Cold Gas in Hot Galaxies

星系究竟是如何形成和发展的，这是一个长期困扰天文学家的谜。因此，对科学家来说，解开星系形成和发展的线索至关重要。该项目追求三个主要目标来推动这一领域的发展。第一个目标是通过研究早期类型（椭圆和透镜状）星系的冷气体的详细特性来解读它们的聚集、相互作用和吸积历史。第二个目标是测试星际介质结构的经验和理论模型及其对恒星形成效率的影响。具体来说，对星际介质理论模型的真正考验将是，为晚期螺旋星系建立的模型是否可以推广到椭圆星系和透镜星系内部非常不同的条件。第三个目标是探索活动星系核（AGN）驱动的反馈在清除星系中的冷气体中所起作用的观测约束，从而改变它们的形态和颜色，并有助于建立今天的哈勃序列。为了实现这三个目标，研究人员将利用对邻近早期星系的体积有限、研究充分的ATLAS-3D样本的观察。现有的毫米干涉仪和国家射电天文台（NRAO）的扩展甚大阵列（EVLA）将绘制痕量分子物种，作为冷ISM性质的天体化学探测器，并将对低水平恒星形成活动和低水平AGN活动的射电连续辐射进行深入观测。天体化学工作也将适用于早期的阿塔卡马大毫米/亚毫米阵列（ALMA）科学建议。在教育方面，该项目将支持两名研究生研究助理和一名本科生研究员，为期三年。该项目还将通过开发与该研究项目相关的射电天文学课程，为K-12教师提供科学培训，该课程将在新墨西哥理工大学为K-12教师提供的科学教学硕士课程中授课。受益于该项目的教师将教授代表性不足的学生，从而加强他们对STEM职业的接触和培训。为K-12教师提供的研究和培训是使用射电望远镜。教师们不仅要学习如何像研究项目那样收集和检查射电望远镜数据，还要学习新墨西哥州专业射电望远镜的功能，这是一个集研究和教育于一体的巨大而难得的教师培训机会。

Exactly how galaxies form and develop is a mystery that has long eluded astronomers. So, it is crucial for scientists to unravel clues of galaxy formation and development. This project pursues three primary goals to move this field forward. The first goal is to read the assembly, interaction, and accretion history of early-type (elliptical and lenticular) galaxies through studies of the detailed properties of their cold gas. The second goal is to test empirical and theoretical models of the structure of the interstellar medium and its effect on star formation efficiency. Specifically, the true test of theoretical models of the interstellar medium will be whether the models developed for late-type spirals can be extended to the very different conditions inside elliptical and lenticular galaxies. The third goal is to pursue observational constraints on the role of active galactic nuclei (AGN)-driven feedback in clearing cold gas from galaxies, thus transforming their morphology and color and contributing to the establishment of today's Hubble sequence.To accomplish these three goals, the investigators will use the observations of the volume-limited, well-studied ATLAS-3D sample of nearby early-type galaxies. Existing millimeter interferometers and the National Radio Astronomy Observatory's (NRAO's) Expanded Very Large Array (EVLA) will map trace molecular species as astrochemical probes of the properties of the cold ISM, and will make deep observations of radio continuum emission from low level star formation activity and low level AGN activity. The astrochemical work will also be suitable for early Atacama Large Millimeter/submillimeter Array (ALMA) science proposals.Educationally, the project will support two graduate student research assistants for three years as well as an undergraduate researcher. The project will also provide K-12 teacher training in science through the development of a radio astronomy course, related to the research project, delivered in a Master of Science Teaching program offered at New Mexico Tech for K-12 teachers. The teachers who benefit from this program will be teaching underrepresented students and thereby strengthening their exposure in and training for STEM careers. The research and training offered to K-12 teachers is hands-on using a radio telescope. The teachers learn not only how to collect and examine radio telescope data like the research project, but they also learn how the professional radio telescopes in New Mexico function, a tremendous and rare teacher training opportunity that integrates research and education.