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DETECTION OF Hα EMISSION FROM z>3.5 GALAXIES WITH AKARI-FUHYU NIR SPECTROSCOPY

  • Sedgwick, Chris (Department of Physical Sciences, The Open University) ;
  • Serjeant, Stephen (Department of Physical Sciences, The Open University) ;
  • Pearson, Chris (RAL Space, Rutherford Appleton Laboratory) ;
  • Takagi, Toshinobu (Institute of Space and Astronautical Science, JAXA) ;
  • Matsuhara, Hideo (Institute of Space and Astronautical Science, JAXA) ;
  • Wada, Takehiko (Institute of Space and Astronautical Science, JAXA) ;
  • Lee, Hyung Mok (Department of Physics and Astronomy, Seoul National University) ;
  • Im, Myungshin (Department of Physics and Astronomy, Seoul National University) ;
  • Jeong, Woong-Seob (Korea Astronomy & Space Science Institute) ;
  • Oyabu, Shinki (Graduate School of Science, Nagoya University) ;
  • White, Glenn J. (Department of Physical Sciences, The Open University)
  • Received : 2012.07.01
  • Accepted : 2012.08.15
  • Published : 2012.09.16

Abstract

This paper presents $H{\alpha}$ emission line detections for four galaxies at z > 3.5 made with AKARI as part of the FUHYU mission program. These are the highest-redshift $H{\alpha}$ detections to date in star-forming galaxies. AKARI's unique near-infrared spectroscopic capability has made these detections possible. For two of these galaxies, this represents the first evidence of their redshifts and confirms their physical association with a companion radio galaxy. The star formation rates (SFRs) estimated from the $H{\alpha}$ lines under-predict the SFRs estimated from their far-infrared luminosities by a factor of ~ 2 - 3. We have also detected broad $H{\alpha}$ components in the two radio galaxies which indicate the presence of quasars.

Keywords

References

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