Related papers: Close-by planets and flares in their host stars
Flares we observe on stars in white light, UV or soft X-rays are probably harbingers of coronal mass ejections (CMEs). If we use the Sun as a guide, large stellar flares will dissipate two orders of magnitude less X-ray radiative energy…
A new mechanism for the internal heating of ultra-short-period planets is proposed based on the gravitational perturbation by a non-axisymmetric quadrupole moment of their host stars. Such a quadrupole is due to the magnetic flux tubes in…
Young low-mass stars are characterized by ejection of collimated outflows and by circumstellar disks which they interact with through accretion of mass. The accretion builds up the star to its final mass and is also believed to power the…
Using the H$\alpha$ data from the New Vacuum Solar Telescope (NVST) at the Fuxian Solar Observatory together with multi-wavelength images and magnetograms obtained by Solar Dynamics Observatory (SDO), we study the detailed process of three…
Non-potential magnetic energy promptly released in solar flares is converted to other forms of energy. This may include nonthermal energy of flare-accelerated particles, thermal energy of heated flaring plasma, and kinetic energy of…
At least 10-15% of nearby sun-like stars have known Jupiter-mass planets. In contrast, very few planets are found in mature open and globular clusters such as the Hyades and 47 Tuc. We explore here the possibility that this dichotomy is due…
Solar and stellar flares are powerful events which produce intense radiation across the electromagnetic spectrum. Multiwavelength observations are highly important for understanding the nature of flares, because different flare-related…
It remains an open question how magnetic energy is rapidly released in the solar corona so as to create solar explosions such as solar flares and coronal mass ejections (CMEs). Recent studies have confirmed that a system consisting of a…
The X-rays and Extreme Ultraviolet (XUV) emission from M stars can drive the atmospheric escape on planets orbiting them. M stars are also known for their frequent emission of stellar flares, which will increase the high-energy flux…
The rotation period of some planet-hosting stars appears to be in close commensurability with the orbital period of their close-by planets. A model is proposed to interpret such a phenomenon based on the excitation of resonant oscillations…
Stellar flares with ${10^2-10^7}$ times more energy than the largest solar flare have been detected from 9 normal F and G main sequence stars (Schaefer, King & Deliyannis 1999). These superflares have durations of hours to days and are…
Both stars and planets can lose mass through an expansive wind outflow, often constrained or channeled by magnetic fields that form a surrounding magnetosphere. The very strong winds of massive stars are understood to be driven by…
We use three dimensional magnetohydrodynamic simulations to study the structure of the boundary layer between an accretion disc and a non-rotating, unmagnetized star. Under the assumption that cooling is efficient, we obtain a narrow but…
The statistical characteristic of stellar flares at optical bands has received an extensive study, but it remains to be studied at soft X-ray bands, in particular for solar-type stars. Here, we present a statistical study of soft X-ray…
The search for radio emission from extra-solar planets has so far been unsuccessful. Much of the effort in modelling the predicted emission has been based on the analogy with the well-known emission from Jupiter. Unlike Jupiter, however,…
According to recent observations relative number of flare stars does not change very much from cool dwarfs to hot A stars. Flare energies are strongly correlated with stellar luminosity and radius. Whence it follows that the typical…
Instabilities in planetary systems can result in the ejection of planets from their host system, resulting in free-floating planets (FFPs). If this occurs in a star cluster, the FFP may remain bound to the star cluster for some time and…
In exoplanetary systems, the interaction between the central star and the planet can trigger Auroral Radio Emission (ARE), due to the Electron Cyclotron Maser mechanism. The high brightness temperature of this emission makes it visible at…
The great majority of exoplanets discovered so far are orbiting cool, low-mass stars whose properties are relatively similar to the Sun. However, the stellar magnetism of these stars can be significantly different from the solar one, both…
Stellar flares are short-duration ($<$ hours) bursts of radiation associated with surface magnetic reconnection events. Stellar magnetic activity generally decreases as a function of both age and Rossby number, $R_0$, a measure of the…