Publications (11)
A single power law for the TRAPPIST-1 flare distribution across four orders of magnitude in energy
Valeriy Vasilyev, Alexander I. Shapiro, Nadiia Kostogryz +10
TRAPPIST-1 is an ultra-cool dwarf that flares frequently. These flares shape the surrounding planets' high-energy irradiation environments, with consequences for atmospheric chemis…
Understanding Sun-as-a-star variability of solar Balmer lines
Serena Criscuoli, Sergey Marchenko, Matthew DeLand +2
Precise, high-cadence, long-term records of stellar spectral variability at different temporal scales lead to better understanding of a wide variety of phenomena including stellar…
Reconstructing solar irradiance from historical Ca II K observations. I. Method and its validation
Theodosios Chatzistergos, Natalie A. Krivova, Ilaria Ermolli +5
Knowledge of solar irradiance variability is critical to Earth's climate models and understanding the solar influence on Earth's climate. Direct solar irradiance measurements are o…
Methodology to create a new Total Solar Irradiance record: Making a composite out of multiple data records
Thierry Dudok de Wit, Greg Kopp, Claus Fröhlich +1
Many observational records critically rely on our ability to merge different (and not necessarily overlapping) observations into a single composite. We provide a novel and fully-tr…
Irradiance Variations of the Sun and Sun-Like Stars -- Overview of Topical Collection
Greg Kopp, Alexander Shapiro
This topical collection summarizes recent advances in observing and modeling irradiance variations of the Sun and Sun-like stars, emphasizing the links between surface magnetic fie…
Decoding the Radial Velocity Signatures of Solar Faculae with 3D MHD Simulations
Florian Kröll, Sowmya Krishnamurthy, Alexander Shapiro +8
We model the solar radial velocity (RV) signal induced by faculae, the dominant contributor to RV variability in Sun-like stars. We use a representative case of a facular patch tra…