Related papers: Coronal influence on dynamos
This paper is the second in a series of studies working towards constructing a realistic, evolving, non-potential coronal model for the solar magnetic carpet. In the present study, the interaction of two magnetic elements is considered. Our…
Helioseismology shows that the regions occupied by convection and differential rotation inside the sun almost coincide. This supports the leading theoretical concept for the origin of differential rotation as a result of interaction between…
A hot corona is suggested to be above the standard thin disk. The anisotropy of hard X-ray emission in radio-quiet active galactic nuclei implies that the corona is not static and probably moves outwards like winds. We perform…
Coronal heating through the explosive release of magnetic energy remains an open problem in solar physics. Recent hydrodynamical models attempt an investigation by placing swarms of 'nanoflares' at random sites and times in modeled…
We perform a number of numerical simulations of the solar corona with the aim to understand how it responds to different conditions in the photosphere. By changing parameters which govern the motion of the plasma at the photosphere we study…
The coronal magnetic field directly or indirectly affects a majority of the phenomena studied in space physics. It provides energy for coronal heating, controls the release of coronal mass ejections (CMEs), and drives heliospheric and…
We report the results of three-dimensional numerical simulations of convection-driven dynamos in relatively thin rotating spherical shells that show a transition from an strong non-oscillatory dipolar magnetic field to a weaker regularly…
The level of solar magnetic activity, as exemplified by the number of sunspots and by energetic events in the corona, varies on a wide range of time scales. Most prominent is the 11-year solar cycle, which is significantly modulated on…
This review provides an introduction to the generation and evolution of the Sun's magnetic field, summarising both observational evidence and theoretical models. The eleven year solar cycle, which is well known from a variety of observed…
Convective turbulent motions in the solar interior, as well as the mean flows resulting from them, determine the evolution of the solar magnetic field. With the aim to get a better understanding of these flows we study anelastic rotating…
When magnetic field in the solar convection zone buoyantly rises to pierce the visible solar surface (photosphere), the atmosphere (corona) above this surface must respond in some way. One response of the coronal field to photospheric…
Increasing evidence is becoming available about not only the surface differential rotation of rapidly rotating cool stars but, in a small number of cases, also about temporal variations, which possibly are analogous to the solar torsional…
Helioseismology provides important constraints for the solar dynamo problem. However, the basic properties and even the depth of the dynamo process, which operates also in other stars, are unknown. Most of the dynamo models suggest that the…
We present a new global model of the solar corona, including the low corona, the transition region and the top of chromosphere. The realistic 3D magnetic field is simulated using the data from the photospheric magnetic field measurements.…
We quantify possible differences between turbulent dynamo action in the Sun and the dynamo action studied in idealized simulations. For this purpose we compare Fourier-space shell-to-shell energy transfer rates of three incrementally more…
Employing the standard solar interior model as input we construct a dynamically-consistent nonlinear dynamo model that takes into account the detailed description of the \Lambda- effect, turbulent pumping, magnetic helicity balance, and…
We demonstrate that a magneto-convection simulation incorporating essential physical processes governing solar surface convection exhibits turbulent small-scale dynamo action. By presenting a derivation of the energy balance equation and…
The most violent space weather events (eruptive solar flares and coronal mass ejections) are driven by the release of free magnetic energy stored in the solar corona. Energy can build up on timescales of hours to days, and then may be…
Planetary and stellar dynamos likely result from turbulent motions in magnetofluids with kinematic viscosities that are small compared to their magnetic diffusivities. Laboratory experiments are in progress to produce similar dynamos in…
The differential rotation of the solar corona for the period 1976-2004 was studied as a function of the distance from the center of the Sun. For this study, we developed a method using the coronal magnetic field as a tracer. The field in a…