Collaborative Research: The Evolution of Gas in Protoplanetary Disks

拟议工作的目标是建立对原行星盘中气体行为和演化的理解。原行星盘99%的质量由气体组成。然而，天文学家甚至对气体成分的演变没有基本的了解，也不知道是什么因素推动了这种演变。 由阿尔马射电天文台收集的原行星盘观测资料将用于检验盘演化的两种主要理论。威斯康星大学麦迪逊分校的小组将设计和提供一个定期的1小时长的动手会议上的无线电波的主题为学生组游客在威斯康星大学麦迪逊分校的空间广场，当地的推广和教育中心。在亚利桑那州图森市，UA小组将与皮马县学校监督办公室合作，为K-12教师举办一个为期一天的关于无线电波的研讨会。此外，这项工作将提供研究经验，研究生，本科生，和博士后。该项目将提供一个强大的测量气体盘质量和大小在一个定义明确的样本跨越整个磁盘寿命（0.1-10百万年）的遗产库。这样的库将是至关重要的测试任何当前和未来的磁盘演化理论。该项目将通过阿尔马对原行星盘中气体演化的调查，AGE-PRO，一个公认的阿尔马第8周期大型计划（103小时，PI。Zhang）。他们将收集和分析深阿尔马观测的全面样本磁盘在整个典型的磁盘寿命。通过结合AGE-PRO观测和最先进的热化学模型，该团队将提供这些盘的精确气体质量测量（比现有限制高10-20倍），以及这些盘中气体的详细表面密度分布。然后，他们将在不同的磁盘演化机制下运行一个大型磁盘演化模型网格。通过将他们的气体分布测量结果与气盘演化模型的观测结果进行比较，他们将对气盘演化的两个主要理论：湍流粘性和磁流体动力学气盘风提供关键测试。该奖项反映了NSF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。

The objective of the proposed work is to build understanding of the behavior and evolution of gas in protoplanetary disks. Up to 99% of the mass of a protoplanetary disk consists of gas. However, astronomers do not have even a basic understanding of the evolution of the gas component or what factors drive such evolution. Observations of protoplanetary disks, collected with the ALMA radio observatory, will be used to test the two leading theories of disk evolution. The UW-Madison group will design and provide a regular 1-hour long hands-on session on the topic of radio waves for student group visitors at the UW-Madison Space Place, a local outreach and educational center. In Tucson, AZ, the UA group will develop a one day workshop for K-12 teachers on the topic of radio waves, by collaborating with the Pima County School Superintendent's Office. In addition, this work will provide research experience to graduate students, undergraduates, and a post-doc.This project will provide a legacy library of robust measurements of gas disk masses and sizes in a well-defined sample spanning over the whole disk lifetime (0.1-10 Myr). Such library will be critical to test any current and future theories of disk evolution. This project will gather breakthrough data to map the evolution of gas in protoplanetary disks, through the ALMA survey of Gas Evolution in PROtoplanetary disk, AGE-PRO, an accepted ALMA Cycle 8 large program (103 h, PI. Zhang). They will collect and analyze deep ALMA observations of a comprehensive sample of disks throughout the typical disk lifetime. By combining AGE-PRO observations and state-of- the-art thermo-chemical models, the team will provide accurate gas mass measurements of these disks (10-20 times better accuracy than existing constraints), as well as detailed surface density distributions of gas in these disks. They will then run a large grid of disk evolution models under different disk evolution mechanisms. Comparing their gas distribution measurements from observations with that of disk evolution models, they will provide critical tests to the two leading theories of disk evolution: turbulent viscosity and magneto-hydrodynamical disk winds.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.