2023 #12

Unveiling the Nature of Gas around Star-forming and Passive Galaxies

Ting-Wen Lan (National Taiwan University)

Gas around galaxies, the circumgalactic medium (CGM), plays an essential role in galaxy evolution. The CGM not only provides the gas fuel to support the star-formation activity in galaxies, but also contains the signatures of gas outflows ejected from galaxies driven by explosion of massive stars and the activity of supermassive black holes. In order to better understand how these physical mechanisms drive galaxy evolution, it is essential to observationally measure the physical properties of the CGM and explore their connection to the properties of galaxies.

This project aims to pursue this research direction by studying the physical properties of the CGM. We will utilize the spectroscopic dataset provided by the Sloan Digital Sky Survey (SDSS) and investigate the properties of metal absorption lines, induced by the intervening CGM, observed in spectra of background quasars. More specifically, we will explore the properties of metal absorption lines, such as line width and line ratio, around both star-forming and passive galaxies. The results will show novel correlations between the properties of the CGM and that of galaxies, which in turn sheds new light on the physical mechanisms driving galaxy evolution.

In this project, the student will (1) work on SDSS spectroscopic dataset, (2) develop statistical techniques, and (3) learn the astrophysics of galaxy evolution and statistics.

Required Background:
1. Basic/advanced knowledge in astrophysics is preferred, but not mandatory.
2. Basic knowledge and skills of computer programming (such as Python) would be desirable.
3. Passion for astrophysical research, Independent thinking, and hard working