Context. The presence of vortices in accretion discs has been debated for more than a
decade. Baroclinic instabilities might be a way to generate these vortices in the presence of …

We describe the implementation of the shearing box approximation for the study of the
dynamics of accretion disks in the Athena magnetohydrodynamic (MHD) code. Second …

Context. Possible effects of magnetic fields in core collapse supernovae rely on an efficient
amplification of the weak pre-collapse fields. It has been suggested that the magneto …

The magnetorotational instability (MRI) is a fundamental mechanism determining the
macroscopic dynamics of astrophysical accretion disks. In collisionless accretion flows …

Context. The existence of large-scale and long-lived 2D vortices in accretion discs has been
debated for more than a decade. They appear spontaneously in several 2D disc simulations …

Magnetorotational turbulence and magnetically driven disc winds are often considered as
separate processes. However, realistic astrophysical discs are expected to be subject to …

Context. Turbulence and angular momentum transport in accretion disks remains a topic of
debate. With the realization that dead zones are robust features of protoplanetary disks, the …

Context. Explicit numerical computations of hypersonic or super-fast differentially rotating
disks are subject to the time-step constraint imposed by the Courant condition, according to …

Context. MRI turbulence is a leading mechanism for the generation of an efficient turbulent
transport of angular momentum in an accretion disk through a turbulent viscosity effect. It is …

Context. MHD turbulence is known to exist in shearing boxes with either zero or nonzero net
magnetic flux. However, the way turbulence survives in the zero-net-flux case is not …