Hodge J A, da Cunha E
Leiden Observatory, Leiden University, PO Box 9513, 2300 RA Leiden, The Netherlands.
International Centre for Radio Astronomy Research, University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia.
R Soc Open Sci. 2020 Dec 9;7(12):200556. doi: 10.1098/rsos.200556. eCollection 2020 Dec.
The Atacama Large Millimetre/submillimetre Array (ALMA) is currently in the process of transforming our view of star-forming galaxies in the distant ( ) universe. Before ALMA, most of what we knew about dust-obscured star formation in distant galaxies was limited to the brightest submillimetre sources-the so-called submillimetre galaxies (SMGs)-and even the information on those sources was sparse, with resolved (i.e. sub-galactic) observations of the obscured star formation and gas reservoirs typically restricted to the most extreme and/or strongly lensed sources. Starting with the beginning of early science operations in 2011, the last 9 years of ALMA observations have ushered in a new era for studies of high-redshift star formation. With its long baselines, ALMA has allowed observations of distant dust-obscured star formation with angular resolutions comparable to-or even far surpassing-the best current optical telescopes. With its bandwidth and frequency coverage, it has provided an unprecedented look at the associated molecular and atomic gas in these distant galaxies through targeted follow-up and serendipitous detections/blind line scans. Finally, with its leap in sensitivity compared to previous (sub-)millimetre arrays, it has enabled the detection of these powerful dust/gas tracers much further down the luminosity function through both statistical studies of colour/mass-selected galaxy populations and dedicated deep fields. We review the main advances ALMA has helped bring about in our understanding of the dust and gas properties of high-redshift ( ) star-forming galaxies during these first 9 years of its science operations, and we highlight the interesting questions that may be answered by ALMA in the years to come.
阿塔卡马大型毫米波/亚毫米波阵列（ALMA）目前正在改变我们对遥远宇宙中恒星形成星系的看法。在ALMA出现之前，我们对遥远星系中被尘埃遮蔽的恒星形成的了解大多局限于最亮的亚毫米波源——即所谓的亚毫米波星系（SMG），而且即使是关于这些源的信息也很稀少，对被遮蔽的恒星形成和气体储层的分辨（即亚星系尺度）观测通常仅限于最极端和/或强引力透镜源。从2011年早期科学观测开始，过去9年的ALMA观测开启了高红移恒星形成研究的新纪元。凭借其长基线，ALMA能够以与当前最好的光学望远镜相当甚至远超其的角分辨率观测遥远的被尘埃遮蔽的恒星形成。凭借其带宽和频率覆盖范围，通过有针对性的后续观测和偶然探测/盲线扫描，它以前所未有的视角观察了这些遥远星系中相关的分子和原子气体。最后，与之前的（亚）毫米波阵列相比，其灵敏度有了飞跃，通过对颜色/质量选择的星系群体的统计研究和专门的深场观测，它能够在光度函数中更低的位置探测到这些强大的尘埃/气体示踪剂。我们回顾了在ALMA科学运行的最初9年里，它在帮助我们理解高红移恒星形成星系的尘埃和气体特性方面取得的主要进展，并强调了未来几年ALMA可能回答的有趣问题。
