Hi, I'm Quang H. Tran.

I am an incoming a 51 Pegasi b Fellow at Yale University. I am defending my PhD on July 24th, 2024 from the University of Texas, Austin. There, I worked with Prof. Brendan P. Bowler on topics like giant planets, young stars, stellar variability, and astrostatistics.

I'm generally excited about all things astronomy, so if you are interested in my work or collaborating, please take a look at my CV or contact me below!

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About Me

I am primarily interested in the migration and evolution of giant planetary systems. I also hunt for exoplanets using precision radial velocities from the ground and photometry from space.

My current research projects focus on searching for giant planets around young stars using precision radial velocities. I am also working on how best to model stellar activity signals in astronomical time series data (particularly with Gaussian process regression). In general, I want to understand underlying, population-level demographics and constrain the evolution of planets through probabilistic data analysis techniques.

When I'm not doing research, I enjoy weightlifting, being bad at pool (always down for a game), and searching for the best boba milk tea (ask for recs!).

Research Interests

Evolution & Migration of Giant Planets

One of my primary research interests is how the orbits of giant planets evolve over time. To answer this question, I led a 4-year precision radial velocity (PRV) survey targeting 100 intermediate-age (~20-200 Myr) Sun-like (GK dwarf) stars with the Habitable-zone Planet Finder (HPF) spectrograph. This survey is designed to measure the occurrence rate of close-in (a < 2.5 AU) giant planets, compare this value with the frequency at older ages, and determine the dominant migration mechanism of giant planets and its characteristic timescale (see right!). The first paper describing the survey design, data reduction pipeline, and initial results can be found below (left). The first discovery to emerge from the survey, the young hot Jupiter candidate HS Psc b, can also be found below (right)!

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Characterizing Individual Systems,
Inferring Population Statistics

Another approach I take to this question is the characterization of systems hosting giant planets. By performing detailed studies of systems with uncommon architectures, we can build a sample large enough to infer population-level statistics and trends.

One such system was TOI-1670, which hosted an inner Sub-Neptune and outer warm Jupiter (WJ) (see left). The modest population of systems with this unique configuration all have near-zero orbital eccentricties, whereas the eccentricities of other WJs are more widely distributed (see left), suggesting that these systems may have formed and migrated along a similar evolutionary pathway. For more information, see the paper below!

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Modeling Stellar Activity Signals
(with Gaussian Processes)

Detection limits for low mass, Earth-sized planets and planets around young, active stars are increasingly dominated by intrinsic stellar variability. To conduct population-level inference and detailed individual studies on these interesting systems, we need advanced methods that can distinguish non-dynamical variations from Keplerian motion.

I used the starry (Luger et al. 2019) open software package to simulate quasi-periodic, spot-drive activity signals in photometry and RVs (right, top panel). Then, I created a Gaussian process framework that simultaneously models stellar variability in both photometry and RVs. Using the synthetic dataset above, I demonstrate that this Two Latent GP approach can predict spot-driven RV variations with greater accuracy than other GP approaches (right, bottom three panels). For more information on how to simulate time series with starry or the 2 GP framework, check out the paper below!

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Curriculum Vitae CV logo Full CV [pdf]

Education

2018, The University of Chicago
A.B., Physics with a Concentration in Astrophysics
Thesis: The Distance to Sculptor via RR Lyrae Period-Luminosity Relations
Advisor: Dr. Wendy L. Freedman
2021, The University of Texas at Austin
M.A., Astronomy
Thesis: Near-Infrared Radial Velocity Jitter of Young Sun-like Stars
Advisor: Dr. Brendan P. Bowler
2024, The University of Texas at Austin
Ph.D., Astronomy
Thesis: The Epoch of Giant Planet Migration: Searching for Young Planets in the Stellar Noise
Advisor: Dr. Brendan P. Bowler

Select Awards & Honors Select PI Observing Programs

Fred T. Goetting Jr. Memorial Endowed Presidential Scholarship (2021) Hobby-Eberly Telescope (HPF), 442.5 hours

Flatiron Institute CCA Pre-doctoral Fellow (2021) Gemini-North Telescope (MAROON-X), 12.8 hours

NASA FINESST Grant Recipient (2020-2023) WIYN Observatory (NEID), 3.79 nights

UT Austin Graduate School Outstanding Master’s Thesis (2020) WIYN Observatory (NESSI), 1.5 nights

McDonald Observatory BOV Outstanding Master's Defense Award (2020) Harlan J. Smith Telescope (Tull Spectrograph), 15 nights