Gas and star formation in the extreme environments of starburst galaxies

星暴星系极端环境中的气体和恒星形成

基本信息

批准号：
RGPIN-2019-05395
负责人：
Wilson, Christine
金额：
$ 3.64万
依托单位：
McMaster University
依托单位国家：
加拿大
项目类别：
Discovery Grants Program - Individual
财政年份：
2019
资助国家：
加拿大
起止时间：
2019-01-01 至 2020-12-31
项目状态：
已结题

来源：
https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=689952
关键词：
Gas star formation extreme environments

项目摘要

In the universe around us, galaxies are made up of billions of stars, many with planets circling around them. This means that we must first understand how stars form before we can understand the formation of either galaxies or planets. My research program focuses on nearby galaxies that are currently experiencing an intense burst of star formation, turning gas into stars at rates that are 10-100 times faster than the rate in galaxies like our own Milky Way. Specifically, I study the physical properties of the gas that is the fuel for star formation, in order to understand why the star formation in these galaxies has kicked into overdrive. ******Although these “starburst galaxies” are now relatively rare, these high rates of star formation were normal in the early universe, when young galaxies rich in gas were forming most of the stars we see today. However, because these young galaxies lie at incredibly large distances, even the most powerful telescopes find it extremely difficult to measure the detailed properties that are needed for comparison with simulations of star and galaxy formation. Nearby starburst galaxies provide the opportunity to probe the extreme environments (high densities of gas and star formation) that were common in the early universe, but now on the scales of a few hundred light years that are required to provide strong tests of star formation models.******My research team will use data from a powerful radio telescope, the Atacama Large Millimeter/submillimeter Array (ALMA), to attack the problem of star formation in extreme environments along several fronts. (1) We will compare rates of star formation with the amount of available gas to probe the universality of the physics that underpins the empirical “star formation law” that has been established for galaxies like our own Milky Way. (2) We will make the first detailed measurements of the populations of individual giant gas clouds in starburst galaxies. Changes in cloud properties may explain the intense star formation: for example, higher density clouds will collapse faster, which could drive the gas to form stars more rapidly. (3) We will also use these new cloud catalogs to obtain critical calibrations that are needed to turn our radio images of galaxies into accurate measurements of the mass of gas in those galaxies. (4) In the most extreme starburst galaxies in the local universe, galaxies so rich in gas and dust that their centres are completely hidden from view in visible light, we will use rarer molecular isotopes (such as 12C18O instead of 12C16O) to probe how long the starbursts last and what kinds of stars they form. ******Overall, this program of research will provide a breakthrough in our understanding of star formation in the most extreme environments in the universe today and will have strong impact on our understanding of the main epoch of galaxy formation in early universe.

在我们周围的宇宙中，星系由数十亿颗恒星组成，许多星星周围盘旋。这意味着我们必须首先了解恒星如何形成，然后才能理解星系或行星的形成。我的研究计划的重点是近乎星系，这些星系目前正经历着强烈的恒星形成，将气体变成恒星的速度比我们自己的银河系等星系的速度快10-100倍。具体而言，我研究气体的物理特性，这是恒星形成的燃料，以了解为什么这些星系中的恒星形成已经开始过度。 ****尽管这些“ Starburst星系”现在相对较少，但这些高恒星形成率在早期的宇宙中是正常的，当时富含气体的年轻星系正在形成我们今天看到的大多数恒星。但是，由于这些年轻的星系位于极为较大的距离上，即使是最强大的望远镜，也很难测量与恒星和星系形成的模拟所需的详细特性。附近的Starburst星系提供了机会，可以探测早期宇宙中常见的极端环境（高密度和恒星形成），但现在在几百年的尺度上，需要提供恒星形成模型的强大测试。正面。（1）我们将将恒星形成率与可用气体的量进行比较，以探究为基于我们自己的银河系等星系建立的经验“恒星形成法”的物理学的宇宙。（2）我们将对Starburst星系中单个巨型云的种群进行首次详细测量。云特性的变化可能解释了强烈的恒星形成：例如，较高的密度云将更快地塌陷，这可能会驱动气体更快地形成恒星。（3）我们还将使用这些新的云目录来获得关键的校准，这些校准需要将我们的星系的无线电图像转变为对这些星系中气体质量的准确测量。（4）在当地宇宙中最极端的星球星系中，星系富含气体和灰尘，以至于它们的中心完全可以在可见光的光线下完全隐藏，我们将使用较稀有的分子同位素（例如12c18o而不是12c16o）来探测它们形成的恒星持续和什么恒星。 *****总的来说，这项研究计划将在当今宇宙中最极端环境中对恒星形成的理解为我们的理解提供突破，并将对我们对早期宇宙中星系主要形成的主要时代的理解产生强烈的影响。