The Road to the Virgo Cluster: The DECam/IRAC Galaxy Environment Survey

这是一个推进我们对各种过程的理解的建议，这些过程负责观察到的星系特性，以及这些特性如何随着星系环境而变化，例如，邻居很少的星系与拥挤在一起的星系。这对于帮助科学家区分有助于星系成长的属性的相对重要性是很重要的，包括上面提到的环境，星系中形成的恒星的数量和类型，以及星系中的可见物质如何与与之相关的暗物质相互作用。提议者将对星系及其环境进行大规模调查，这些星系的距离与宇宙年轻时相对应，但足够成熟，可以形成星系团，有些星系几乎形成了所有的恒星。在这个时期观察星系是很重要的，因为这是预计环境影响会很强的时期。PI建议发展和实施一些公众宣传和课程活动，由他和受资助的博士后共同开展。PI所在的机构中有大量未被充分代表的少数民族。将项目数据整合到天文学学生实验室的提议是将研究带入课堂的一个很好的例子，它为博士后提供了一个获得教育和推广经验的机会。PI还计划每月向高中生进行公开讲座。该提案描述了对z=0.8-1.5的星系环境的首次系统调查。此次调查将结合0.3-1微米的深度光学成像和3-5微米的深度近红外成像，覆盖面积是COSMOS调查的15倍以上。通过这种方式，新的巡天将打开红移z=0.8-1.5的宇宙，就像斯隆数字巡天打开了z=0.1的本地宇宙一样。该团队将测量星系恒星质量/光晕质量之间的关系及其对环境的依赖，并解决以下问题。星系标度定律何时出现，它们如何依赖于环境？将星系转化为具有低质量比恒星形成率的红序星系的物理机制是什么？这些机制如何取决于星系质量、环境和红移？

This is a proposal to move forward our understanding of the variety of processes that are responsible for observed galaxy properties, and how these vary with galaxy environment, e.g. galaxies that have few neighbors versus galaxies that are crowded closely together. This is important to help scientists to distinguish the relative importance of properties that contribute to the growth of galaxies, including environment as mentioned above, the amount and type of stars being formed in galaxies, and how the visible matter in galaxies interacts with the dark matter associated with them. The proposers will do a large survey of galaxies and their environments at distances that correspond to when the Universe was young, but mature enough that clusters of galaxies had formed and some galaxies had formed nearly all their stars. It is important to look at galaxies at this epoch, as that is when it is expected that environmental effects are strong.The PI proposes the development and implementation of several public outreach and curricular activities, to be carried out both by him and the supported postdoc. The PI is at an institution which has a significant population of under-represented minorities. The proposed integration of the project data into a lab for astronomy students is a great example of bringing research into the classroom, and it provides an opportunity for the postdoc to acquire experience in education and outreach. The PI also plans monthly public lectures for high school students.The proposal describes the first systematic survey of galaxy environment at z=0.8-1.5. The survey will combine deep optical imaging from 0.3-1 micron with deep near-IR imaging from 3-5 micron over an area more than 15 times that of the COSMOS survey. In this way, the new survey will open the redshift z=0.8-1.5 universe in a way that the Sloan Digital Sky Survey has opened the local universe at z=0.1. The team will measure the relation between galaxy stellar masses/halo masses and its dependence on environment and address the following questions. When do galaxy scaling laws appear and how do these depend on environment? What are the physical mechanisms that transform galaxies to red sequence galaxies with low mass-specific star-formation rates? How do these mechanisms depend on galaxy mass, environment, and redshift?