164 citations · 685 across the 26 of their papers we have counts for
6 papers · 1 filter
Granulation in Color: The Chromatic Stellar Flicker of LTT-9779 and WASP-121
William C. Waalkes, Nadiia Kostogryz, Valeriy Vasilyev +9
Granulation is a persistent feature of stars with outer convective layers and is the photospheric signature of near-surface convective energy transport. In disk-integrated observat…
The Curious Case of Dark Faculae on M Dwarf Stars
Alexander~I. ~Shapiro, Sara~Seager, Sami~K. ~Solanki +6
The study of exoplanet atmospheres has brought a renewed interest in stellar astrophysics. Specifically, stellar magnetic activity from the host star contaminates exoplanet atmosph…
Overestimated Pressure Broadening Misleads Model Spectra in Cool M Dwarf Stars
Ana Glidden, Veronika Witzke, Alexander I. Shapiro +1
Available one-dimensional stellar models fail to reproduce the observed spectrum of the ultracool M dwarf TRAPPIST-1. In particular, current models predict strong iron hydride (FeH…
Molecular hydrogen controls the temperatures of flares on TRAPPIST-1
Alexander I. Shapiro Nadiia Kostogryz Sara Seager Veronika Witzke Julien de Wit Valeriy Vasilyev Astrid M. Veronig Robert Cameron Hardi Peter Sami K. Solanki
Early JWST observations of TRAPPIST-1 have revealed an unexpected puzzle: energetic white-light flares ( erg) reach temperatures of only 3500--4000\,K, ne…
PTFO 8-8695: Two Stars, Two Signals, No Planet
L. G. Bouma, J. N. Winn, G. R. Ricker +13
PTFO 8-8695 (CVSO 30) is a star in the 7-10 million year old Orion-OB1a cluster that shows brightness dips that resemble planetary transits. Although strong evidence against the pl…
Rotation and pulsation in Ap stars: first light results from TESS sectors 1 and 2
M. S. Cunha, V. Antoci, D. L. Holdsworth +36
We present the first results from the Transiting Exoplanet Survey Satellite (TESS) on the rotational and pulsational variability of magnetic chemically peculiar A-type stars. We an…