Dino Chih-Chun Hsu

Postdoctoral Researcher at Northwestern University CIERA
Studying low-mass stars, brown dwarfs, and gas giant exoplanets using high-resolution spectroscopy.

About Dino Hsu

Dino Chih-Chun Hsu is a postdoctoral researcher at Northwestern CIERA, working with Prof. Jason Wang. Before arriving at Evanston, northern Chicago, Dino obtained his Ph.D. in Physics at UC San Diego, where he worked with Prof. Adam Burgasser on the kinematics, rotation, and multiplicity using the near-infrared high-resolution spectroscopy including Keck/NIRSPEC and SDSS/APOGEE.

Forward-Modeling Method

I use a Markov Chain Monte Carlo (MCMC) forward-modeling method to model the high-resolution spectra and extract precise radial and projected rotational velocities, as well as surface temperatures and surface gravities for hundreds of nearby ultracool dwarfs.

Ultracool Dwarf Kinematics

Space motions of celestial objects tell us how their formation history and evolution. Using a forward-modeling method, I measured previse radial and projected rotational velocities of 37 T dwarfs. I compiled a local 3D kinematics sample of 172 late-M, L, and T dwarfs and found kinematic evidence of the stellar and substellar boundary.

Ultracool Dwarf Binaries

Binaries are a direct product of star formation. They provide measurements of mass, separation, orbital period and eccentricity which can be used to constrain the star formation models. Using the precise radial velocity (RV) using the forward-modeling method, I found the first RV-verified T dwarfs J1106+2754 and J2126+7617 and the shortest-orbital-period ultracool dwarf binary LP 413-53AB. I also contributed to RV measurements of a young ultracool dwarf (likely) triple system DENIS J0630+1840.

Ultracool Dwarf Rotation

The rotation of ultracool dwarfs tells us their angular momentum evolution. Stellar and substellar objects experience different phases of angular momentum evolution, which can be constrained using their rotational period (through photometric light curves) and projected rotational velocities (vsini) through high-resolution spectroscopy.

Rotation and Abundances of Gas Giant Exoplanets

More recently, I am working on a high-resolution spectroscopic survey to extract the gas giant planet using the Keck Planet Imager and Characterizer (KPIC; Mawet et al. 2017). The rotation (Wang et al. 2021) and abundances (Xuan et al. 2022) of gas exoplanets can provide us with their formation and evolution. Stay tuned for our future updates!

Teaching & Outreach

I had extensive teaching and outreach experience since my graduate studies at UC San Diego. During my Ph.D. at UC San Diego, I taught various classes with a total of 15 quarters of teaching experience.