U.S.- South Africa Collaboration: Catalyzing a Deep Neutral Hydrogen Survey with MeerKAT

了解星系如何在宇宙时间内形成和演化是现代天体物理学的核心挑战之一。 在过去的15年里，天文学家通过研究星系中恒星的性质，对早期宇宙中遥远星系的情况有了大量的了解;然而，人们对它们的气体性质知之甚少，特别是相对冷和扩散的材料，其中氢是原子（而不是离子或分子）该项目将通过催化一项新的国际合作，朝着理解宇宙中性原子氢迈出重要的第一步，该合作已被批准进行5000-在南非建造的射电望远镜阵列上进行了一个小时的调查。 新的阵列被称为MeerKAT，新的调查采用了“用MeerKAT阵列看遥远的宇宙”或LADUMA的名称。 美国国家科学基金会的资助将使12名美国科学家能够参加2011年底或2012年初在南非开普敦举行的LADUMA调查的首届“全体”合作会议。 当地的主持人将是开普敦大学的Sarah Blyth博士，他与欧洲航天局的Benne Holwerda博士和罗格斯大学、新泽西的州立大学的Andrew Baker博士共同领导LADUMA。美国代表团将以学生参与为特色，包括罗格斯大学、国家射电天文台、亚利桑那大学、加州大学伯克利分校的代表，科罗拉多大学、新墨西哥州大学、北卡罗来纳州大学、威斯康星州大学和西弗吉尼亚大学。这个项目的智力价值主要来自于一项调查的巨大科学潜力，这项调查最终将能够在宇宙还不到现在年龄的一半的时候探测到中性原子气体。 该合作的第一次“全体”会议将汇集来自56人团队的无线电，光学和理论天文学家，以确定调查的最佳策略，并为关键领域的集中准备工作奠定基础，例如与其他望远镜获取补充数据和建立学生的联合监督。 由于开普敦是MeerKAT工程办公室的所在地，会议还将允许LADUMA科学家和MeerKAT工程师进行面对面的讨论。LADUMA合作的更广泛影响包括有机会让美国科学家和学生参与新的国际研究合作。 LADUMA团队的所有美国成员都有很好的监督学生的记录，并且都有任命，这将有助于将来招募学生参加调查。 美国LADUMA团队中有一半与南部非洲光学大望远镜（SALT）合作伙伴关系的一部分机构有联系，加强了这些机构与南非之间已经存在的联系，并促进了合作者之间的新关系。 这种伙伴关系还将为南苏丹的教育和推广提供机会。该奖项由NSF国际科学与工程办公室资助。

Understanding how galaxies form and evolve across cosmic time is one of the central challenges of modern astrophysics. In the last fifteen years, astronomers have learned a great deal about distant galaxies in the early universe by studying the properties of their stars; however, much less is known about the properties of their gas, especially the relatively cool and diffuse material in which hydrogen is atomic (rather than ionized or molecular) in form.This project will take an important first step toward understanding the universe's neutral atomic hydrogen by catalyzing a new international collaboration that has been approved to conduct a 5000-hour survey with an array of radio telescopes being built in South Africa. The new array is known as MeerKAT, and the new survey has adopted the name "Looking At the Distant Universe with the MeerKAT Array" or LADUMA. NSF funding will allow 12 U.S. scientists to attend the LADUMA survey's inaugural "all hands" collaboration meeting in Cape Town, South Africa in late 2011 or early 2012. The local host will be Dr. Sarah Blyth of the University of Cape Town, who shares leadership duties for LADUMA with Dr. Benne Holwerda of the European Space Agency and Dr. Andrew Baker of Rutgers, the State University of New Jersey.The U.S. delegation will feature student participation and include representation from Rutgers, the National Radio Astronomy Observatory, the University of Arizona, the University of California at Berkeley, the University of Colorado, the University of New Mexico, the University of North Carolina, the University of Wisconsin, and West Virginia University.The intellectual merit of this project derives principally from the immense scientific potential of a survey that will ultimately be able to detect neutral atomic gas at an epoch when the universe was less than half its present age. The collaboration's first "all hands" meeting will bring together radio, optical, and theoretical astronomers from across the 56-person team to determine the optimal strategy for the survey and to lay the groundwork for focused preparatory efforts in key areas, such as the acquisition of complementary data with other telescopes and the establishment of joint supervision of students. Because Cape Town is the location of the MeerKAT engineering office, the meeting will also allow face-to-face discussions between LADUMA scientists and MeerKAT engineers.The broader impacts of the LADUMA collaboration include an opportunity to engage U.S. scientists and students in a new international research collaboration. All U.S. members of the LADUMA team have strong records of supervising students, and all have appointments that will facilitate recruitment of students to the survey in the future. Half of the U.S. LADUMA team have affiliations with institutions that are part of the optical Southern African Large Telescope (SALT) partnership, strengthening the bonds that already exist between these institutions and South Africa and catalyzing new relationships among the collaborators. The partnership will also result in opportunities for education and outreach in S. Africa.This award is being funded by NSF's Office of International Science and Engineering.