253 citations · 2.9k across the 51 of their papers we have counts for
16 papers · 1 filter
The active lives of stars: a complete description of rotation and XUV evolution of F, G, K, and M dwarfs
Colin P. Johnstone, Michael Bartel, Manuel Güdel
Aims. We study the evolution of rotation and high energy X-ray, extreme ultraviolet (EUV), and Ly-alpha emission for F, G, K, and M dwarfs, with masses between 0.1 and 1.2 Msun, an…
The solar wind from a stellar perspective: how do low-resolution data impact the determination of wind properties?
S. Boro Saikia, M. Jin, C. P. Johnstone +5
Alfvén-wave-driven 3D magnetohydrodynamic (MHD) models, which are increasingly used to predict stellar wind properties, contain unconstrained parameters and rely on low-resolution…
Stellar activity and planetary atmosphere evolution in tight binary star systems
C. P. Johnstone, E. Pilat-Lohinger, T. Lüftinger +2
Context. In tight binary star systems, tidal interactions can significantly influence the rotational and orbital evolution of both stars, and therefore their activity evolution. Th…
Slingshot prominence evolution for a solar-like star
Carolina Villarreal D'Angelo, Moira Jardine, Colin P. Johnstone +1
Although the present-day Sun rotates too slowly to exhibit centrifugally-supported 'slingshot prominences', at some time during its past it may have formed these clouds of cool gas…
Identifying the "true" radius of the hot sub-Neptune CoRoT-24b by mass loss modelling
H. Lammer, N. V. Erkaev, L. Fossati +8
For the hot exoplanets CoRoT-24b and CoRoT-24c, observations have provided transit radii R of 3.70.4 R and 4.90.5 R, and masses of 5.…
Stellar magnetic activity and their influence on the habitability of exoplanets
T. Lüftinger, M. Güdel, C. P. Johnstone
Stellar magnetism, explorable via polarimetry, is a crucial driver of activity, ionization, photodissociation, chemistry and winds in stellar environments. Thus it has an important…
Short-period stellar activity cycles with Kepler photometry
Oleksiy V. Arkhypov, Maxim L. Khodachenko, Helmut Lammer +3
We study the short-periodic component of stellar activity with a cycle periods Pcyc up to 1000 days using the Kepler mission photometry of fast-rotating (rotational periods from 1…
The Coronal Temperatures of Low-Mass Main-Sequence Stars
Colin P. Johnstone, Manuel Güdel
Aims. We study the X-ray emission of low-mass main-sequence stars to derive a reliable general scaling law between coronal temperature and the level of X-ray activity. Methods. We…
The Extreme Ultraviolet and X-Ray Sun in Time: High-Energy Evolutionary Tracks of a Solar-Like Star
Lin Tu, Colin P. Johnstone, Manuel Güdel +1
Aims. We aim to describe the pre-main sequence and main-sequence evolution of X-ray and extreme-ultaviolet radiation of a solar mass star based on its rotational evolution starting…
Stellar Winds on the Main-Sequence I: Wind Model
C. P. Johnstone, M. Güdel, T. Lüftinger +2
Aims: We develop a method for estimating the properties of stellar winds for low-mass main-sequence stars between masses of 0.4 and 1.1 solar masses at a range of distances from th…
Stellar Winds on the Main-Sequence II: the Evolution of Rotation and Winds
C. P. Johnstone, M. Güdel, I. Brott +1
Aims: We study the evolution of stellar rotation and wind properties for low-mass main-sequence stars. Our aim is to use rotational evolution models to constrain the mass loss rate…
Colliding Winds in Low-Mass Binary Star Systems: wind interactions and implications for habitable planets
C. P. Johnstone, A. Zhilkin, E. Pilat-Lohinger +3
Context. In binary star systems, the winds from the two components impact each other, leading to strong shocks and regions of enhanced density and temperature. Potentially habitabl…
Constraining Stellar Winds of Young Sun-like Stars
Colin P. Johnstone, Theresa Lüftinger, Manuel Güdel +1
As part of the project Pathways to Habitability (http://path.univie.ac.at/), we study the properties of the stellar winds of low-mass and Sun-like stars, and their influences on th…
Splinter Session "Solar and Stellar Flares"
L. Fletcher, H. S. Hudson, G. Cauzzi +8
This summary reports on papers presented at the Cool Stars-16 meeting in the splinter session "Solar and Stellar flares." Although many topics were discussed, the main themes were…
The contribution of starspots to coronal structure
Doris Arzoumanian, Moira Jardine, Jean-François Donati +2
Significant progress has been made recently in our understanding of the structure of stellar magnetic fields, thanks to advances in detection methods such as Zeeman-Doppler Imaging…
Modelling stellar coronae from surface magnetograms: the role of missing magnetic flux
Colin Johnstone, Moira Jardine, Duncan Mackay
Recent advances in spectropolarimetry have allowed the reconstruction of stellar coronal magnetic fields. This uses Zeeman-Doppler magnetograms of the surface magnetic field as a l…