The Morphology of Dust-Obscured Starbursts: the e-MERLIN SuperCLASS Legacy Survey

银河系--由数千亿颗恒星组成的集合体--是我们宇宙演化的基本组成部分。 我们自己的银河系在今天的宇宙中被认为是“正常的”，延伸10万光年，并以每年1-2个新太阳的速度形成恒星。 但是，当我们看向宇宙更远的地方时，似乎遥远的过去（100亿年前）的星系是截然不同的。 每年产生100到2,000颗恒星的极端“恒星爆发”星系要典型得多，当时形成的大多数恒星都来自这种恒星爆发。 获奖团队正试图确定为什么这些星系在宇宙的历史中如此重要，为什么它们如此极端，例如它们是否是由两个较小星系的灾难性碰撞造成的，或者当宇宙更年轻时，气体（为星星形成提供动力所需的燃料）是否更密集和有效。 这些极端的恒星爆发也被尘埃严重遮蔽，使它们很难在我们眼睛可见的光学光线下看到。 来自e-MERLIN望远镜的尖端无线电波长数据将被用来穿透尘埃，并确定宇宙中最极端的恒星爆发星系的动力机制。 该项目将通过参与UT Austin的TAURUS计划来支持在天体物理学研究中代表性不足的学生的保留，本科生将在夏季的九周时间里参加一个研究项目。 获奖者将积极参与和支持像TAURUS这样的社区中代表性不足的学生。“1）来自e-MERLIN的深度（4 μ Jy）射电1.4 GHz连续谱数据，覆盖SuperCLASS领域的1.77 deg^2，获奖者将在统计学上的大样本（几个x 100）中评估高度模糊的射电星系的演化起源。 主要目的是回答以下问题：（1）尘埃星暴中的高SFR是否主要由星系相互作用驱动？ (2)来自活动星系核（AGN）的反馈在遮蔽的星暴中是否在抑制恒星形成中起作用？ 或者，在有或没有射电发光活动星系核的恒星爆发中，星星的形成没有明显的区别（活动星系核的光度依赖于什么）？ (3)星系的恒星形成表面密度告诉我们关于星星形成的强度和相对的遮蔽几何形状（与光学成像相比）的什么？ (4)通过分析星系的射电同步加速器斜率和射电形态，人们能否了解神秘的远红外/射电相关性的物理起源？ 通过对e-MERLIN SuperCLASS数据产品的直接形态学分析来解决这些问题，将对星系演化研究产生重大影响。

Galaxies -- collections of hundreds of billions of stars all bound by gravity -- are a fundamental building block in the evolution of our Universe. Our own Milky Way galaxy is regarded as 'normal' in the Universe today, stretching 100,000 light years across and forming stars at a rate of 1-2 new suns per year. But, as we look farther out into the Universe, it seems that galaxies in the distant past (10 billion years ago) were dramatically different. Extreme "starbursting" galaxies that produced 100 to 2,000 stars per year were much more typical, and most stars formed at that time came from such starbursts. The awarded team is trying to determine why these galaxies were so important in the Universe's history and why they are so extreme, for example whether or not they are caused by the catastrophic collision of two smaller galaxies, or whether the gas (the fuel needed to power star formation) was more dense and efficient when the Universe was much younger. These extreme starbursts are also heavily obscured by dust, making them hard to see in optical light visible to our eyes. Cutting edge radio-wavelength data from the e-MERLIN telescope will be used to peer through the dust and determine the powering mechanism for the Universe's most extreme starbursting galaxies. This project will support the retention of under-represented students in astrophysics research through participation in the TAURUS program at UT Austin, where undergraduate students spend nine weeks of the summer on a research project. The awardee will be proactive in engaging and supporting under-represented students in communities like TAURUS.With a unique data set of high-resolution (0."1) deep (4 uJy) radio 1.4 GHz continuum data from e-MERLIN covering 1.77 deg^2 in the SuperCLASS field, the awardees will assess the evolutionary origins of highly-obscured radio galaxies in a statistically large sample (few x 100) out to z~3. The objectives are to answer the following questions: (1) Are the high-SFRs in dusty starbursts primarily driven by galaxy interactions or not? (2) Does feedback from Active Galactic Nuclei (AGN) in obscured starbursts play a role in suppressing star-formation? Or is there no discernible difference in star formation seen in starbursts with or without radio-luminous AGN (and what is the dependence on the AGN luminosity)? (3) What do galaxies' star-formation surface densities tell us about the intensity of star formation and relative obscuration geometries (when compared to optical imaging)? (4) Can one learn about the physical origins of the mysterious far-infrared/radio correlation by analyzing galaxies' radio synchrotron slope and radio morphologies? Answering these questions through direct morphological analysis of the e-MERLIN SuperCLASS data products will have significant impact on galaxy evolution studies.