Collaborative Research: RUI: Tracing Galaxy Quenching in the Cosmic Web With Spatially-Resolved Star-Formation Maps

密集星系团中的星系与这些区域以外的星系明显不同（即，在“领域”）甚至在星系的真正性质被认识之前就被认识到了。这一观察的基础是，星系的气体供应和星星形成活动也显示出对环境的显著依赖。这个项目的目标是更好地了解当星系穿过宇宙网到达星系团中心时，两者是如何改变的。该团队将通过测量14，000个附近星系的恒星形成和恒星盘的相对程度来量化星星形成的环境“淬火”-比以前的研究增加了20倍-以解开环境，星系质量和形态的相关影响。该奖项还将涉及在研究两个机构的本科生，并支持外展工作，以区域K-12学生以及暑期教师培训计划。这项工作将（1）限制已知发生气体剥离的致密环境的猝灭时间尺度，（2）确定星系团周围的宇宙细丝网络如何改变星系内星星形成的空间分布，（3）阐明这些过程如何在不同环境中作用以产生所观察到的变化，以及（4）产生具有持久遗产价值的数据集，用于研究邻近宇宙中的星系演化。研究小组将用Sersic模型拟合样本星系，并确定恒星的有效半径（来自DESI遗产巡天的光学grz和来自WISE的红外3.4 um）和星星形成（WISE 12 um）。非参数配置文件和总流量也将通过椭圆孔径测光使用紫外（GALEX），光学grz和红外（WISE）图像得出这些星系。这些互补的技术将产生强大的星系样本的结构参数。将使用该小组为克服与测量大型星系光度学有关的挑战而设计的定制软件，并将通过分析整个样品的紫外到红外光谱能量分布来估计其自洽的恒星质量和恒星形成率。该团队将通过考虑细丝以及集群和场成员来采用更复杂的星系环境表征。这是一个重要的补充，因为最近的流体动力学模拟表明，细丝可能是星系转变的重要场所。这个奖项反映了NSF的法定使命，并已被认为是值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估的支持。

That galaxies in dense clusters appear markedly different from galaxies outside these regions (i.e., in the "field") was recognized even before the true nature of galaxies was recognized. Underlying this observation is the fact that a galaxy’s gas supply and star formation activity also show a marked dependence on environment. The objective of this project is to better understand how both are altered as a galaxy moves through the cosmic web to the cluster centers. The team will quantify environmental "quenching" of star formation by measuring the relative extent of the star-forming and stellar disks for 14,000 nearby galaxies - a factor of 20 increase over previous studies - to disentangle the correlated effects of environment, galaxy mass, and morphology. This award will also involve undergraduate students at both institutions in research, and support outreach efforts to area K-12 students as well as a summer teacher training program. This work will (1) constrain the quenching timescale for the densest environments where gas stripping is known to occur, (2) determine how the network of cosmic filaments around clusters alters the spatial distribution of star formation within galaxies, (3) shed light on how these processes act in different environments to produce the observed changes, and (4) produce a data set with lasting legacy value for studies of galaxy evolution in the nearby universe. The team will fit Sersic models to the sample galaxies and determine the effective radii of the stars (optical grz from the DESI Legacy Surveys and infrared 3.4um from WISE) and star formation (WISE 12um). Non-parametric profiles and total fluxes will also be derived for these galaxies through elliptical aperture photometry using ultraviolet (GALEX), optical grz, and infrared (WISE) images. These complementary techniques will yield robust structural parameters for to galaxy sample. Custom software designed by the team to overcome the challenges associated with measuring photometry of large galaxies will be used, and self-consistent stellar mass and star-formation rates (SFR) will be estimated for the entire sample through the analysis of their ultraviolet through infrared spectral energy distributions. The team will adopt a more sophisticated characterization of galaxy environment by considering filaments as well as cluster and field membership. This is an important addition as recent hydrodynamic simulations suggest that filaments may be important sites of galaxy transformation.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.