SIGNALS and SITELLE: Massive stars and HII regions in nearby galaxies with imaging Fourier transform spectroscopy

信号和站点：通过成像傅里叶变换光谱分析附近星系中的大质量恒星和 HII 区域

• 批准号: RGPIN-2019-05840
• 负责人: Drissen, Laurent
• 金额: $ 2.04万
• 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: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=714841
• 关键词: SIGNALS; SITELLE; Massive; stars; HII

In response to CFHT's recent Call for Large Programs (2018B - 2022A semesters), an internatioal team I co-lead submitted a proposal to make use of its Imaging Fourier Transform Spectrometer SITELLE's unique capabilities to conduct a detailed survey of star-forming regions in nearby galaxies. SIGNALS, the Star formation, Ionized Gas, and Nebular Abundances Legacy Survey with SITELLE, will be based on a volume-limited sample of local extended galaxies (D 10 Mpc) that are actively forming massive stars. SIGNALS, which has been awarded 50 nights of CFHT time over the next 4 years, will provide the largest, most complete, and homogeneous database of spectroscopically and spatially resolved extragalactic HII regions ever assembled. This will enable us to study small-scale nebular physics and many other phenomena linked to massive star formation in galaxies at a mean spatial resolution of 20 pc. As is, our sample includes 39 spiral and irregular galaxies. HII regions present a wide variety of characteristics: morphology (from compact to extended shell), mass (where the low luminosity regime is not very well sampled), metallicity (where the rare metal-poor regions have been less studied), or age (following the diversity of their young stellar populations). They may be located in different galactic ecosystems and coexist with other sources of ionization (like shocks and AGN). The volume-limited sample will provide a statistically reliable laboratory, with over 50 000 resolved HII regions. By studying the spectra of spatially-resolved individual HII regions and their massive star content, SIGNALS aims at understanding how diverse local environments (nearby stellar population mass and age, gas density and chemical composition, dynamical structures, etc.) affect the star formation process. The legacy of our survey will reflect on many topics in astrophysics, from stars to very distant galaxies. Our primary immediate goals are to : 1) Quantify the impact of the near surrounding environment on the star formation process, 2) Link the feedback processes to the small-scale chemical enrichment and dynamics around star-forming regions, and 3) Measure variations of the resolved star formation rate with respect to indicators used for high-redshift galaxies. As PI of SITELLE and one of the five co-PIs of SIGNALS, I intend to devote most of my research time during the next five years to this Large Program. On the instrument side, I will play a leading role in the data reduction and quality assessment, software development and observational strategy, which will all likely evolve over the course of the survey. On the astronomical side, I will take this opportunity to come back to my main motivations behind the development of the imaging FTS technology, namely to study the influence of massive stars (and their core-collapse supernova descendants) on the kinematics and chemical enrichment of their immediate surroundings.

为了响应CFHT最近对大型项目(2018B-2022A学期)的呼吁，与我共同领导的一个国际团队提交了一份提案，利用其成像傅里叶变换光谱仪SITELLE的独特能力对附近星系的恒星形成区域进行详细调查。SITELLE的恒星形成、电离气体和星云丰度探测的信号，将基于活跃地形成大质量恒星的局部扩展星系(D 10MPC)的体积有限的样本。Signals将在未来4年内获得50晚的CFHT时间，它将提供有史以来组装的最大、最完整和最均匀的光谱和空间分辨率河外HII区域数据库。这将使我们能够研究小尺度星云物理和许多其他与星系中大质量恒星形成有关的现象，平均空间分辨率为20pC。目前，我们的样本包括39个螺旋星系和不规则星系。HII区呈现出各种各样的特征：形态(从致密壳到加长壳)、质量(低光度区没有得到很好的采样)、金属丰度(稀有金属贫区较少被研究)或年龄(遵循年轻恒星群体的多样性)。它们可能位于不同的星系生态系统中，并与其他电离源(如激波和活动星系核)共存。容量有限的样本将提供一个统计上可靠的实验室，有超过50,000个可分辨的HII区域。通过研究空间分辨的单个HII区的光谱及其质量恒星含量，Signals旨在了解不同的局部环境(附近的恒星人口质量和年龄、气体密度和化学成分、动力学结构等)是如何变化的。影响恒星的形成过程。我们调查的成果将反映天体物理学的许多主题，从恒星到非常遥远的星系。我们当前的主要目标是： 1)量化附近环境对恒星形成过程的影响， 2)将反馈过程与恒星形成区周围的小规模化学浓缩和动力学联系起来，以及 3)测量分辨恒星形成率相对于用于高红移星系的指标的变化。 作为SITELLE的PI和Signal的五个合作PI之一，我打算在接下来的五年里将我的大部分研究时间投入到这个庞大的计划中。在仪器方面，我将在数据简化和质量评估、软件开发和观测战略方面发挥领导作用，这些都可能在调查过程中发展。在天文学方面，我将借此机会回到我开发成像FTS技术背后的主要动机，即研究大质量恒星(及其核心坍塌的超新星后代)对其邻近环境的运动学和化学丰度的影响。