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Title: OPTICAL–INFRARED PROPERTIES OF FAINT 1.3 mm SOURCES DETECTED WITH ALMA

Abstract

We report optical-infrared (IR) properties of faint 1.3 mm sources (S{sub 1.3mm} = 0.2–1.0 mJy) detected with the Atacama Large Millimeter/submillimeter Array (ALMA) in the Subaru/XMM-Newton Deep Survey field. We searched for optical/IR counterparts of eight ALMA-detected sources (≥4.0σ, the sum of the probability of spurious source contamination is ∼1) in a K-band source catalog. Four ALMA sources have K-band counterpart candidates within a 0.″4 radius. Comparison between ALMA-detected and undetected K-band sources in the same observing fields shows that ALMA-detected sources tend to be brighter, more massive, and more actively forming stars. While many of the ALMA-identified submillimeter-bright galaxies (SMGs) in previous studies lie above the sequence of star-forming galaxies in the stellar mass–star formation rate plane, our ALMA sources are located in the sequence, suggesting that the ALMA-detected faint sources are more like “normal” star-forming galaxies rather than “classical” SMGs. We found a region where multiple ALMA sources and K-band sources reside in a narrow photometric redshift range (z ∼ 1.3–1.6) within a radius of 5″ (42 kpc if we assume z = 1.45). This is possibly a pre-merging system and we may be witnessing the early phase of formation of a massive elliptical galaxy.

Authors:
;  [1]; ;  [2];  [3];  [4]
  1. National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan)
  2. Department of Astronomy, Kyoto University, Kyoto 606-8502 (Japan)
  3. Institute of Astronomy, University of Tokyo, 2-21-1 Osawa, Mitaka, Tokyo 181-0015 (Japan)
  4. Astronomical Institute, Tohoku University, Aramaki, Aoba-ku, Sendai, Miyagi 980-8578 (Japan)
Publication Date:
OSTI Identifier:
22525473
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 810; 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; COMPARATIVE EVALUATIONS; COSMOLOGY; GALACTIC EVOLUTION; GALAXIES; MASS; PROBABILITY; RED SHIFT; STAR EVOLUTION; STARS

Citation Formats

Hatsukade, Bunyo, Yabe, Kiyoto, Ohta, Kouji, Seko, Akifumi, Makiya, Ryu, and Akiyama, Masayuki, E-mail: bunyo.hatsukade@nao.ac.jp. OPTICAL–INFRARED PROPERTIES OF FAINT 1.3 mm SOURCES DETECTED WITH ALMA. United States: N. p., 2015. Web. doi:10.1088/0004-637X/810/2/91.
Hatsukade, Bunyo, Yabe, Kiyoto, Ohta, Kouji, Seko, Akifumi, Makiya, Ryu, & Akiyama, Masayuki, E-mail: bunyo.hatsukade@nao.ac.jp. OPTICAL–INFRARED PROPERTIES OF FAINT 1.3 mm SOURCES DETECTED WITH ALMA. United States. doi:10.1088/0004-637X/810/2/91.
Hatsukade, Bunyo, Yabe, Kiyoto, Ohta, Kouji, Seko, Akifumi, Makiya, Ryu, and Akiyama, Masayuki, E-mail: bunyo.hatsukade@nao.ac.jp. 2015. "OPTICAL–INFRARED PROPERTIES OF FAINT 1.3 mm SOURCES DETECTED WITH ALMA". United States. doi:10.1088/0004-637X/810/2/91.
@article{osti_22525473,
title = {OPTICAL–INFRARED PROPERTIES OF FAINT 1.3 mm SOURCES DETECTED WITH ALMA},
author = {Hatsukade, Bunyo and Yabe, Kiyoto and Ohta, Kouji and Seko, Akifumi and Makiya, Ryu and Akiyama, Masayuki, E-mail: bunyo.hatsukade@nao.ac.jp},
abstractNote = {We report optical-infrared (IR) properties of faint 1.3 mm sources (S{sub 1.3mm} = 0.2–1.0 mJy) detected with the Atacama Large Millimeter/submillimeter Array (ALMA) in the Subaru/XMM-Newton Deep Survey field. We searched for optical/IR counterparts of eight ALMA-detected sources (≥4.0σ, the sum of the probability of spurious source contamination is ∼1) in a K-band source catalog. Four ALMA sources have K-band counterpart candidates within a 0.″4 radius. Comparison between ALMA-detected and undetected K-band sources in the same observing fields shows that ALMA-detected sources tend to be brighter, more massive, and more actively forming stars. While many of the ALMA-identified submillimeter-bright galaxies (SMGs) in previous studies lie above the sequence of star-forming galaxies in the stellar mass–star formation rate plane, our ALMA sources are located in the sequence, suggesting that the ALMA-detected faint sources are more like “normal” star-forming galaxies rather than “classical” SMGs. We found a region where multiple ALMA sources and K-band sources reside in a narrow photometric redshift range (z ∼ 1.3–1.6) within a radius of 5″ (42 kpc if we assume z = 1.45). This is possibly a pre-merging system and we may be witnessing the early phase of formation of a massive elliptical galaxy.},
doi = {10.1088/0004-637X/810/2/91},
journal = {Astrophysical Journal},
number = 2,
volume = 810,
place = {United States},
year = 2015,
month = 9
}
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