activity
20242026
most citedTESS Giants Transiting Giants. VI. Newly Discovered Hot Jupiters Provide Evidence for Efficient Obliquity Damping after the Main Sequence

13 citations · 27 across the 13 of their papers we have counts for

collaborators

14 papers

astro-ph.EP2026

Spin-Orbit Alignment of Two Neptune-size Planets Younger than 500 Myr: TOI-560 b and TOI-5082 b

Elina Y. Zhang, Fei Dai, Andrew W. Howard +25

Stellar obliquity measurements provide a direct probe of planetary system dynamics, but remain sparse for Neptune-size planets, particularly at young ages. We present Rossiter-McLa…

astro-ph.EP2026

The KPF-SLOPE Survey - Small, Compact Multi-Planet Systems Appear Spin-Orbit Aligned

Luke B. Handley, Andrew W. Howard, Fei Dai +16

The angle between stellar spin axes and planetary orbits -- stellar obliquity -- probes the dynamics of planetary migration and evolution. The obliquities of giant planets have bee…

astro-ph.EP2026

TOI-4495: A Pair of Aligned, Near-Resonant Sub-Neptunes that Likely Experienced Overstable Migration

Mu-Tian Wang, Fei Dai, Hui-Gen Liu +24

We report the discovery of a sub-Neptune and a Neptune-like planet (, ) orbiting the F-type star TOI-449…

astro-ph.SR2025

A Test of Substellar Evolutionary Models with High-Precision Ages from Asteroseismology and Gyrochronology for the Benchmark System HR 7672AB

Yaguang Li, Michael C. Liu, Trent J. Dupuy +35

We present high-precision measurements for HR~7672AB, composed of a Sun-like (G0V) star and an L~dwarf companion. Three nights of precise (70 cm/s) radial velocity (RV) asteroseism…

astro-ph.EP2025

The KPF SURFS-UP Survey I: Transmission Spectroscopy of WASP-76 b

Aaron Householder, Fei Dai, Aurora Kesseli +25

We introduce the KPF SURFS-UP (Spectroscopy of the Upper-atmospheres and ReFractory Species in Ultra-hot Planets) Survey, a high-resolution survey to investigate the atmospheric co…

astro-ph.EP2025

TOI-880 is an Aligned, Coplanar, Multi-planet System

Elina Y. Zhang, Huan-Yu Teng, Fei Dai +22

Although many cases of stellar spin-orbit misalignment are known, it is usually unclear whether a single planet's orbit was tilted or if the entire protoplanetary disk was misalign…

astro-ph.EP2025

Stellar Obliquity of the Ultra-Short-Period Planet System HD 93963

Huan-Yu Teng, Fei Dai, Andrew W. Howard +24

We report an observation of the Rossiter-McLaughlin (RM) effect of the transiting planet HD 93963 Ac, a mini-Neptune planet orbiting a G0-type star with an orbital period of $P_{\r…

astro-ph.SR2025

K-dwarf Radius Inflation and a 10-Gyr Spin-down Clock Unveiled through Asteroseismology of HD 219134 from the Keck Planet Finder

Yaguang Li, Daniel Huber, J. M. Joel Ong +26

We present the first asteroseismic analysis of the K3\,V planet host HD~219134, based on four consecutive nights of radial velocities collected with the Keck Planet Finder. We appl…

astro-ph.EP2024★ 1 cited

The Compositions of Rocky Planets in Close-in Orbits Tend to be Earth-Like

Casey L. Brinkman, Lauren M. Weiss, Daniel Huber +54

Hundreds of exoplanets between 1-1.8 times the size of the Earth have been discovered on close in orbits. However, these planets show such a diversity in densities that some appear…

astro-ph.SR2024

Asteroseismology of the Nearby K-Dwarf Draconis using the Keck Planet Finder and TESS

Marc Hon, Daniel Huber, Yaguang Li +76

Asteroseismology of dwarf stars cooler than the Sun is very challenging due to the low amplitudes and rapid timescales of oscillations. Here, we present the asteroseismic detection…

astro-ph.EP2024★ 13 cited

TESS Giants Transiting Giants. VI. Newly Discovered Hot Jupiters Provide Evidence for Efficient Obliquity Damping after the Main Sequence

Nicholas Saunders, Samuel K. Grunblatt, Ashley Chontos +53

The degree of alignment between a star's spin axis and the orbital plane of its planets (the stellar obliquity) is related to interesting and poorly understood processes that occur…

astro-ph.EP2024

KPF Confirms a Polar Orbit for KELT-18 b

Ryan A. Rubenzahl, Fei Dai, Samuel Halverson +24

We present the first spectroscopic transit results from the newly commissioned Keck Planet Finder on the Keck-I telescope at W. M. Keck Observatory. We observed a transit of KELT-1…

astro-ph.EP2024

An Earth-sized Planet on the Verge of Tidal Disruption

Fei Dai, Andrew W. Howard, Samuel Halverson +95

TOI-6255~b (GJ 4256) is an Earth-sized planet (1.079 ) with an orbital period of only 5.7 hours. With the newly commissioned Keck Planet Finder (KPF) and CARMEN…

astro-ph.EP2024★ 13 cited

The OATMEAL Survey. I. Low Stellar Obliquity in the Transiting Brown Dwarf System GPX-1

Steven Giacalone, Fei Dai, J. J. Zanazzi +31

We introduce the OATMEAL survey, an effort to measure the obliquities of stars with transiting brown dwarf companions. We observed a transit of the close-in ($P_{\rm orb} = 1.74 \,…