Illuminating Galaxy Formation with the Atacama Cosmology Telescope

星系外天体物理学和宇宙学的一个中心目标是找到以下问题的答案：星系如何影响它们的环境？是什么过程导致星系中恒星的形成停止？为了回答这些问题，这项研究将使用一种新技术来探测在美国国家科学基金会资助的先进阿塔卡马宇宙望远镜调查和暗能量调查中发现的星系内部和周围的电离气体分布，从而比目前的知识提高近两个数量级。这将为西蒙斯天文台和美国国家科学基金会资助的维拉鲁宾天文台进一步显著提高灵敏度奠定基础，这两个天文台都将在本世纪20年代初上线。作为这项调查的一部分，PI将指导一名来自哥伦比亚大学桥梁项目的学生，这是一个为期两年的学士学位后项目，旨在提高来自代表性不足群体的学生在STEM博士项目中的参与度，以及一名通过西蒙斯- nsbp学者项目（西蒙斯天文台和全国黑人物理学家协会之间的合作伙伴关系）的暑期本科生。在过去的十年中，经过几次3到4西格玛的探测，由于美国国家科学基金会资助的先进阿塔卡马宇宙望远镜（ACT）的调查及其与大型星系调查的重叠，特别是暗能量调查（DES），对运动Sunyaev-Zel 'dovich （kSZ）信号的测量现在将大大提高精度。该项目将开发“投影场”kSZ估计器，以PI最近首次使用该工具进行检测为基础。关键的是，与其他kSZ估计方法不同，这种方法不需要对每个星系进行光谱红移。将该估计器应用于ACT和DES的数据来测量投影场ksz星系的相互关系，使用这些调查中已经到手的数据，将得到这个量的~60西格玛测量值。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

A central goal of extragalactic astrophysics and cosmology is to find answers to questions like: How do galaxies affect their environments? What processes are responsible for shutting off star formation in galaxies? To answer these questions, this research will use a new technique to probe the ionized gas distribution in and around galaxies identified in the NSF-funded Advanced Atacama Cosmology Telescope survey and the Dark Energy Survey, resulting in an improvement of nearly two orders of magnitude over current knowledge. This will set the stage for a further significant increase in sensitivity to follow from the Simons Observatory and the NSF-funded Vera Rubin Observatory, both coming online in the early 2020s. As part of this investigation, the PI will mentor a student from the Columbia University Bridge Program, a two-year post-baccalaureate program that increases the participation of students from under-represented groups in STEM Ph.D. programs, and a summer undergraduate student through the Simons-NSBP Scholars Program, a partnership between the Simons Observatory and the National Society of Black Physicists.After several 3 to 4-sigma detections in the past decade, measurements of the kinematic Sunyaev-Zel’dovich (kSZ) signal are now set to dramatically improve in precision as a result of the NSF-funded Advanced Atacama Cosmology Telescope (ACT) survey and its overlap with large-scale galaxy surveys, particularly the Dark Energy Survey (DES). This project will develop the “projected-field” kSZ estimator, building on the PI’s recent first detection using this tool. Crucially, unlike other kSZ estimators, this approach does not require a spectroscopic redshift for each galaxy. Application of this estimator to data from ACT and DES to measure the projected-field kSZ-galaxy cross-correlation will result in ~60-sigma measurements of this quantity using data already in hand from these surveys.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.