Related papers: Interaction between Granulation and Small-Scale Ma…
We review the role that magnetic field may have on the formation and evolution of molecular clouds. After a brief presentation and main assumptions leading to ideal MHD equations, their most important correction, namely the ion-neutral…
The Sun's magnetic field is structured over a range of scales that span approximately seven orders of magnitudes, four of which lie beyond the resolving power of current telescopes. Here we have used a Hinode SOT/SP deep mode data set for…
We investigate the formation of circumstellar disks and outflows subsequent to the collapse of molecular cloud cores with the magnetic field and turbulence. Numerical simulations are performed by using an adaptive mesh refinement to follow…
In this work, we study and quantify properties of strong-field small-scale convection and compare observed properties with those predicted by numerical simulations. We analyze spectropolarimetric 630.25 nm data from a unipolar ephemeral…
Aims. We study the emergence of a non-twisted flux tube from the solar interior into the solar atmosphere. We investigate whether the length of the buoyant part of the flux tube (i.e. {\lambda}) affects the emergence of the field and the…
Solar activity is controlled by the magnetic field, which also causes the variability of the solar irradiance that in turn is thought to influence the climate on Earth. The magnetic field manifests itself in the form of structures of…
We consider that no mean magnetic field exists during this epoch, but that there is a mean magnetic energy associated with large-scale magnetic inhomogeneities. We study the evolution of these inhomogeneities and their influence on the…
Hydrodynamic simulations of granular convection predict the existence of supersonic flows covering ~3-4% of the solar surface at any time, but these flows have not been detected unambigously as yet. Using data from the spectropolarimeter…
Spectropolarimetric observations show that many low-mass stars possess large-scale poloidal magnetic fields with considerable dipole component, which in some cases exhibit temporal dynamics - cycles or reversals. Although it is widely…
Observations of stable mainly dipolar magnetic fields at the surface of ~7% of single hot stars indicate that these fields are of fossil origin, i.e. they descend from the seed field in the molecular clouds from which the stars were formed.…
Random motions can occur in the intergalactic gas of galaxy clusters at all stages of their evolution. Depending on the poorly known value of the Reynolds number, these motions can or cannot become turbulent, but in any case they can…
The origin of large scale magnetic fields in the Universe is widely thought to be from early Universe processes, like inflation or phase transitions. These magnetic fields evolve via magnetohydrodynamic processes until the epoch of…
We have experimentally investigated field induced aggregation of nonmagnetic particles confined in a magnetic fluid layer when rotating magnetic fields were applied. After application of a magnetic field rotating in the plane of the fluid…
In paper I, we obtained an equation for the evolution of density inhomogeneities in a radiation dominated universe when they are affected by magnetic fields. In this second paper we apply this equation to the case in which the subjacent…
(abridged) Context: The mechanisms that cause the formation of sunspots are still unclear. Aims: We study the self-organisation of initially uniform sub-equipartition magnetic fields by highly stratified turbulent convection. Methods: We…
We report the discovery of isolated, small-scale emerging magnetic fields in a plage region with the Solar Optical Telescope aboard Hinode. Spectro-polarimetric observations were carried out with a cadence of 34 seconds for the plage region…
The advection of internetwork magnetic elements by supergranular convective flows is investigated using high spatial resolution, high cadence, and high signal-to-noise ratio Na I D1 magnetograms obtained with the Hinode satellite. The…
Recent observations suggest that magnetic flux cancellation may play a crucial role in heating the Sun's upper atmosphere (chromosphere, transition region, corona). Here, we intended to validate an analytic model for magnetic reconnection…
Context: The determination of the underlying mechanisms of the magnetic elements diffusion over the solar surface is still a challenge. Understanding the formation and evolution of the solar network (NE) is a challenge, because it provides…
The first galaxies form due to gravitational collapse of primordial halos. During this collapse, weak magnetic seed fields get amplified exponentially by the small-scale dynamo - a process converting kinetic energy from turbulence into…