Title: Spiral arms as a tool to probe galaxy evolution

Speaker: 余思悦

Institute: Department of Astronomy, Peking University

Host: Haoran Yu

Time: 14:30-16:30, Thursday, April 8

Location: Physics Building 552

Abstract:

Spiral arms are the most generic structures in disk galaxies. Their physical origin and connection to galaxy evolution are, however, debated. The literature studies are usually based on visual classifications and thus are subjective and inefficient. To reveal the nature of spirals, I developed quantitative methods to characterize spiral arms, with the measurement limit is understood using image simulations. I found that the spiral properties correlate with global galaxy properties such as stellar mass, morphology, rotation curve, and color index, providing clues to spiral arms origin. Spiral arms of young stars exhibit tighter pitch angle than that of old stars, suggesting spiral arms are long-lived patterns. I will present evidence for supporting spiral arms playing an important contributing role in setting star formation rate in disk galaxies. Spiral arms exist not only in galaxies, but also in protoplanetary disks. I will at the end introduce my work investigating density waves as the formation mechanism of the spiral arms in protoplanetary disks

Bio:

2014年获厦门大学物理学学士学位，2014-2020年在北京大学天文系就读博士，2020年7月获得博士学位。主要研究兴趣为（1）星系形态的量化分析和起源；（2）旋臂结构的形成与演化；（3）河外星系的恒星形成；（4）数值模拟中的星系形态；（5）原行星盘的旋臂的起源。截止2021年3月，已在ApJ国际著名学术期刊上发表6篇一作或者通讯文章（另有1篇正在审稿），以及2篇合作文章。

Ref:

https://ui.adsabs.harvard.edu/abs/2018ApJ...862...13Y/abstract

https://ui.adsabs.harvard.edu/abs/2018ApJ...869...29Y/abstract

https://ui.adsabs.harvard.edu/abs/2019ApJ...871..194Y/abstract

https://ui.adsabs.harvard.edu/abs/2019ApJ...877..100Y/abstract

https://ui.adsabs.harvard.edu/abs/2020ApJ...900..150Y/abstract

https://ui.adsabs.harvard.edu/abs/2021ApJ...906...19C/abstract