Projects per year
Abstract
Context. Magnetohydrostatic (MHS) equilibria are often used to model astrophysical plasmas, for example, planetary magnetospheres or coronae of magnetized stars. However, finding realistic threedimensional solutions to the MHS equations is difficult, with only a few known analytical solutions and even finding numerical solution is far from easy.
Aims. We extend the results of a previous paper on threedimensional solutions of the MHS equations around rigidly rotating massive cylinders to the much more realistic case of rigidly rotating massive spheres. An obvious application is to model the closed field line regions of the coronae of rapidly rotating stars.
Methods. We used a number of simplifying assumptions to reduce the MHS equations to a single elliptic partial differential equation for a pseudopotential U, from which all physical quantities, such as the magnetic field, the plasma pressure, and the density, can be derived by differentiation. The most important assumptions made are stationarity in the corotating frame of reference, a particular form for the current density, and neglect of outflows.
Results. In this paper we demonstrate that standard methods can be used to find numerical solutions to the fundamental equation of the theory. We present three simple different cases of magnetic field boundary conditions on the surface of the central sphere, corresponding to an aligned dipole field, a nonaligned dipole field, and a displaced dipole field. Our results show that it should be possible in the future to use this method without dramatically increasing the demands on computational resources to improve upon potential field models of rotating magnetospheres and coronae.
Original language  English 

Article number  A75 
Number of pages  7 
Journal  Astronomy & Astrophysics 
Volume  520 
DOIs  
Publication status  Published  Oct 2010 
Keywords
 Magnetic fields
 Magnetohydrodynamics (MHD)
 Stars: magnetic field
 Stars: coronae
 Stars: activity
 Electriccurrent systems
 Solar minimum corona
 Magnetostatic atmospheres
 ABdoradus
 Magnetohydrodynamic equilibria
 Cylindrical geometry
 MHD equilibria
 Field lines
 M dwarfs
 Model
Fingerprint
Dive into the research topics of 'Threedimensional solutions of the magnetohydrostatic equations: rigidly rotating magnetized coronae in spherical geometry'. Together they form a unique fingerprint.Projects
 3 Finished

Solar & Magnetospheric Plasma Theory: Solar and Magnetospheric plasma theory
Hood, A. W., Neukirch, T. & Roberts, B.
Science & Technology Facilities Council
1/04/10 → 31/03/15
Project: Standard


Solar&Magnetospheric Plasma Theory PP/E1: Solar and Magnetospheric Plasma Theory
Neukirch, T., Hood, A. W., Parnell, C. E., Priest, E., Roberts, B. & Wright, A. N.
1/04/07 → 31/03/12
Project: Standard