Mapping the Chemical Evolution of Disk Galaxies with MaNGA

星系的化学成分--每个星系中氢、氦、氧、氮、铁等的相对含量--为这些星系是如何演化的提供了重要线索。然而，当星系样本很小时，星系演化的已知驱动力--获得可以形成恒星的气体、形成恒星的类型及其在星系中形成的位置、以及动力学过程，如通过超新星爆炸在星系内外的气体重新分配等--很难分离出来，而且样本中的所有星系都非常相似。这项计划计划开发所需的计算机代码，以观察数千个具有非常不同性质的星系的样本，以便深入了解它们的化学成分与星系演化的驱动因素之间的关系。解释天文学家如何能够通过观察不同波长的光(它们的电磁光谱)来收集和使用关于恒星和气体的信息是具有挑战性的。然而，这些光谱是我们对宇宙中恒星、行星、星云、星系和大尺度结构的质量、运动、温度和组成的大多数测量的根源。许多难懂的概念，如月亮的相，可以通过演示有效地教授。PI将与一名本科生合作，设计和制造一种便携式光谱仪--天文学家用来研究不同波长光的便携式仪器--用于教室和公共户外。这项提议将开发和发布一个复杂的代码，以测量漫画中的星云丰度梯度。这将使研究盘状星系中的星云丰度梯度成为可能，这将为驱动星系演化的过程提供一个独特而强大的探测器：气体吸积、恒星形成和气体外流。即使在我们自己的银河系中，这些过程的复杂相互作用也很难解开。然而，通过研究处于各种演化状态的星系，可以获得对这些过程的洞察。这一代码的开发是能够分析漫画数据集信息的关键一步。

The chemical composition of galaxies - the relative amounts each galaxy has of hydrogen, helium, oxgen, nitrogen, iron, etc. - provides important clues to how those galaxies have evolved. However, the known drivers of galaxy evolution - acquiring gas that can form stars, the types of stars that form and where they form in the galaxy, and dynamical processes, such as the reistribution of gas within and outside galaxies through supernova explosions, etc. - are difficult to separate when the sample of galaxies is small, and all the galaxies in the sample are very similar. This proposal plans to develop the computer codes needed look at a sample of several thousand galaxies with very different properties in in order to provide insight into how their chemical compositions are related to the drivers of galaxy evolution.Explaining how astronomers are able to gather and use information about stars and gas by looking at the different wavelengths of light (their electromagnetic spectrum) is challenging. Yet these spectra lie at the root of most of our measurements of the masses, motions, temperatures, and compositions of stars, planets, nebulae, galaxies, and large scale structure in the Universe. Many difficult concepts, such as the phases of the moon, can be effectively taught with the aid of demonstrations. The PI will work with an undergraduate student to design and build a portable spectrograph - a portable version of an instrument that astronomers use to study the different wavelengths of light - to be used in classrooms and for public outreach.This proposal will develop and publish a sophisticated code to measure nebular abundance gradients in MaNGA. This will enable the study of nebular abundance gradients in disk galaxies, which offer a uniquely powerful probe of the processes that drive galaxy evolution: gas accretion, star formation, and gas outflows. The complex interplay of these processes is challenging to disentangle even in our own Milky Way. However, insights into these processes can be gained by examining galaxies in a wide variety of evolutionary states. The development of this code is a key step in being able to analyze the information from the MaNGA dataset.