相关论文: Atmospheric escape by magnetically driven wind fro…
Many of the planets discovered by the Kepler satellite are close orbiting Super-Earths or Mini-Neptunes. Such objects exhibit a wide spread of densities for similar masses. One possible explanation for this density spread is giant…
Observations of periodic stellar activity near the transit phase of a close-in exoplanet provide evidence of star-planet magnetic interactions (SPMI), similar to the magnetic coupling between Jupiter and its moons. Comparing the power…
Outflowing winds of multiphase plasma have been proposed to regulate the buildup of galaxies, but key aspects of these outflows have not been probed with observations. Using ultraviolet absorption spectroscopy, we show that "warm-hot"…
Computing the flow from externally FUV irradiated protoplanetary discs requires solving complicated and expensive photodissociation physics iteratively in conjunction with hydrodynamics. Previous studies have therefore been limited to 1D…
Evidence of star-planet interactions in the form of planet-modulated chromospheric emission has been noted for a number of hot Jupiters. Magnetic star-planet interactions involve the release of energy stored in the stellar and planetary…
Upper atmospheres of Hot Jupiters are subject to extreme radiation conditions that can result in rapid atmospheric escape. The composition and structure of the upper atmospheres of these planets are affected by the high-energy spectrum of…
Massive stars have strong stellar winds that direct their evolution through the upper Hertzsprung-Russell diagram and determine the black hole mass function. Secondly, wind strength dictates the atmospheric structure that sets the ionising…
Systems of close-in super-Earths display striking diversity in planetary bulk density and composition. Giant impacts are expected to play a role in the formation of many of these worlds. Previous works, focused on the mechanical shock…
Atmospheric escape is an important process that controls the long-term evolution of close-in planets. We perform radiation hydrodynamics simulations of photo-evaporation of exoplanets' atmospheres to study the effect of photoelectric…
Knowledge of both the mass and radius of an exoplanet allows us to estimate its mean density, and therefore its composition. Exoplanets seem to fill a very large parameter space in terms of mass and composition, and unlike the…
In this Letter, we make use of sophisticated 3D numerical simulations to assess the extent of atmospheric ion and photochemical losses from Mars over time. We demonstrate that the atmospheric ion escape rates were significantly higher (by…
Past studies have revealed the dependency of the disc parameters (mass, radius, viscosity, grain fragmentation velocity, dust-to-gas ratio) on the formation of giant planets, where more massive discs seem beneficial for giant planet…
Mass and radius of planets transiting their host stars are provided by radial velocity and photometric observations. Structural models of solid exoplanet interiors are then constructed by using equations of state for the radial density…
We examine the effects of the engulfment of planets by giant stars on the evolution of late-type stars. We show that the rate at which dynamo-generated magnetic energy is being released exceeds 10% of the wind kinetic energy when the…
We carry out an extended analytic study of how the tilt and faster-than-radial expansion from a magnetic field affect the mass flux and flow speed of a line-driven stellar wind. A key motivation is to reconcile results of numerical MHD…
Planetary migration is essential to explain the observed mass-period relation for exoplanets. Without some stopping mechanism, the tidal, resonant interaction between planets and their gaseous disc generally causes the planets to migrate…
Barred galaxies are known to possess magnetic fields that may affect the properties of bar substructures such as dust lanes and nuclear rings. We use two-dimensional high-resolution magnetohydrodynamic (MHD) simulations to investigate the…
Winds are commonly observed in luminous active galactic nuclei (AGNs). A plausible model of those winds is magnetohydrodynamic (MHD) disc winds. In the case of disc winds from a thin accretion disc, isothermal or adiabatic assumption is…
The cumulative effect of the magnetized stellar winds on exoplanets dominates over other forms of star-planet interactions. When combined with photoevaporation, these winds will lead to atmospheric erosion. This is directly connected with…
The anomalously large radii of strongly irradiated exoplanets have remained a major puzzle in astronomy. Based on a 2D steady state atmospheric circulation model, the validity of which is assessed by comparison to 3D calculations, we reveal…