Publications of The Korean Astronomical Society (천문학논총)

The Korean Astronomical Society (한국천문학회)
권호 표지
DOI QR코드

DOI QR Code

THE 18 ㎛ LUMINOSITY FUNCTION OF GALAXIES WITH AKARI

  • Toba, Yoshiki (Department of Space and Astronautical Science, the Graduate University for Advanced Studies (Sokendai)) ;
  • Oyabu, Shinki (Graduate School of Science, Nagoya University) ;
  • Matsuhara, Hideo (Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency) ;
  • Ishihara, Daisuke (Graduate School of Science, Nagoya University) ;
  • Malkan, Matt (Department of Physics and Astronomy, University of California) ;
  • Wada, Takehiko (Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency) ;
  • Ohyama, Youichi (Academia Sinica, Institute of Astronomy and Astrophysics) ;
  • Kataza, Hirokazu (Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency) ;
  • Takita, Satoshi (Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency)
  • Received : 2012.06.30
  • Accepted : 2012.08.02
  • Published : 2012.09.16
Download PDF
⟨ Previous Next ⟩

Abstract

We present the $18{\mu}m$ luminosity function (LF) of galaxies at 0.006 < z < 0.8 (the average redshift is ~ 0.04) using the AKARI mid-infrared All-Sky Survey catalogue. We have selected 243 galaxies at $18{\mu}m$ from the Sloan Digital Sky Survey (SDSS) spectroscopic region. These galaxies then have been classified into five types; Seyfert 1 galaxies (Sy1, including quasars), Seyfert 2 galaxies (Sy2), low ionization narrow emission line galaxies (LINER), galaxies that are likely to contain both star formation and Active Galactic Nuclei (AGN) activities (composites), and star forming galaxies (SF) using optical emission lines such as the line width of $H{\alpha}$ or the emission line ratios of [OIII]/$H{\beta}$ and [NII]/$H{\alpha}$. As a result of constructing the LF of Sy1 and Sy2, we found the following results; (i) the number density ratio of Sy2 to Sy1 is $1.64{\pm}0.37$, larger than the results obtained from optical LF and (ii) the fraction of Sy2 in the entire AGN population may decrease with $18{\mu}m$ luminosity. These results suggest that most of the AGNs in the local universe are obscured by dust and the torus structure probably depends on the mid-infrared luminosity.

Keywords

References

  1. Abazajian, K. N., et al., 2009, The Seventh Data Release of the Sloan Digital Sky Survey, ApJS, 182, 543 https://doi.org/10.1088/0067-0049/182/2/543
  2. Baldwin, J. A., Phillips, M. M., & Terlevich, R., 1981, Classification Parameters for the Emission-Line Spectra of Extragalactic Objects, PASP, 93, 5 https://doi.org/10.1086/130766
  3. Burlon, D., et al., 2011, Three-year Swift-BAT Survey of Active Galactic Nuclei: Reconciling Theory and Observations?, AJ, 728, 58 https://doi.org/10.1088/0004-637X/728/1/58
  4. Dye, S., et al., 2010, Herschel-ATLAS: Evolution of the 250 ${\mu}m$ Luminosity Function out to z = 0.5, A&A, 518, L10 https://doi.org/10.1051/0004-6361/201014614
  5. Fang, F., Shupe, D. L., Xu, C., & Hacking, P. B., 1998, The Mid-Infrared Color-Luminosity Relation and the Local 12 Micron Luminosity Function, AJ, 500, 693 https://doi.org/10.1086/305761
  6. Hao, L., et al., 2005, Active Galactic Nuclei in the Sloan Digital Sky Survey. II. Emission-Line Luminosity Function, AJ, 129, 1795 https://doi.org/10.1086/428486
  7. Hao, L., et al., 2005, Active Galactic Nuclei in the Sloan Digital Sky Survey. I. Sample Selection, AJ, 129, 1783 https://doi.org/10.1086/428485
  8. Huchra, J. P., Geller, M. J., & Corwin, H. G., Jr., 1995, The CfA Redshift Survey: Data for the NGP +36 Zone, ApJS, 99, 391 https://doi.org/10.1086/192191
  9. Ishihara, D., et al., 2010, The AKARI/IRC Mid- Infrared All-Sky Survey, A&A, 514, 1
  10. Kataza, H., et al., 2010, AKARI/IRC Point Source Catalogue Version 1.0 -Release Note (Rev.1)
  11. Lutz, D., Maiolino, R., Spoon, H. W. W., & Moorwood, A. F. M., 2004, The Relation between AGN Hard X-Ray Emission and Mid-Infrared Continuum from ISO Spectra: Scatter and Unification Aspects, A&A, 418, 465 https://doi.org/10.1051/0004-6361:20035838
  12. Lawrence, A., 1991, The Relative Frequency of Broad- Lined and Narrow-Lined Active Galactic Nuclei - Implications for Unified Schemes, MNRAS, 252, 586 https://doi.org/10.1093/mnras/252.4.586
  13. Malizia, A., et al., 2009, The Fraction of Compton- Thick Sources in an INTEGRAL Complete AGN Sample, MNRAS, 399, 944 https://doi.org/10.1111/j.1365-2966.2009.15330.x
  14. Pozzi, F., et al., 2004, The Mid-Infrared Luminosity Function of Galaxies in the European Large Area Infrared Space Observatory Survey Southern Fields, AJ, 609, 122 https://doi.org/10.1086/420963
  15. Rodighiero, G., et al., 2010, Mid- and Far-Infrared Luminosity Functions and Galaxy Evolution from Multiwavelength Spitzer Observations up to z 2.5, A&A, 515, 8 https://doi.org/10.1051/0004-6361/200912058
  16. Rush, B., Malkan, M. A., & Spinoglio, L., 1993, The Extended 12 Micron Galaxy Sample, ApJS, 89, 1 https://doi.org/10.1086/191837
  17. Saunders, W., et al., 1990, The 60-Micron and Far- Infrared Luminosity Functions of IRAS Galaxies, MNRAS, 242, 318 https://doi.org/10.1093/mnras/242.3.318
  18. Schmidt, M., 1968, Space Distribution and Luminosity Functions of Quasi-Stellar Radio Sources, AJ, 151, 393 https://doi.org/10.1086/149446
  19. Shang, Z., et al., 2011, The Next Generation Atlas of Quasar Spectral Energy Distributions from Radio to X-Rays, ApJS 196, 2 https://doi.org/10.1088/0067-0049/196/1/2
  20. Yamamura, I., et al., 2010, AKARI/FIS All-Sky Survey Point Source Catalogues (ISAS/JAXA, 2010), yCat, 2298, 0