Related papers: Can we detect aurora in exoplanets orbiting M dwar…
After nearly three decades of discovery, many exoplanetary systems have been studied and characterized in detail with one important exception: exoplanet magnetism. Although many surveys sought to detect magnetospheric radio emissions from…
Context. Planets around stars in the solar neighbourhood will be prime targets for characterisation with upcoming large space- and ground-based facilities. Since large-scale exoplanet searches will not be feasible with such telescopes, it…
White dwarfs stars are known to be polluted by their active planetary systems, but little attention has been paid to the accretion of wind from low-mass companions. The capture of stellar or substellar wind by white dwarfs is one of few…
The only way to detect planets around stars at distances of several kpc is by (photometric or astrometric) microlensing observations. In this paper, we show that the capability of photometric microlensing extends to the detection of signals…
The James Webb Space Telescope (JWST) will open up the possibility of comprehensively measuring the emission spectra of rocky exoplanets orbiting M dwarfs to detect and characterize their atmospheres. In preparation for this opportunity, we…
[abridged] We carry out numerical simulations to gauge the Gaia potential for precision astrometry of exoplanets orbiting a sample of known dM stars within 30 pc from the Sun. (1) It will be possible to accurately determine orbits and…
M dwarfs are ideal targets for the search of Earth-size planets in the habitable zone using the radial velocity method, attracting the attention of many ongoing surveys. As a by-product of these surveys, new multiple stellar systems are…
Radiation belts are present in all large-scale Solar System planetary magnetospheres: Earth, Jupiter, Saturn, Uranus, and Neptune. These persistent equatorial zones of trapped high energy particles up to tens of MeV can produce bright radio…
The 2001 discovery of radio emission from ultra-cool dwarfs (UCDs), the very low-mass stars and brown dwarfs with spectral types of ~M7 and later, revealed that these objects can generate and dissipate powerful magnetic fields. Radio…
We present the serendipitous discovery of 8 distant ($>$ 50 pc) late M dwarfs with plausible associated radio emission at 144 MHz. The M dwarf nature of our sources has been confirmed with optical spectroscopy performed using HET/LRS2 and…
A number of O stars are suspected to have (weak) magnetic fields because of the observed cyclical variability in their UV wind-lines. However, direct detections of these magnetic fields with optical spectropolarimetry have proven to be very…
Correct estimates of stellar extreme ultraviolet (EUV; 100 - 1170 \AA) flux are important for studying the photochemistry and stability of exoplanet atmospheres, as EUV radiation ionizes hydrogen and contributes to the heating, expansion,…
Context: How planet properties depend on stellar mass is a key diagnostic of planetary formation mechanisms. Aims: This motivates planet searches around stars which are significantly more massive or less massive than the Sun, and in…
As stars evolve, they undergo significant changes in their physical properties, which can have a profound impact on the planets orbiting them. In particular, the mass lost through stellar wind may be partially accreted by orbiting planets.…
Exoplanets orbiting M dwarf stars are a prime target in the search for life in the Universe. M dwarf stars are active, with powerful flares that could adversely impact prospects for life, though there are counter-arguments. Here, we turn…
Proxima b is our nearest potentially rocky exoplanet and represents a formidable opportunity for exoplanet science and possibly astrobiology. With an angular separation of only 35~mas (or 0.05~AU) from its host star, Proxima b is however…
The space-weather conditions that result from stellar winds significantly impact the habitability of exoplanets. The conditions can be calculated from first principles if the necessary boundary conditions -- namely on the plasma density in…
Context. Radial velocity monitoring of very cool dwarfs such as late M- and hot L-dwarfs has become a promising tool to search for rocky planets as well as to follow-up planetary candidates around dwarfs found by transit surveys. These…
(Abridged) Searching for planets around stars with different masses probes the outcome of planetary formation for different initial conditions. This drives observations of a sample of 102 southern nearby M dwarfs, using a fraction of our…
The determination of extrasolar planet masses with the radial velocity (RV) technique requires spectroscopic Doppler information from the planet's host star, which varies with stellar brightness and temperature. We analyze Doppler…