activity
20242026
collaborators

9 papers

astro-ph.EP2026

Leveraging Impact Parameter to Mitigate the Transit Light Source Effect: Early Insights from TRAPPIST-1

Ana Glidden, Alexander I. Shapiro, Sara Seager +19

Stellar activity complicates exoplanet transmission spectra, particularly for smaller planets around M dwarfs with JWST. The transit light source (TLS) effect, the imprinting of sp…

astro-ph.SR2026

The rotation-magnetism relationship in solar-type stars. Constraining magnetic flux emergence rates

Emre Isik, Sami K. Solanki, Natalie A. Krivova +1

The rotation-activity relationship of G-type stars results from surface magnetic fields emerging from the interior. How the magnetic flux and its emergence rate scale with rotation…

astro-ph.SR2026

Simulations of facular magnetic fields on cool stars I: Main sequence stars with solar metallicity

Tanayveer Singh Bhatia, Robert H. Cameron, Sami K. Solanki +4

Stellar convection in the presence of magnetic field affects the emergent intensity, as well as the structure and evolution of cool main-sequence dwarfs. We aim to understand the e…

astro-ph.EP2025

Flares on TRAPPIST-1 reveal the spectrum of magnetic features on its surface

Valeriy Vasilyev, Nadiia Kostogryz, Alexander I. Shapiro +11

TRAPPIST-1 is an M8 dwarf hosting seven known exoplanets and is currently one of the most frequently observed targets of the James Webb Space Telescope (JWST). However, it is notor…

astro-ph.SR2025

Detectability of Solar Rotation Period Across Various Wavelengths

Valeriy Vasilyev, Timo Reinhold, Alexander I. Shapiro +3

The light curves of old G-dwarfs obtained in the visible and near-infrared wavelength ranges are highly irregular. This significantly complicates the detectability of the rotation…

astro-ph.SR2024

Sun-like stars produce superflares roughly once per century

Valeriy Vasilyev, Timo Reinhold, Alexander I. Shapiro +7

Stellar superflares are energetic outbursts of electromagnetic radiation, similar to solar flares but releasing more energy, up to erg on main sequence stars. It is unkno…