List of works - Gudmundur Stefansson

A 38 Million Year Old Neptune-sized Planet in the Kepler Field

scientific article published on 09 February 2022

A Candidate Transit Event around Proxima Centauri

A Harsh Test of Far-field Scrambling with the Habitable-zone Planet Finder and the Hobby–Eberly Telescope

scientific article published on 30 April 2021

A High-Eccentricity Warm Jupiter Orbiting TOI-4127

scientific article published in 2023

A Large and Variable Leading Tail of Helium in a Hot Saturn Undergoing Runaway Inflation

A Mini-Neptune and a Radius Valley Planet Orbiting the Nearby M2 Dwarf TOI-1266 in Its Venus Zone: Validation with the Habitable-zone Planet Finder

scientific article published on 13 November 2020

A Search for Planetary Metastable Helium Absorption in the V1298 Tau System

scientific article published in November 2021

A Second Planet Transiting LTT 1445A and a Determination of the Masses of Both Worlds

scientific article published on 14 March 2022

A Snowball in Hell: The Potential Steam Atmosphere of TOI-1266c

scientific article published in February 2022

A Sub-Neptune-sized Planet Transiting the M2.5 Dwarf G 9-40: Validation with the Habitable-zone Planet Finder

A Tendency Toward Alignment in Single-Star Warm Jupiter Systems

scientific article published in September 2022

A Warm Jupiter Transiting an M Dwarf: A TESS Single-transit Event Confirmed with the Habitable-zone Planet Finder

A Wolf 359 in sheep's clothing: Hunting for substellar companions in the fifth-closest system using combined high-contrast imaging and radial velocity analysis

A blue ring nebula from a stellar merger several thousand years ago

scientific article published on 18 November 2020

A close-in puffy Neptune with hidden friends: The enigma of TOI 620

scientific article

A hot Mars-sized exoplanet transiting an M dwarf

scientific article published in 2022

A versatile technique to enable sub-milli-Kelvin instrument stability for precise radial velocity measurements: tests with the habitable-zone planet finder ⬇️

scientific article published in the Astrophysical Journal

An In-Depth Look at TOI-3884b: a Super-Neptune Transiting a M4 Dwarf with Persistent Star Spot Crossings

An In-depth Look at TOI-3884b: A Super-Neptune Transiting an M4Dwarf with Persistent Starspot Crossings

scientific article published on 24 May 2023

An extreme test case for planet formation: a close-in Neptune orbiting an ultracool star

scientific article published in December 2023

Association of Copy Number Variation of the 15q11.2 BP1-BP2 Region With Cortical and Subcortical Morphology and Cognition

scientific article published on 30 October 2019

Characterization of low-mass companions to $\textit{Kepler}$ objects of interest observed with APOGEE-N

Correction: Dose response of the 16p11.2 distal copy number variant on intracranial volume and basal ganglia

scientific article published on 01 March 2020

Environmental control system for Habitable-zone Planet Finder (HPF)

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

scientific article published on 11 May 2020

GJ 3929: High Precision Photometric and Doppler Characterization of an Exo-Venus and its Hot, Mini-Neptune-mass Companion

Gaia 20eae: A Newly Discovered Episodically Accreting Young Star

scientific article published in February 2022

Giant Tidal Tails of Helium Escaping the Hot Jupiter HAT-P-32 b ⬇️

scientific article published on 9 June 2023

High-resolution Near-infrared Spectroscopy of a Flare around the Ultracool Dwarf vB 10

scientific article published in February 2022

Impact of crosshatch patterns in H2RGs on high-precision radial velocity measurements: exploration of measurement and mitigation paths with the Habitable-Zone Planet Finder

scientific article published on 26 October 2019

Measuring the Obliquities of the TRAPPIST-1 Planets with MAROON-X

scientific article published on 24 February 2023

Measuring the Temperature of Starspots from Multi-filter Photometry

scientific article published on 4 August 2023

Modeling Stellar Surface Features on a Subgiant Star with an M-dwarf Companion

scientific article published on 17 June 2022

NEID Reveals that The Young Warm Neptune TOI-2076 b Has a Low Obliquity

scientific article published in February 2023

Nondetection of Helium in the Upper Atmospheres of TRAPPIST-1b, e, and f

scientific article published on 2 August 2021

Observing the Sun as a Star: Design and Early Results from the NEID Solar Feed

scientific article published on 22 March 2022

Persistent Starspot Signals on M Dwarfs: Multiwavelength Doppler Observations with the Habitable-zone Planet Finder and Keck/HIRES

scientific article published on 9 July 2020

Rotational Modulation of Spectroscopic Zeeman Signatures in Low-mass Stars

scientific article published in March 2022

Solar Contamination in Extreme-precision Radial-velocity Measurements: Deleterious Effects and Prospects for Mitigation

scientific article published on 18 March 2020

Stable Fiber-illumination for Extremely Precise Radial Velocities with NEID

scientific article published on 15 August 2023

Stellar Activity Manifesting at a One-year Alias Explains Barnard b as a False Positive

scientific article published on 15 July 2021

Stellar spectroscopy in the near-infrared with a laser frequency comb

scientific article published on 20 February 2019

TOI-1696 and TOI-2136: Constraining the Masses of Two Mini-Neptunes with HPF

scholarly article

TOI-1728b: The Habitable-zone Planet Finder Confirms a Warm Super-Neptune Orbiting an M-dwarf Host

scientific article published on 10 August 2020

TOI-3785 b: A Low-Density Neptune Orbiting an M2-Dwarf Star

scientific article published in April 2023

TOI-3984 A b and TOI-5293 A b: two temperate gas giants transiting mid-M dwarfs in wide binary systems

scientific article published in 2023

TOI-4201: An Early M-dwarf Hosting a Massive Transiting Jupiter Stretching Theories of Core-Accretion

scientific article published in February 2024

TOI-5205b: A Jupiter transiting an M dwarf near the Convective Boundary

scientific article published on 21 February 2023

TOI-532b: The Habitable-zone Planet Finder confirms a Large Super Neptune in the Neptune Desert orbiting a metal-rich M dwarf host

scientific article published in 2021

TOI-5375 B: A Very Low Mass Star at the Hydrogen-burning Limit Orbiting an Early M-type Star

scientific article published on 28 April 2023

TOI-561 b: A Low Density Ultra-Short Period "Rocky" Planet around a Metal-Poor Star

scientific article published on 7 February 2023

TOI-663: A newly discovered multi-planet system with three transiting mini-Neptunes orbiting an early M star

scientific article published in May 2024

The Aligned Orbit of WASP-148b, the Only Known Hot Jupiter with a nearby Warm Jupiter Companion, from NEID and HIRES

scientific article published in February 2022

The Aligned Orbit of the Eccentric Proto Hot Jupiter TOI-3362b

The Death of Vulcan: NEID Reveals That the Planet Candidate Orbiting HD 26965 Is Stellar Activity ⬇️

journal article from 'The Astronomical Journal' published in 2024

The Habitable Zone Planet Finder Reveals a High Mass and Low Obliquity for the Young Neptune K2-25b

The Habitable-Zone Planet Finder: improved flux image generation algorithms for H2RG up-the-ramp data

scientific article published on 2 August 2018

The Habitable-zone Planet Finder Detects a Terrestrial-mass Planet Candidate Closely Orbiting Gliese 1151: The Likely Source of Coherent Low-frequency Radio Emission from an Inactive Star

The unusual M-dwarf Warm Jupiter TOI-1899~b: Refinement of orbital and planetary parameters

scientific article published on 3 August 2023

Toward Space-like Photometric Precision from the Ground with Beam-shaping Diffusers

scientific article published in the Astrophysical Journal

List of works by Gudmundur Stefansson

A 38 Million Year Old Neptune-sized Planet in the Kepler Field

A Candidate Transit Event around Proxima Centauri

A Harsh Test of Far-field Scrambling with the Habitable-zone Planet Finder and the Hobby–Eberly Telescope

A High-Eccentricity Warm Jupiter Orbiting TOI-4127

A Large and Variable Leading Tail of Helium in a Hot Saturn Undergoing Runaway Inflation

A Mini-Neptune and a Radius Valley Planet Orbiting the Nearby M2 Dwarf TOI-1266 in Its Venus Zone: Validation with the Habitable-zone Planet Finder

A Search for Planetary Metastable Helium Absorption in the V1298 Tau System

A Second Planet Transiting LTT 1445A and a Determination of the Masses of Both Worlds

A Snowball in Hell: The Potential Steam Atmosphere of TOI-1266c

A Sub-Neptune-sized Planet Transiting the M2.5 Dwarf G 9-40: Validation with the Habitable-zone Planet Finder

A Tendency Toward Alignment in Single-Star Warm Jupiter Systems

A Warm Jupiter Transiting an M Dwarf: A TESS Single-transit Event Confirmed with the Habitable-zone Planet Finder

A Wolf 359 in sheep's clothing: Hunting for substellar companions in the fifth-closest system using combined high-contrast imaging and radial velocity analysis

A blue ring nebula from a stellar merger several thousand years ago

A close-in puffy Neptune with hidden friends: The enigma of TOI 620

A hot Mars-sized exoplanet transiting an M dwarf

A versatile technique to enable sub-milli-Kelvin instrument stability for precise radial velocity measurements: tests with the habitable-zone planet finder ⬇️

An In-Depth Look at TOI-3884b: a Super-Neptune Transiting a M4 Dwarf with Persistent Star Spot Crossings

An In-depth Look at TOI-3884b: A Super-Neptune Transiting an M4Dwarf with Persistent Starspot Crossings

An extreme test case for planet formation: a close-in Neptune orbiting an ultracool star

Association of Copy Number Variation of the 15q11.2 BP1-BP2 Region With Cortical and Subcortical Morphology and Cognition

Characterization of low-mass companions to $\textit{Kepler}$ objects of interest observed with APOGEE-N

Correction: Dose response of the 16p11.2 distal copy number variant on intracranial volume and basal ganglia

Environmental control system for Habitable-zone Planet Finder (HPF)

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

GJ 3929: High Precision Photometric and Doppler Characterization of an Exo-Venus and its Hot, Mini-Neptune-mass Companion

Gaia 20eae: A Newly Discovered Episodically Accreting Young Star

Giant Tidal Tails of Helium Escaping the Hot Jupiter HAT-P-32 b ⬇️

High-resolution Near-infrared Spectroscopy of a Flare around the Ultracool Dwarf vB 10

Impact of crosshatch patterns in H2RGs on high-precision radial velocity measurements: exploration of measurement and mitigation paths with the Habitable-Zone Planet Finder

Measuring the Obliquities of the TRAPPIST-1 Planets with MAROON-X

Measuring the Temperature of Starspots from Multi-filter Photometry

Modeling Stellar Surface Features on a Subgiant Star with an M-dwarf Companion

NEID Reveals that The Young Warm Neptune TOI-2076 b Has a Low Obliquity

Nondetection of Helium in the Upper Atmospheres of TRAPPIST-1b, e, and f

Observing the Sun as a Star: Design and Early Results from the NEID Solar Feed

Persistent Starspot Signals on M Dwarfs: Multiwavelength Doppler Observations with the Habitable-zone Planet Finder and Keck/HIRES

Rotational Modulation of Spectroscopic Zeeman Signatures in Low-mass Stars

Solar Contamination in Extreme-precision Radial-velocity Measurements: Deleterious Effects and Prospects for Mitigation

Stable Fiber-illumination for Extremely Precise Radial Velocities with NEID

Stellar Activity Manifesting at a One-year Alias Explains Barnard b as a False Positive

Stellar spectroscopy in the near-infrared with a laser frequency comb

TOI-1696 and TOI-2136: Constraining the Masses of Two Mini-Neptunes with HPF

TOI-1728b: The Habitable-zone Planet Finder Confirms a Warm Super-Neptune Orbiting an M-dwarf Host

TOI-3785 b: A Low-Density Neptune Orbiting an M2-Dwarf Star

TOI-3984 A b and TOI-5293 A b: two temperate gas giants transiting mid-M dwarfs in wide binary systems

TOI-4201: An Early M-dwarf Hosting a Massive Transiting Jupiter Stretching Theories of Core-Accretion

TOI-5205b: A Jupiter transiting an M dwarf near the Convective Boundary

TOI-532b: The Habitable-zone Planet Finder confirms a Large Super Neptune in the Neptune Desert orbiting a metal-rich M dwarf host

TOI-5375 B: A Very Low Mass Star at the Hydrogen-burning Limit Orbiting an Early M-type Star

TOI-561 b: A Low Density Ultra-Short Period "Rocky" Planet around a Metal-Poor Star

TOI-663: A newly discovered multi-planet system with three transiting mini-Neptunes orbiting an early M star

The Aligned Orbit of WASP-148b, the Only Known Hot Jupiter with a nearby Warm Jupiter Companion, from NEID and HIRES

The Aligned Orbit of the Eccentric Proto Hot Jupiter TOI-3362b

The Death of Vulcan: NEID Reveals That the Planet Candidate Orbiting HD 26965 Is Stellar Activity ⬇️

The Habitable Zone Planet Finder Reveals a High Mass and Low Obliquity for the Young Neptune K2-25b

The Habitable-Zone Planet Finder: improved flux image generation algorithms for H2RG up-the-ramp data

The Habitable-zone Planet Finder Detects a Terrestrial-mass Planet Candidate Closely Orbiting Gliese 1151: The Likely Source of Coherent Low-frequency Radio Emission from an Inactive Star

The unusual M-dwarf Warm Jupiter TOI-1899~b: Refinement of orbital and planetary parameters

Toward Space-like Photometric Precision from the Ground with Beam-shaping Diffusers

Updated Planetary Mass Constraints of the Young V1298 Tau System Using MAROON-X