Related papers: Stellar wind induced soft X-ray emission from clos…
We present the results of a spectral study of the soft X-ray emission (0.2-2.5 keV) from low-latitude (`disk') regions of Jupiter. The data were obtained during two observing campaigns with XMM-Newton in April and November 2003. While the…
Charge exchange (CX) is a semi-resonant recombination process that can lead to spectral line emission in the X-ray band. It occurs in nearly any environment where hot plasma and cold gas interact: in the solar system, in comets and…
The exact nature of eta Carinae is still an open issue. In this paper we assume a binary system to explain the strong X-ray emission, but we also take into account that, near periastron and because of the highly eccentric orbit, the wind…
We present the first three-dimensional simulations of the evolution of a microquasar jet inside the binary-star system. The aim is to study the interaction of these jets with the stellar wind from a massive companion and the possible…
Planets in close orbits around their host stars are subject to strong irradiation. High-energy irradiation, originating from the stellar corona and chromosphere, is mainly responsible for the evaporation of exoplanetary atmospheres. We have…
Galaxies with intense star formation often host multiphase, galaxy-scale winds powered by supernovae and fast stellar winds. These are strong enough to disrupt the star-forming interstellar medium, and they chemically enrich the surrounding…
We present 3D MHD simulations of the wind-wind interactions between a solar type star and a short period hot Jupiter exoplanet. This is the first such simulation in which the stellar surface evolution is studied in detail. In our…
We present calculations of the auroral radio powers expected from exoplanets with magnetospheres driven by an Earth-like magnetospheric interaction with the solar wind. Specifically, we compute the twin cell-vortical ionospheric flows,…
High-resolution X-ray spectra of high-mass stars and low-mass T-Tauri stars obtained during the first year of the Chandra mission are providing important clues about the mechanisms which produce X-rays on very young stars. For zeta Puppis…
Hot gas dominates the emission in X-ray luminous early-type galaxies, but in relatively X-ray faint systems, integrated X-ray emission from discrete stellar-like sources is thought to be considerable, although the amount of the contribution…
Stellar activity can reveal itself in the form of radiation (eg, enhanced X-ray coronal emission, flares) and particles (eg, winds, coronal mass ejections). Together, these phenomena shape the space weather around (exo)planets. As stars…
We study the interactions between the stellar wind plasma flow of a typical M star, such as GJ 436, and hydrogen-rich upper atmospheres of an Earth-like planet and a "super-Earth" with the radius of 2 R_Earth and a mass of 10 M_Earth,…
Planets in close-in orbit interact with the magnetized wind of their hosting star. This magnetic interaction was proposed to be a source for enhanced emissions in the chromosphere of the star, and to participate in setting the migration…
The atmospheric circulation in the upper atmosphere of hot Jupiter planets is strongly influenced by the incoming stellar radiation. In this work we explore the results from a 3D atmospheric model and revisit the main processes driving the…
Planetary mass loss is governed by several physical mechanisms, including photoionisation that may impact the evolution of the atmosphere. Stellar radiation energy deposited as heat depends strongly on the energy of the primary electrons…
Galactic winds shape the stellar, gas, and metal content of galaxies. To quantify their impact, we must understand their physics. We review potential wind-driving mechanisms and observed wind properties, with a focus on the warm ionized and…
We analyze new high-resolution Chandra X-ray images of the Wolf-Rayet binary system WR147. This system contains a WN8 star with an early-type companion located 0.6'' to its north, and is the only known early-type binary with a separation on…
The X-ray emission from a simulated massive stellar cluster is investigated. The emission is calculated from a 3D hydrodynamical model which incorporates the mechanical feedback from the stellar winds of 3 O-stars embedded in a giant…
The Chandra X-ray Observatory has detected relatively hard X-ray emission from the central stars of several planetary nebulae (PNe). A subset have no known late-type companions, making it very difficult to isolate which of several competing…
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…