Related papers: The Hall effect in star formation
High-Velocity Clouds (HVCs) are believed to be an important source of gas accretion for star formation in the Milky Way. Earlier numerical studies have found that the Galactic magnetic field and radiative cooling strongly affects accretion.…
Non-ideal magnetohydrodynamics (MHD) is the dominant process. We investigate the effect of magnetic fields (ideal and non-ideal) and turbulence (sub- and transsonic) on the formation of circumstellar discs that form nearly simultaneously…
The role of non-ideal magnetohydrodynamics has been proven critical during the formation of the protoplanetary disk, particularly in regulating its size. We provide a simple model to predict the disk size under the interplay among the…
We present the results of eighteen magnetohydrodynamical calculations of the collapse of a molecular cloud core to form a protostar. Some calculations include radiative transfer in the flux-limited diffusion approximation while others…
This paper presents the results of the analysis of 3D simulations of solar magneto-convection that include the joint action of the ambipolar diffusion and the Hall effect. Three simulation-runs are compared: one including both ambipolar…
Protostars are born in magnetized environments. As a consequence, the formation of protostellar disks can be suppressed by the magnetic field efficiently removing angular momentum of the infalling material. Non-ideal MHD effects are…
Despite the ever growing observational evidence for the existence of the large scale magnetic fields, their origin and the evolution are not fully understood. If the magnetic fields are of primordial origin, they result in the generation of…
We investigate the formation and evolution of a first core, protostar, and circumstellar disc with a three-dimensional non-ideal (including both Ohmic and ambipolar diffusion) radiation magnetohydrodynamics simulation. We found that the…
We present results from the first radiation non-ideal magnetohydrodynamics (MHD) simulations of low-mass star cluster formation that resolve the fragmentation process down to the opacity limit. We model 50~M$_\odot$ turbulent clouds…
Collapse calculations indicate that the hot newly born protoneutron stars (PNS) rotate differentially so that strong toroidal magnetic field components should exist in the outer crust where also the Hall effect appears to be important when…
Observations indicate that dense molecular filamentary clouds are sites of star formation. The filament width determines the most unstable scale for self-gravitational fragmentation and influences the stellar mass. Therefore, constraining…
Understanding the star formation process is central to much of modern astrophysics. For several decades it has been thought that stellar birth is primarily controlled by the interplay between gravity and magnetostatic support, modulated by…
We consider formation of accretion disks from a realistically turbulent molecular gas using 3D MHD simulations. In particular, we analyze the effect of the fast turbulent reconnection described by the Lazarian & Vishniac (1999) model for…
Stellar feedback in the form of radiation pressure and magnetically-driven collimated outflows may limit the maximum mass that a star can achieve and affect the star-formation efficiency of massive pre-stellar cores. Here we present a…
If the angular momentum of the molecular cloud core were conserved during the star formation process, a new-born star would rotate much faster than its fission speed. This constitutes the angular momentum problem of new-born stars. In this…
Misalignment between rotation and magnetic field has been suggested to be one type of physical mechanisms which can easen the effects of magnetic braking during collapse of cloud cores leading to formation of protostellar disks. However,…
The effects of Hall electromotive forces (HEMFs) on the linear stability of protostellar disks are examined. Earlier work on this topic focused on axial field and perturbation wavenumbers. Here we treat the problem more generally. Both…
We employ the first fully three-dimensional simulation to study the role of magnetic fields and ion-neutral friction in regulating gravitationally-driven fragmentation of molecular clouds. The cores in an initially subcritical cloud develop…
The question whether magnetic fields play an important role in the processes of molecular cloud and star formation has been debated for decades. Recent observations have revealed a simple picture that may help illuminate these questions:…
Magnetic fields are believed to play an important role in controlling the stability and contraction of dense condensations of gas and dust leading to the formation of stars and planetary systems. In the present study, the magnetic field of…