The evolution and the interplay of the luminous and dark matter content of massive (compact) galaxies

大质量（致密）星系的发光物质和暗物质含量的演化和相互作用

• 批准号: RGPIN-2018-05425
• 负责人: Damjanov, Ivana
• 金额: $ 2.11万
• 依托单位: Saint Mary's University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2018
• 资助国家: 加拿大
• 起止时间: 2018-01-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=648597
• 关键词: evolution; interplay; luminous; dark; matter

The assembly of massive galaxies is a key test for the models of galaxy formation and evolution. At high redshift, when the Universe was a fraction of its current age, we observe massive galaxies with no signatures of active star formation that are several times smaller than their similarly massive non-star-forming counterparts in the nearby universe. Some observational and theoretical studies have suggested that ultra-compact massive systems should completely disappear as the universe ages. ******Spectroscopic measurements reveal galaxy's distance and its nature. High-resolution images show how compact galaxies really are. Using both observational facets simultaneously, I discovered a population of dense non-star-forming (i.e., quiescent) galaxies at distances when the universe was more than half of its current age. This extreme, relatively close galaxy population bridges the gap between distant and local universe and provides an insight into the transitional channels between massive compact galaxies and extended stellar systems we observe in the Milky Way's neighbourhood. The abundance of compact massive systems in mature universe presents an opportunity to study properties of extreme galaxies that are not easily accessible at larger distances and earlier cosmic times. Using massive quiescent compact galaxy samples I have shown that ultra-dense galaxies preferentially reside in dense regions of galaxy clusters, and that they span a range of galaxy ages: from systems that have just stopped forming stars to the ones that have been "red and dead" for a few billion years. ******Building on these compelling results, I will employ dense spectroscopic surveys, high-resolution large-area space- and/or ground-based imaging, and strong gravitational lensing to: 1) trace the assembly of massive compact systems, 2) explore the relations between compact and extended massive galaxies, and 3) study the interplay between compact galaxy light profiles and their dark matter halo evolution. Dense spectroscopic surveys of all galaxies (above certain brightness limit) detected in high-resolution images will provide complete galaxy samples that include both typical galaxies and the most extreme, rare objects. In addition to mapping out the temporal evolution of extreme systems, these datasets will enable the search for links between the assembly of typical galaxies and the transformations we observe in the most extreme systems. The mass distribution (luminous and dark matter) of strong lensing galaxy clusters bends the light from a distant source producing multiple images, arcs and/or rings. By reconstructing the observed shapes of lensing arcs we can map the distribution of the total mass within galaxy cluster. A sample of ultra-dense galaxies in strong lensing clusters will unveil the role that the environment of massive compact galaxies plays in sculpting their dark matter and light profiles.

大质量星系的组装是对星系形成和演化模型的关键考验。在高红移时，当宇宙只有当前年龄的一小部分时，我们观察到没有活动恒星形成迹象的大质量星系，它们比附近宇宙中类似质量的非恒星形成星系小好几倍。一些观测和理论研究表明，超紧凑的大质量系统应该随着宇宙的老化而完全消失。光谱测量揭示了星系的距离和性质。高分辨率的图像显示了星系的致密程度。同时使用这两个观测方面，我发现了一群致密的非恒星形成(即静止的)星系，它们位于宇宙年龄的一半以上的地方。这个极端的、相对接近的星系群弥合了遥远和局部宇宙之间的差距，并提供了一个洞察我们在银河系附近观察到的大质量致密星系和扩展恒星系统之间的过渡通道的机会。成熟宇宙中丰富的致密大质量系统为研究极端星系的性质提供了机会，这些星系在更远的距离和更早的宇宙时间里是不容易到达的。使用大量静止的致密星系样本，我已经证明了超高密度星系优先驻留在星系团的致密区域，它们跨越了一系列星系年龄：从刚刚停止形成恒星的系统到数十亿年来一直处于“红色和死亡”状态的系统。*在这些令人信服的结果的基础上，我将利用密集的光谱测量、高分辨率的大面积空间和/或地面成像以及强大的引力透镜来：1)追踪大质量致密系统的组装，2)探索致密和扩展的大质量星系之间的关系，以及3)研究致密星系光轮廓与其暗物质晕演化之间的相互作用。对高分辨率图像中探测到的所有星系(高于一定亮度极限)的密集光谱调查将提供完整的星系样本，其中既包括典型的星系，也包括最极端、最稀有的天体。除了绘制出极端系统的时间演化图外，这些数据集还将使我们能够搜索典型星系的组合和我们在最极端系统中观察到的变化之间的联系。强透镜状星系团的质量分布(发光物质和暗物质)会使来自远处的光线发生弯曲，从而产生多个图像、弧线和/或光环。通过重建观察到的透镜弧形，我们可以绘制出星系团内总质量的分布。一个强透镜状星系团中的超高密度星系样本将揭示大质量致密星系的环境在塑造其暗物质和光线轮廓方面所起的作用。