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A sub-Neptune sized planet transiting the M2.5-dwarf G 9-40: Validation with the Habitable-zone Planet Finder
Gudmundur Stefansson, Caleb Cañas, John Wisniewski +32
We validate the discovery of a 2 Earth radii sub-Neptune-size planet around the nearby high proper motion M2.5-dwarf G 9-40 (EPIC 212048748), using high-precision near-infrared (NI…
Evidence for He I 10830 Å~ absorption during the transit of a warm Neptune around the M-dwarf GJ 3470 with the Habitable-zone Planet Finder
Joe P. Ninan, Gudmundur Stefansson, Suvrath Mahadevan +21
Understanding the dynamics and kinematics of out-flowing atmospheres of hot and warm exoplanets is crucial to understanding the origins and evolutionary history of the exoplanets n…
Improving the Thermal Stability of a CCD Through Clocking
Cullen H. Blake, Dan Li, Joseph R. Tufts +6
Modern precise radial velocity spectrometers are designed to infer the existence of planets orbiting other stars by measuring few-nm shifts in the positions of stellar spectral lin…
It takes two planets in resonance to tango around K2-146
Kristine W. F. Lam, Judith Korth, Kento Masuda +51
K2-146 is a cool, 0.358 M_sun dwarf that was found to host a mini-Neptune with a 2.67-days period. The planet exhibited strong transit timing variations (TTVs) of greater than 30 m…
Constraining Exoplanet Metallicities and Aerosols with ARIEL: An Independent Study by the Contribution to ARIEL Spectroscopy of Exoplanets (CASE) Team
Robert T. Zellem, Mark R. Swain, Nicolas B. Cowan +24
Launching in 2028, ESA's Atmospheric Remote-sensing Exoplanet Large-survey (ARIEL) survey of 1000 transiting exoplanets will build on the legacies of Kepler and TESS and comp…
First Light of Engineered Diffusers at the Nordic Optical Telescope Reveal Time Variability in the Optical Eclipse Depth of WASP-12b
C. von Essen, G. Stefansson, M. Mallonn +6
We present the characterization of two engineered diffusers mounted on the 2.5 meter Nordic Optical Telescope, located at Roque de Los Muchachos, Spain. To assess the reliability a…
Impact of crosshatch patterns in H2RGs on high precision radial velocity measurements: Exploration of measurement and mitigation paths with HPF
Joe P. Ninan, Suvrath Mahadevan, Gudmundur Stefansson +9
Teledyne's H2RG detector images suffer from cross-hatch like patterns which arises from sub-pixel quantum efficiency (QE) variation. In this paper we present our measurements of th…
Mass-Radius relationship for M dwarf exoplanets: Comparing nonparametric and parametric methods
Shubham Kanodia, Angie Wolfgang, Gudmundur K. Stefansson +2
M dwarfs, though the most abundant star in the galaxy, form only a small subset of stellar hosts with exoplanets with measured radii and masses. In this paper we analyze the Mass-R…
Ultra-Stable Environment Control for the NEID Spectrometer: Design and Performance Demonstration
Paul Robertson, Tyler Anderson, Gudmundur Stefansson +30
Two key areas of emphasis in contemporary experimental exoplanet science are the detailed characterization of transiting terrestrial planets, and the search for Earth analog planet…
The Apache Point Observatory Galactic Evolution Experiment (APOGEE) Spectrographs
J. C. Wilson, F. R. Hearty, M. F. Skrutskie +86
We describe the design and performance of the near-infrared (1.51--1.70 micron), fiber-fed, multi-object (300 fibers), high resolution (R = lambda/delta lambda ~ 22,500) spectrogra…
TOI-150: A transiting hot Jupiter in the TESS southern CVZ
Caleb I. Cañas, Gudmundur Stefansson, Andrew J. Monson +23
We report the detection of a hot Jupiter (, ) orbiting a middle-aged star () in the Tra…
Stellar Spectroscopy in the Near-infrared with a Laser Frequency Comb
Andrew J. Metcalf, Tyler Anderson, Chad F. Bender +34
The discovery and characterization of exoplanets around nearby stars is driven by profound scientific questions about the uniqueness of Earth and our Solar System, and the conditio…
Kepler-730: A hot Jupiter system with a close-in, transiting, Earth-sized planet
Caleb I. Cañas, Songhu Wang, Suvrath Mahadevan +9
Kepler-730 is a planetary system hosting a statistically validated hot Jupiter in a 6.49-day orbit and an additional transiting candidate in a 2.85-day orbit. We use spectroscopic…