相关论文: Magnetic Structure of Rapidly Rotating FK Comae-Ty…

We perform a numerical simulation of the corona of the young, rapidly rotating K0 dwarf AB Doradus using a global MHD model. The model is driven by a surface map of the radial magnetic field constructed using Zeeman-Doppler Imaging. We find…

We investigate the change in stellar magnetic topology across the fully-convective boundary and its effects on coronal properties. We consider both the magnitude of the open flux that influences angular momentum loss in the stellar wind and…

Stellar coronae are believed to be the main birthplace of various stellar magnetic activities. However, the structures and properties of stellar coronae remain poorly understood. Using the Space Weather Modelling Framework with the…

Three-dimensional magnetic topology of solar flare plays a crucial role in understanding its explosive release of magnetic energy in the corona. However, such three-dimensional coronal magnetic field is still elusive in direct observation.…

We develop a theoretical model that explains the formation of hot coronae around strongly magnetized neutron stars -- magnetars. The starquakes of a magnetar shear its external magnetic field, which becomes non-potential and is threaded by…

We study the magnetic field and current structure associated with a coronal loop. Through this we investigate to what extent the assumptions of a force-free magnetic field break down and where they might be justified. We analyse a 3D MHD…

We re-analyse spectropolarimetric data of AB Dor taken in 1996 December using a surface imaging code that can model the magnetic field of the star as a non-potential current-carrying magnetic field. We find that a non-potential field needs…

Observations indicate that magnetic fields in rapidly rotating stars are very strong, on both small and large scales. What is the nature of the resulting corona? Here we seek to shed some light on this question. We use the results of an…

Observations of surface magnetic fields are now within reach for many stellar types thanks to the development of Zeeman-Doppler Imaging. These observations are extremely useful for constraining rotational evolution models of stars, as well…

The coronal structure of main sequence stars continues to puzzle us. While the solar corona is relatively well understood, it has become clear that even stars of the same mass as the Sun can display very non-solar coronal behaviour,…

We present the results of a detailed numerical simulation of the circumstellar environment around three exoplanet-hosting stars. A state-of-the-art global magnetohydrodynamic (MHD) model is considered, including Alfv\'en wave dissipation as…

The structure and dynamics of the solar corona is dominated by the magnetic field. In most areas in the corona magnetic forces are so dominant that all non-magnetic forces like plasma pressure gradient and gravity can be neglected in the…

The magnetic fields in the solar corona are generally neither force-free nor axisymmetric and have complex dynamics that are difficult to characterize. Here we simulate the topological evolution of solar coronal magnetic field lines (MFLs)…

We use three-dimensional magnetohydrodynamical (MHD) simulations to study the formation of a corona above an initially weakly magnetized, isothermal accretion disk. We also describe a modification to time-explicit numerical algorithms for…

Measurement of the coronal magnetic field is a crucial ingredient in understanding the nature of solar coronal phenomena at all scales. We employed STEREO/COR1 data obtained during a deep minimum of solar activity in February 2008…

The structure of the solar corona is dominated by the magnetic field because the magnetic pressure is about four orders of magnitude higher than the plasma pressure. Due to the high conductivity the emitting coronal plasma (visible e.g. in…

We study the steady-state structure of an accretion disc with a corona surrounding a central, rotating, magnetized star. We assume that the magneto-rotational instability is the dominant mechanism of angular momentum transport inside the…

We present in this Letter the first global comparison between traditional line-tied steady state magnetohydrodynamic models and a new, fully time-dependent thermodynamic magnetohydrodynamic simulation of the global corona. The maps are…

We carry out the first time-dependent numerical MagnetoHydroDynamic modeling of an extrasolar planetary system to study the interaction of the stellar magnetic field and wind with the planetary magnetosphere and outflow. We base our model…

Our understanding of the structure and dynamics of stellar coronae has changed dramatically with the availability of surface maps of both star spots and also magnetic field vectors. Magnetic field extrapolations from these surface maps…