papers

Publications (17)

astro-ph.EP2025

PEPSI Investigation, Retrieval, and Atlas of Numerous Giant Atmospheres (PIRANGA). IV. High-Resolution Phased-Resolved Spectroscopy of The Ultra Hot Jupiter KELT-20 b

Victoria Bonidie, Marshall C. Johnson, Ji Wang +7

We present five datasets of high-resolution optical emission spectra of the ultra-hot Jupiter KELT-20 b with the PEPSI spectrograph. Using a Bayesian retrieval framework, we constr…

astro-ph.SR2024

BEBOP V. Homogeneous Stellar Analysis of Potential Circumbinary Planet Hosts

Alix V. Freckelton, Daniel Sebastian, Annelies Mortier +29

Planets orbiting binary systems are relatively unexplored compared to those around single stars. Detections of circumbinary planets and planetary systems offer a first detailed vie…

astro-ph.EP2025

Are We There Yet? Challenges in Quantifying the Frequency of Earth Analogs in the Habitable Zone

Rachel B. Fernandes, Samson Johnson, Galen J. Bergsten +43

Searching for life elsewhere in the universe is one of the most highly prioritized pursuits in astronomy today. However, the ability to observe evidence of Earth-like life through…

astro-ph.SR2025

The EBLM project XVI. Moderate spin-orbit misalignment of the low mass eclipsing binary EBLM J0021-16

Becca Spejcher, David V. Martin, Jake Pandina +15

Thousands of tight ( AU) main sequence binaries have been discovered, but it is uncertain how they formed. There is likely too much angular momentum in a collapsing, fragmentin…

astro-ph.SR2025

The EBLM Project XVIII. 3D Obliquities of Five Low-Mass Eclipsing Binaries

Becca Spejcher, David V. Martin, Jake Pandina +19

A question that continues to perplex astronomers is the formation of tight stellar binaries. There is too much angular momentum in a collapsing and fragmenting protostellar cloud t…

astro-ph.SR2026

Benchmark Brown Dwarf Systems I: Chemical Abundance Analysis of FGK Stars with Wide-Separation Brown Dwarf Companions Using PEPSI

Caprice L. Phillips, Megan Bedell, Catherine Manea +11

The authors performed a high‑resolution spectroscopic survey of 32 FGK stars that host wide‑separation brown dwarf companions, deriving precise stellar parameters and abundances fo…

#brown dwarfs#stellar abundances#high-resolution spectroscopy#FGK host stars
astro-ph.EP2026

Technique-agnostic exoplanet demography for the Roman era -- I. Testing a demography retrieval framework using simulated Kepler-like transit datasets

Akshay Priyadarshi, Eamonn Kerins, Michael D. Albrow +41

The Nancy Grace Roman Space Telescope (Roman) will unveil for the first time the full architecture of planetary systems across Galactic distances through the discovery of up to 200…

astro-ph.EP2021

K2, Spitzer, and TESS Transits of Four Sub-Neptune Exoplanets

Alison Duck, Caleb K. Harada, Justin Harrell +5

We present new Spitzer transit observations of four K2 transiting sub-Neptunes: K2-36c, K2-79b, K2-167b, and K2-212b. We derive updated orbital ephemerides and radii for these plan…

astro-ph.SR2022

Revised Temperatures For Two Benchmark M-dwarfs -- Outliers No More

David V. Martin, Tayt Armitage, Alison Duck +7

Well-characterised M-dwarfs are rare, particularly with respect to effective temperature. In this letter we re-analyse two benchmark M-dwarfs in eclipsing binaries from Kepler/K2:…

astro-ph.SR2026

EBLM XVII - Tidal Synchronization and Circularization in Tight Stellar Binaries

Ritika Sethi, David V. Martin, Adrian Barker +7

Tidal interactions in close stellar binaries are central to their orbital and rotational evolution, making observational tests of theoretical predictions essential for our understa…

astro-ph.SR2025

The EBLM project -- XIV. TESS light curves for eclipsing binaries with very low mass companions

Jay Fitzpatrick, Pierre F. L. Maxted, Alix V. Freckelton +3

Accurate limb-darkening models are needed for accurate characterisation of eclipsing binary stars and transiting exoplanets from the analysis of their light curves. The limb-darken…

astro-ph.SR2024

The EBLM Project XII. An eccentric, long-period eclipsing binary with a companion near the hydrogen-burning limit

Yasmin T. Davis, Amaury H. M. J. Triaud, Alix V. Freckelton +17

In the hunt for Earth-like exoplanets it is crucial to have reliable host star parameters, as they have a direct impact on the accuracy and precision of the inferred parameters for…

astro-ph.EP2024

Exploring Systematic Errors in the Inferred Parameters of the Transiting Planet KELT-15b and its Host Star

Alison Duck, B. Scott Gaudi, Jason D. Eastman +1

Transiting planet systems offer a unique opportunity to measure the masses and radii of many planets and their host stars. Yet, relative photometry and radial velocity measurements…

astro-ph.EP2025

PEPSI Investigation, Retrieval, and Atlas of Numerous Giant Atmospheres (PIRANGA). I. The Ubiquity of Fe I Emission and Inversions in Ultra Hot Jupiter Atmospheres

Sydney Petz, Marshall C. Johnson, Anusha Pai Asnodkar +4

We present high-resolution optical emission spectroscopy observations of the ultra hot Jupiters (UHJs) TOI-1431 b and TOI-1518 b using the PEPSI spectrograph on the LBT. We detect…

astro-ph.EP2025

PEPSI Investigation, Retrieval, and Atlas of Numerous Giant Atmospheres (PIRANGA). III. Composition and winds in the atmosphere of TOI-1518 b

Connor Basinger, Marshall C. Johnson, Ji Wang +6

Ultra-hot Jupiters (UHJs) orbit close to their host stars and experience extreme conditions, making them important laboratories to explore atmospheric composition and dynamics. Tra…

astro-ph.EP2025

PEPSI Investigation, Retrieval, and Atlas of Numerous Giant Atmospheres (PIRANGA). II. Phase-Resolved Cross-Correlation Transmission Spectroscopy of KELT-20b

Calder Lenhart, Marshall C. Johnson, Ji Wang +5

KELT-20b is a well-studied ( K) ultra hot Jupiter, but its multidimensional atmospheric structure remains unconstrained. We performed high-resolution cross-corr…

astro-ph.SR2024

The EBLM project X. Benchmark masses, radii and temperatures for two fully convective M-dwarfs using K2

Alison Duck, David V. Martin, Sam Gill +23

M-dwarfs are the most abundant stars in the galaxy and popular targets for exoplanet searches. However, their intrinsic faintness and complex spectra inhibit precise characterisati…