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Title: NIR SPECTROSCOPIC OBSERVATION OF MASSIVE GALAXIES IN THE PROTOCLUSTER AT z = 3.09

We present the results of near-infrared spectroscopic observations of the K-band-selected candidate galaxies in the protocluster at z = 3.09 in the SSA22 field. We observed 67 candidates with K {sub AB} < 24 and confirmed redshifts of the 39 galaxies at 2.0 < z {sub spec} < 3.4. Of the 67 candidates, 24 are certainly protocluster members with 3.04 ≤ z {sub spec} ≤ 3.12, which are massive red galaxies that have been unidentified in previous optical observations of the SSA22 protocluster. Many distant red galaxies (J – K {sub AB} > 1.4), hyper extremely red objects (J – K {sub AB} > 2.1), Spitzer MIPS 24 μm sources, active galactic nuclei (AGNs) as well as the counterparts of Lyα blobs and the AzTEC/ASTE 1.1 mm sources in the SSA22 field are also found to be protocluster members. The mass of the SSA22 protocluster is estimated to be ∼2-5 × 10{sup 14} M {sub ☉}, and this system is plausibly a progenitor of the most massive clusters of galaxies in the current universe. The reddest (J – K {sub AB} ≥ 2.4) protocluster galaxies are massive galaxies with M {sub star} ∼ 10{sup 11} M {sub ☉} showing quiescentmore » star formation activities and plausibly dominated by old stellar populations. Most of these massive quiescent galaxies host moderately luminous AGNs detected by X-ray. There are no significant differences in the [O III] λ5007/Hβ emission line ratios and [O III] λ5007 line widths and spatial extents of the protocluster galaxies from those of massive galaxies at z ∼ 2-3 in the general field.« less
Authors:
 [1] ; ;  [2] ;  [3] ;  [4] ;  [5]
  1. Institute for Cosmic Ray Research, University of Tokyo, 5-1-5 Kashiwa-no-Ha, Kashiwa City, Chiba 277-8582 (Japan)
  2. Astronomical Institute, Tohoku University, 6-3 Aoba, Aramaki, Aoba-ku, Sendai, Miyagi 980-8578 (Japan)
  3. Research Center for Space and Cosmic Evolution, Ehime University, Bunkyo-cho 2-5, Matsuyama 790-8577 (Japan)
  4. Chile Observatory, National Astronomical Observatory of Japan, Tokyo 181-8588 (Japan)
  5. Subaru Telescope, National Astronomical Observatory of Japan, 650 North Aohoku Place, Hilo, HI 96720 (United States)
Publication Date:
OSTI Identifier:
22364527
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 799; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; COSMOLOGY; GALAXIES; GALAXY CLUSTERS; GALAXY NUCLEI; LINE WIDTHS; MASS; PROTOSTARS; RED SHIFT; STAR EVOLUTION; STARS; UNIVERSE; X RADIATION