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arXiv · 1312.0684

ALMA will determine the spectroscopic redshift z>8 with FIR [O III] emission lines

Akio K. Inoue·Ikkoh Shimizu·Yoichi Tamura·Hiroshi Matsuo·Takashi Okamoto·Naoki Yoshida
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Abstract

We investigate the potential use of nebular emission lines in the rest-frame far-infrared (FIR) for determining spectroscopic redshift of z>8 galaxies with the Atacama Large Millimeter/sub-millimeter Array (ALMA). After making a line emissivity model as a function of metallicity, especially for the [O III] 88 micron line which is likely to be the strongest FIR line from H II regions, we predict the line fluxes from high-z galaxies based on a cosmological hydrodynamics simulation of galaxy formation. Since the metallicity of galaxies reaches at ~0.2 Zsun even at z>8 in our simulation, we expect the [O III] 88 micron line as strong as 1.3 mJy for 27 AB objects, which is detectable at a high significance by <1 hour integration with ALMA. Therefore, the [O III] 88 micron line would be the best tool to confirm the spectroscopic redshifts beyond z=8.

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Akio K. Inoue, Ikkoh Shimizu, Yoichi Tamura, Hiroshi Matsuo, Takashi Okamoto, Naoki Yoshida. 2013-12-03. ALMA will determine the spectroscopic redshift z>8 with FIR [O III] emission lines. https://doi.org/10.1088/2041-8205/780/2/l18

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