activity
20242026
collaborators

7 papers

astro-ph.EP2026

CHEOPS observations of V1298 Tau: updated planetary densities and implications on the early evolution of the young system

Hinna Shivkumar, Sérgio Gomes, Jean-Michel Désert +9

The young (10-30 Myr) multi-planet system V1298 Tau presents a unique opportunity to probe the early formation and evolution of young systems. We present new CHEOPS observations of…

astro-ph.EP2026

The NUV transit of XO-3 b

Raven Cilley, Lia Corrales, George W. King +8

Near-UV (NUV) measurements of exoplanet transits offer a means to probe atmospheric escape, cloud formation, and planetary magnetic fields. We examine a 2024 XMM-Newton Optical Mon…

astro-ph.EP2026

Confirmation of Fe I on MASCARA-5 b's Dayside Observed With EXPRES

James T. Sikora, Joe Llama, Rachael M. Roettenbacher +5

MASCARA-5~b/TOI-1431~b is an ultra-hot Jupiter \citep[, , , $R_{\rm p}=…

astro-ph.SR2025

The He I D3 Line as a Proxy for Magnetic Activity using EXPRES Solar Observations

Momo Ellwarth, Joe Llama, Lily L. Zhao +6

Stellar activity remains one of the primary challenges in the detection and characterization of low-mass exoplanets, as it can induce radial velocity (RV) variations that mask or m…

astro-ph.EP2025

Seasonal Changes in the Atmosphere of HD 80606b Observed with JWST's NIRSpec/G395H

James T. Sikora, Jason F. Rowe, Jared Splinter +11

High-eccentricity gas giant planets serve as unique laboratories for studying the thermal and chemical properties of H/He-dominated atmospheres. One of the most extreme cases is HD…

astro-ph.EP2025

A metal-poor atmosphere with a hot interior for a young sub-Neptune progenitor: JWST/NIRSpec transmission spectrum of V1298 Tau b

Saugata Barat, Jean-Michel Désert, Sagnick Mukherjee +19

We present the JWST/NIRSpec G395H transmission spectrum of the young (10 - 20 Myr old) transiting planet V1298 Tau b (9.85+/-0.35 Re, Teq=670K). Combined HST and JWST observations…