Collaborative Research: A Quantitative Framework for the Flow of Metals in Nearby Galaxies

化学元素，如氧和氮，是在恒星内部形成的。当恒星以超新星爆炸的形式结束生命时，这些元素中的许多被排出并混合到星系内的局部环境中。这些被排出的元素是未来恒星和行星的种子。如果有足够多的超新星爆炸，或者星系很小，一些元素将完全离开星系，最终进入星系间空间。因此，测量星系中元素的类型，并找到元素的位置，为了解宇宙中星系的历史提供了重要的线索。这些研究人员将对36个附近星系进行光学和无线电波长观测，以研究星系如何产生、分布和排出元素。他们的研究结果将帮助我们了解星系是如何随时间变化的，并将被用作星系形成模型的输入。从根本上说，观测到的邻近星系的气相金属丰度应该与恒星核合成产物的产生和释放相对应，因此，提供了星系形成和生命周期的可靠痕迹。整体尺度关系，如质量-金属丰度关系，表明气相金属丰度随星系质量的增加而急剧增加。研究人员试图建立一个关于低质量星系中金属的生产、运输、分布和保留的总体定量框架。具体来说，他们将从一套全面的光谱和成像数据中确定附近宇宙中低质量星系的统计样本的完整化学富集历史。两位研究人员都是女性天文学家，她们将通过与本科生和研究生合作开展这项研究项目，努力培养一支多样化的、具有全球竞争力的STEM劳动力队伍。此外，他们的研究亮点将在公共“StarDate”广播节目上播出，听众达75万人。这位联合研究员将继续领导全国范围内减少无线电波长干扰的工作。减少射电干扰的努力对于开展射电天文学研究至关重要。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Chemical elements, such as oxygen and nitrogen, are forged in the interior of stars. When stars end their lives as supernova explosions, many of these elements are expelled and mix into the local environment within a galaxy. These expelled elements are the seeds for future generations of stars and planets. If there are enough supernova explosions, or if the galaxy is small, some of the elements will leave the galaxy entirely and end up in intergalactic space. Therefore, measuring the types of elements in galaxies, and finding where the elements are located, give important clues about the history of galaxies in the Universe. These investigators will perform optical and radio wavelength observations of 36 nearby galaxies to study how galaxies produce, distribute, and expel elements. Their research results will help us understand how galaxies change over time and will be used as input to galaxy formation models. Fundamentally, the observed gas-phase metallicities in nearby galaxies should correspond to the production and release of stellar nucleosynthesis products and, thus, provide a robust trace of galaxy formation and life cycle. Global scaling relations, such as the mass-metallicity relation, show gas-phase metallicities increase steeply with galaxy mass. The investigators seek to build an over-arching, quantitative framework of the production, transport, distribution, and retention of metals in low-mass galaxies. Specifically, they will determine the full chemical enrichment histories of a statistical sample of low-mass galaxies in the nearby universe from a comprehensive set of spectroscopic and imaging data.The investigators, both women astronomers, will work to develop a diverse, globally competitive STEM workforce by working with undergraduate and graduate students on this research project. Additionally, their research highlights will be broadcasted on the public "StarDate" Radio program to an audience of 750,000. The co-investigator will continue to lead nationwide efforts to reduce interference at radio wavelengths. The efforts to reduce radio interference are critical for enabling radio astronomy research.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.