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20202026
most citedWASP-107b's density is even lower: a case study for the physics of planetary gas envelope accretion and orbital migration

97 citations · 999 across the 70 of their papers we have counts for

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20 papers · 1 filter

astro-ph.EP2024

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…

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.EP2024

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…

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

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…

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

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…

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

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…

astro-ph.EP2024

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…

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 \,…

astro-ph.SR2024

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…

astro-ph.EP2024★ 53 cited

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…

astro-ph.EP2024

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…

astro-ph.EP2024★ 2 cited

The TESS-Keck Survey XXI: 13 New Planets and Homogeneous Properties for 21 Subgiant Systems

Ashley Chontos, Daniel Huber, Samuel K. Grunblatt +67

We present a dedicated transit and radial velocity survey of planets orbiting subgiant stars observed by the TESS Mission. Using nights on Keck/HIRES, we confirm and cha…

astro-ph.EP2024

The TESS-Keck Survey. XII. A Dense 1.8 R Ultra-Short-Period Planet Possibly Clinging to a High-Mean-Molecular-Weight Atmosphere After the First Gyr

Ryan A. Rubenzahl, Fei Dai, Andrew W. Howard +39

The extreme environments of ultra-short-period planets (USPs) make excellent laboratories to study how exoplanets obtain, lose, retain, and/or regain gaseous atmospheres. We presen…

astro-ph.EP2024

The TESS-Keck Survey. XVIII. A sub-Neptune and spurious long-period signal in the TOI-1751 system

Anmol Desai, Emma V. Turtelboom, Caleb K. Harada +37

We present and confirm TOI-1751 b, a transiting sub-Neptune orbiting a slightly evolved, solar-type, metal-poor star ( K, , V = 9.3 ma…

astro-ph.EP2024★ 1 cited

The TESS-Keck Survey. XIX. A Warm Transiting Sub-Saturn Mass Planet and a non-Transiting Saturn Mass Planet Orbiting a Solar Analog

Michelle L. Hill, Stephen R. Kane, Paul A. Dalba +45

The Transiting Exoplanet Survey Satellite (TESS) continues to dramatically increase the number of known transiting exoplanets, and is optimal for monitoring bright stars amenable t…

astro-ph.EP2024

Giant Outer Transiting Exoplanet Mass (GOT 'EM) Survey. IV. Long-term Doppler Spectroscopy for 11 Stars Thought to Host Cool Giant Exoplanets

Paul A. Dalba, Stephen R. Kane, Howard Isaacson +29

Discovering and characterizing exoplanets at the outer edge of the transit method's sensitivity has proven challenging owing to geometric biases and the practical difficulties asso…