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arXiv · 1701.00043

ALMA reveals Strong [CII] emission in a galaxy embedded in a giant Lyman-alpha blob at z=3.1

Hideki Umehata·Yuichi Matsuda·Yoichi Tamura·Kotaro Kohno·Ian Smail·R. J. Ivison·Charles C. Steidel·Scott C. Chapman·James E. Geach·Matthew Hayes·Tohru Nagao·Yiping Ao·Ryohei Kawabe·Min S. Yun·Bunyo Hatsukade·Mariko Kubo·Yuta Kato·Tomoki Saito·Soh Ikarashi·Kouichiro Nakanishi·Minju Lee·Takuma Izumi·Masao Mori·Masami Ouchi
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Abstract

We report the result from observations conducted with the Atacama Large Millimeter/submillimeter Array (ALMA) to detect [CII] 158 um fine structure line emission from galaxies embedded in one of the most spectacular Lyman-alpha blobs (LABs) at z=3.1, SSA22-LAB1. Of three dusty star-forming galaxies previously discovered by ALMA 860 um dust continuum survey toward SSA22-LAB1, we detected the [CII] line from one, LAB1-ALMA3 at z=3.0993+/-0.0004. No line emission was detected, associated with the other ALMA continuum sources or from three rest-frame UV/optical selected z_spec~3.1 galaxies within the field of view. For LAB1-ALMA3, we find relatively bright [CII] emission compared to the infrared luminosity (L_[CII]/L_[CII]) and an extremely high [CII] 158 um and [NII] 205 um emission line ratio (L_[CII]/L_[NII]>55). The relatively strong [CII] emission may be caused by abundant photodissociation regions and sub-solar metallicity, or by shock heating. The origin of the unusually strong [CII] emission could be causally related to the location within the giant LAB, although the relationship between extended Lyman-alpha emission and ISM conditions of associated galaxies is yet to be understand.

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Hideki Umehata, Yuichi Matsuda, Yoichi Tamura, Kotaro Kohno, Ian Smail, R. J. Ivison, Charles C. Steidel, Scott C. Chapman, James E. Geach, Matthew Hayes, Tohru Nagao, Yiping Ao, Ryohei Kawabe, Min S. Yun, Bunyo Hatsukade, Mariko Kubo, Yuta Kato, Tomoki Saito, Soh Ikarashi, Kouichiro Nakanishi, Minju Lee, Takuma Izumi, Masao Mori, Masami Ouchi. 2016-12-31. ALMA reveals Strong [CII] emission in a galaxy embedded in a giant Lyman-alpha blob at z=3.1. https://doi.org/10.3847/2041-8213%2F834%2F2%2Fl16

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