emanuele, Elbaz, David, Dickinson, Mark, Kartaltepe, Jeyhan S., Alexander, David M., Mullaney, James R., Magnelli, Benjamin, Hwang, Ho Seong, Willner, S. P., Coil, Alison L., Rosario, David J., Trump, Jonathan R., Faber, S. M., Kocevski, Dale D., Weiner, Benjamin J., Willmer, Christopher N. A., Cooper, Michael C., Frayer, David T., E-mail: stephanie.juneau@cea.fr, and and others. WIDESPREAD AND HIDDEN ACTIVE GALACTIC NUCLEI IN STAR-FORMING GALAXIES AT REDSHIFT >0.3. United States: N. p., 2013. Web. doi:10.1088/0004-637X/764/2/176.
Juneau, Stephanie, Bournaud, Frederic, Daddi, Emanuele, Elbaz, David, Dickinson, Mark, Kartaltepe, Jeyhan S., Alexander, David M., Mullaney, James R., Magnelli, Benjamin, Hwang, Ho Seong, Willner, S. P., Coil, Alison L., Rosario, David J., Trump, Jonathan R., Faber, S. M., Kocevski, Dale D., Weiner, Benjamin J., Willmer, Christopher N. A., Cooper, Michael C., Frayer, David T., E-mail: stephanie.juneau@cea.fr, & and others. WIDESPREAD AND HIDDEN ACTIVE GALACTIC NUCLEI IN STAR-FORMING GALAXIES AT REDSHIFT >0.3. United States. doi:10.1088/0004-637X/764/2/176.
Juneau, Stephanie, Bournaud, Frederic, Daddi, Emanuele, Elbaz, David, Dickinson, Mark, Kartaltepe, Jeyhan S., Alexander, David M., Mullaney, James R., Magnelli, Benjamin, Hwang, Ho Seong, Willner, S. P., Coil, Alison L., Rosario, David J., Trump, Jonathan R., Faber, S. M., Kocevski, Dale D., Weiner, Benjamin J., Willmer, Christopher N. A., Cooper, Michael C., Frayer, David T., E-mail: stephanie.juneau@cea.fr, and and others. 2013. "WIDESPREAD AND HIDDEN ACTIVE GALACTIC NUCLEI IN STAR-FORMING GALAXIES AT REDSHIFT >0.3". United States. doi:10.1088/0004-637X/764/2/176.
@article{osti_22167695,
title = {WIDESPREAD AND HIDDEN ACTIVE GALACTIC NUCLEI IN STAR-FORMING GALAXIES AT REDSHIFT >0.3},
author = {Juneau, Stephanie and Bournaud, Frederic and Daddi, Emanuele and Elbaz, David and Dickinson, Mark and Kartaltepe, Jeyhan S. and Alexander, David M. and Mullaney, James R. and Magnelli, Benjamin and Hwang, Ho Seong and Willner, S. P. and Coil, Alison L. and Rosario, David J. and Trump, Jonathan R. and Faber, S. M. and Kocevski, Dale D. and Weiner, Benjamin J. and Willmer, Christopher N. A. and Cooper, Michael C. and Frayer, David T., E-mail: stephanie.juneau@cea.fr and and others},
abstractNote = {We characterize the incidence of active galactic nuclei (AGNs) in 0.3 < z < 1 star-forming galaxies by applying multi-wavelength AGN diagnostics (X-ray, optical, mid-infrared, radio) to a sample of galaxies selected at 70 {mu}m from the Far-Infrared Deep Extragalactic Legacy survey (FIDEL). Given the depth of FIDEL, we detect 'normal' galaxies on the specific star formation rate (sSFR) sequence as well as starbursting systems with elevated sSFR. We find an overall high occurrence of AGN of 37% {+-} 3%, more than twice as high as in previous studies of galaxies with comparable infrared luminosities and redshifts but in good agreement with the AGN fraction of nearby (0.05 < z < 0.1) galaxies of similar infrared luminosities. The more complete census of AGNs comes from using the recently developed Mass-Excitation (MEx) diagnostic diagram. This optical diagnostic is also sensitive to X-ray weak AGNs and X-ray absorbed AGNs, and reveals that absorbed active nuclei reside almost exclusively in infrared-luminous hosts. The fraction of galaxies hosting an AGN appears to be independent of sSFR and remains elevated both on the sSFR sequence and above. In contrast, the fraction of AGNs that are X-ray absorbed increases substantially with increasing sSFR, possibly due to an increased gas fraction and/or gas density in the host galaxies.},
doi = {10.1088/0004-637X/764/2/176},
journal = {Astrophysical Journal},
number = 2,
volume = 764,
place = {United States},
year = 2013,
month = 2
}
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