Stellar Populations in Spiral Galaxies

螺旋星系中的恒星种群

• 批准号: RGPIN-2015-06115
• 负责人: Robert, Carmelle
• 金额: $ 1.6万
• 依托单位: Université Laval
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2016
• 资助国家: 加拿大
• 起止时间: 2016-01-01 至 2017-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=613952
• 关键词: Stellar; Populations; Spiral; Galaxies

STELLAR POPULATIONS IN SPIRAL GALAXIES The evolution of galaxies is an exciting subject, mainly because or our increasing capabilities to build powerful instruments to look at large distances when galaxies were much younger, but also because we understand more about their content. Nevertheless, the assemblage and evolution of galaxy components is still not well understood. Stellar populations are good tracers of the change experienced by a galaxy over time. It is therefore proposed here to use them to gain insights into the different mechanisms that drive star formation and galaxy evolution. This research program will include SpIOMM and SITELLE, new state of the art astronomical instruments at the Observatoire du Mont-Mégantic and Canada-France-Hawaii Telescope, to obtain simultaneously spectra in the visible for every region on the whole surface of a nearby galaxy with a high spatial resolution. Emission and absorption lines seen in these datacubes will be analysed using evolutionary stellar population synthesis models and radiative transfer codes to characterize the age, chemical composition, and mass of the galaxy components. A technique to separate the signatures of the different populations that overlap in a spectrum is to be refined. A special attention is to be given to the diffused ionized gas that is contaminating the component spectral indicators. The origin of this gas is not well established yet, but becomes easier to study now with these new instruments. Young starburst regions will also be analyzed using the ultraviolet flux produced by their numerous OB stars with data from the Ultraviolet Imaging Telescope (to be launched in 2015). UVIT will be extremely useful to compare the starburst ultraviolet properties and morphology with the visible ground-based data from SpIOMM and SITELLE. The high spatial resolution offered by all these instruments will be unique to establish links between the different component properties, for example to measure chemical abundance gradients through the galactic disks. SITELLE and UVIT surveys are being designed which include nearby spiral galaxies with different properties (bar, interactions, mass) in order to understand the different mechanisms that are influencing star formation and galaxy evolution. This program is preparing the tools and setting the orientation for the study of galaxies at larger distances with the new generation of large telescopes to come.

旋涡星系中的恒星星族 星系的演化是一个令人兴奋的主题，主要是因为我们越来越有能力建造强大的仪器，以便在星系年轻得多的时候观察大距离，而且还因为我们对它们的内容有了更多的了解。然而，星系成分的组合和演化仍然没有得到很好的理解。恒星的数量是一个星系随时间变化的很好的示踪剂。因此，建议在这里使用它们来深入了解驱动星星形成和星系演化的不同机制。该研究计划将包括SpIOMM和SITELLE，这是梅干蒂克山天文台和加拿大-法国-夏威夷望远镜的最先进的天文仪器，以同时获得附近星系整个表面每个区域的可见光谱。具有高空间分辨率。在这些数据管中看到的发射和吸收线将使用演化恒星人口合成模型和辐射传输代码进行分析，以表征星系组成部分的年龄，化学成分和质量。将光谱中重叠的不同群体的特征分开的技术有待改进。应特别注意污染组件光谱指示器的扩散电离气体。这种气体的起源还没有很好地确定，但现在用这些新仪器更容易研究。还将利用来自紫外成像望远镜（将于2015年发射）的数据，利用众多OB星产生的紫外线通量，对年轻的星爆区进行分析。UVIT将是非常有用的比较星爆紫外线的性质和形态与可见的地面数据从SpIOMM和SITELLE。所有这些仪器提供的高空间分辨率将是建立不同成分属性之间联系的独特之处，例如测量通过星系盘的化学丰度梯度。正在设计SITELLE和UVIT巡天，其中包括附近具有不同性质（棒、相互作用、质量）的螺旋星系，以便了解影响星星形成和星系演化的不同机制。该方案正在准备工具，并确定方向，以便利用即将到来的新一代大型望远镜研究更远距离的星系。