Stars in the Milky Way thin disk formed from the settled interstellar gas with a small scale height. But their vertical motions got subsequently "heated" over time. Such vertical heating is responsible for the thickening of spiral galaxies and is prevalent throughout the cosmos, but what causes vertical heating is still an unsolved problem. Drawing on the APOGEE and Gaia data, I will present a study of the global vertical heating of the Milky Way thin disk, ranging from 3 kpc less than R_gc less than 14 kpc. I will show that gradual orbital scattering with giant molecular gas clouds could be the dominant mechanism responsible for the vertical heating of stars in the Milky Way thin disk with external perturbers such as minor mergers only playing a negligible role.

BIO
Yuan-Sen Ting is a Hubble Fellow at the Institute for Advanced Study in Princeton, jointly affiliated with Princeton University and the Carnegie Observatories. He obtained his Ph.D. in astronomy and astrophysics in 2017 from Harvard University funded through a NASA Earth and Space Science Fellowship. Before that, he completed a concurrent double degrees and masters program from the National University of Singapore and Ecole Polytechnique in France in 2012. He was awarded the Price Prize in 2016 in recognition of his work on the Milky Way which operates at the intersection of theoretical modeling, observational astronomy, machine learning, and data science.