53 citations · 213 across the 40 of their papers we have counts for
22 papers · 1 filter
An Obliquity Measurement of the Hot Neptune TOI-1694b
Luke B. Handley, Andrew W. Howard, Ryan A. Rubenzahl +9
We present spectral observations of the multiplanet host TOI-1694 during the transit of TOI-1694b, a 26.1 hot Neptune with a 3.77-day orbit. By analyzing radial velociti…
Ages of Stars and Planets in the Kepler Field Younger Than Four Billion Years
Luke G. Bouma, Lynne A. Hillenbrand, Andrew W. Howard +3
Recent analyses of FGK stars in open clusters have helped clarify the precision with which a star's rotation rate and lithium content can be used as empirical indicators for its ag…
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…
The HD 191939 Exoplanet System is Well-Aligned and Flat
Jack Lubin, Erik A. Petigura, Judah Van Zandt +25
We report the sky-projected spin-orbit angle for HD 191939 b, the innermost planet in a 6 planet system, using Keck/KPF to detect the Rossiter-McLaughlin (RM) effect. Planet b…
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…
Obliquities of Exoplanet Host Stars: 19 New and Updated Measurements, and Trends in the Sample of 205 Measurements
Emil Knudstrup, Simon H. Albrecht, Joshua N. Winn +17
Measurements of the obliquities in exoplanet systems have revealed some remarkable architectures, some of which are very different from the Solar System. Nearly 200 obliquity measu…
The 50-Myr-Old TOI-942c is Likely on an Aligned, Coplanar Orbit and Losing Mass
Huan-Yu Teng, Fei Dai, Andrew W. Howard +4
We report the observation of the transiting planet TOI-942c, a Neptunian planet orbiting a young K-type star approximately 50 Myr years old. Using Keck/HIRES, we observed a partial…
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…
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…
Obliquity Constraints for the Extremely Eccentric Sub-Saturn Kepler-1656 b
Ryan A. Rubenzahl, Andrew W. Howard, Samuel Halverson +25
The orbits of close-in exoplanets provide clues to their formation and evolutionary history. Many close-in exoplanets likely formed far out in their protoplanetary disks and migrat…
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…
Additional Doppler Monitoring Corroborates HAT-P-11 c as a Planet
Samuel W. Yee, Erik A. Petigura, Howard Isaacson +15
In 2010, Bakos and collaborators discovered a Neptune-sized planet transiting the K-dwarf HAT-P-11 every five days. Later in 2018, Yee and collaborators reported an additional Jovi…
A Testbed for Tidal Migration: the 3D Architecture of an Eccentric Hot Jupiter HD 118203 b Accompanied by a Possibly Aligned Outer Giant Planet
Jingwen Zhang, Daniel Huber, Lauren M. Weiss +31
Characterizing outer companions to hot Jupiters plays a crucial role in deciphering their origins. We present the discovery of a long-period giant planet, HD 118203 c ($m_{c}=11.79…
The OATMEAL Survey. I. Low Stellar Obliquity in the Transiting Brown Dwarf System GPX-1
Steven Giacalone, Fei Dai, J. J. Zanazzi +31
We introduce the OATMEAL survey, an effort to measure the obliquities of stars with transiting brown dwarf companions. We observed a transit of the close-in ($P_{\rm orb} = 1.74 \,…
The California Legacy Survey V. Chromospheric Activity Cycles in Main Sequence Stars
Howard Isaacson, Andrew W. Howard, Benjamin Fulton +31
We present optical spectroscopy of 710 solar neighborhood stars collected over twenty years to catalog chromospheric activity and search for stellar activity cycles. The California…
The TESS-Keck Survey XX: 15 New TESS Planets and a Uniform RV Analysis of all Survey Targets
Alex S. Polanski, Jack Lubin, Corey beard +69
The Transiting Exoplanet Survey Satellite (TESS) has discovered hundreds of new worlds, with TESS planet candidates now outnumbering the total number of confirmed planets from $\te…
A New Asteroseismic Benchmark Constrains the Onset of Weakened Magnetic Braking in Mature Sun-Like Stars
Vanshree Bhalotia, Daniel Huber, Jennifer L. van Saders +11
Stellar spin down is a critical yet poorly understood component of stellar evolution. In particular, results from the Kepler Mission imply that mature age, solar-type stars have in…
The TESS-Keck Survey. XXII. A sub-Neptune Orbiting TOI-1437
Daria Pidhorodetska, Emily A. Gilbert, Stephen R. Kane +40
Exoplanet discoveries have revealed a dramatic diversity of planet sizes across a vast array of orbital architectures. Sub-Neptunes are of particular interest; due to their absence…
Giant Outer Transiting Exoplanet Mass (GOT `EM) Survey. V. Two Giant Planets in Kepler-511 but Only One Ran Away
Yayaati Chachan, Paul A. Dalba, Daniel P. Thorngren +6
Systems hosting multiple giant planets are important laboratories for understanding planetary formation and migration processes. We present a nearly decade-long Doppler spectroscop…
A population of neutron star candidates in wide orbits from Gaia astrometry
Kareem El-Badry, Hans-Walter Rix, David W. Latham +10
We report discovery and spectroscopic follow-up of 21 astrometric binaries containing solar-type stars and dark companions with masses near 1.4 . The simplest interpreta…
A Perfect Tidal Storm: HD 104067 Planetary Architecture Creating an Incandescent World
Stephen R. Kane, Tara Fetherolf, Zhexing Li +5
The discovery of planetary systems beyond the solar system has revealed a diversity of architectures, most of which differ significantly from our system. The initial detection of a…
ESPRESSO observations of Gaia BH1: high-precision orbital constraints and no evidence for an inner binary
Pranav Nagarajan, Kareem El-Badry, Amaury H. M. J. Triaud +9
We present high-precision radial velocity (RV) observations of Gaia BH1, the nearest known black hole (BH). The system contains a solar-type G star orbiting a massive dark companio…