Research

My research is primarily centered around our home Galaxy, the Milky Way. What would a biography of our Galaxy look like? How has our Galaxy grown and evolved over time, and what does that teach us about other galaxies like our own? I seek answers to these questions primarily by designing and analyzing large stellar spectroscopic surveys, and extensively use theoretical and simulation-based predictions to interpret observational findings.

On this page I briefly summarize the major themes of my research, along with some representative publications that I’ve lead or co-lead. Projects on which I served as an advisor/mentor are highlighted with asterisks.

The Galactic Outskirts

The furthest stars in the Milky Way – to 100 kiloparsecs and beyond – hold a treasure trove of information about the recent accretion history of our Galaxy, including the outsize perturbations from the in-falling Magellanic Clouds. As a central part of my PhD, I designed and executed a tailor-made spectroscopic survey to obtain detailed measurements of hundreds of these distant stars, building an all-sky dataset to understand the outer galaxy.

A Ghost in Boötes: The Least-Luminous Disrupted Dwarf Galaxy

Distant Echoes of the Milky Way’s Last Major Merger

Discovery of the Magellanic Stellar Stream

Measuring the LMC-induced Reflex Motion of the Halo

The Evolution of the Milky Way

The Gaia space observatory has revolutionized our understanding of the Miky Way with 3D positions, velocities, and low-resolution spectroscopy of millions of stars. I have extensively worked on extracting scientific information from this rich dataset, and using its unprecedented size and fidelity to trace the formation history of our Galaxy.

Robust Data-driven Metallicities for 175 Million Stars from Gaia XP Spectra

The Poor Old Heart of the Milky Way

The Three-Phase Evolution of the Milky Way

The Via Project

The Via Project is an upcoming spectroscopic survey that will place twin high-resolution multi-object spectrographs on 6.5-meter telescopes covering both celestial hemispheres. I have played a central role in the Via project since it was first proposed, co-leading the science development and building software to simulate various aspects of the instrument and survey. I’m also involved in the opto-mechanical design of the ViaSpec instrument.

White Dwarf Stars

White dwarfs are compact stellar remnants left behind by all Sun-like stars. They are some of the best laboratories of general relativistic and quantum mechanical effects on macroscopic scales.

Computational tools for the spectroscopic analysis of white dwarfs

A Gravitational Redshift Measurement of the White Dwarf Mass-Radius Relation

Searching for Low-mass Population III Stars Disguised as White Dwarfs

A 99 minute Double-lined White Dwarf Binary from SDSS-V

The SN Ia runaway LP 398-9: detection of circumstellar material and surface rotation

*Discovery of a proto-white dwarf with a massive unseen companion

*Measuring the Mass–Radius Relation of White Dwarfs Using Wide Binaries