The Purest Dark Matter Halos and the Processes of Galaxy Evolution

星系包含气体、恒星和暗物质的混合物。气体和恒星会发光，这使得它们很容易被研究。但是暗物质是暗的：它不发光；所以，很难学习。星系形成理论试图解释各种类型星系中气体、恒星和暗物质的混合。最近，一种新型星系被发现，即所谓的超漫射星系（udg）。这些星系包含暗物质，但似乎没有其他成分。这使得udg成为测试星系形成理论的绝佳场所。udg还可以提供关于暗物质本质的线索。寻找更多udg的竞赛已经开始，该团队有一个雄心勃勃的计划来赢得这场竞赛。他们将分析正在进行的覆盖大片天空的光学波长的调查。该团队将筛选数据以找到udg。然后，他们将研究udg的性质。高级团队成员将培训初级团队成员。该团队将与亚利桑那州的莱蒙山科学中心合作。在那里，该团队将为初中和高中教师举办一个研讨会，并邀请教师和学生参观天文台。该小组的研究成果将在研讨会上发表。该团队将使用深入的、公开的成像调查来(1)生成一个udg的目录，(2)确定所有环境下udg的整体特性，(3)将udg与正常星系进行对比，(4)测量udg的暗物质晕的轮廓。

A galaxy contains a mixture of gas, stars and dark matter. The gas and stars emit light, making them easy to study. But the dark matter is, well, dark: It does not emit light; so, it is difficult to study. Theories of galaxy formation try to account for the mixtures of gas, stars and dark matter in galaxies of all types. Recently, a new type of galaxy was discovered, the so-called ultra-diffuse galaxies (UDGs). These galaxies contain dark matter but, it seems, little else. This makes UDGs great places to test theories of galaxy formation. UDGs could also provide clues about the nature of dark matter. The race is on to find more UDGs, and the team has an ambitious plan to win the race. They will analyze ongoing surveys that cover huge swaths of the sky at optical wavelengths. The team will sift through the data to find UDGs. Then, they will study the properties of the UDGs. Senior team members will train junior team members. The team will partner with the Mount Lemmon Science Center in Arizona. There, the team will run a workshop for middle and high school teachers, plus host observatory visits by teachers and their students. The team's research will be featured in the workshop.The team will use deep, publicly-available imaging surveys to (1) produce a catalog of UDGs, (2) determine the global properties of UDGs over all environments, (3) contrast UDGs with normal galaxies, and (4) measure the profiles of the dark matter halos of UDGs.