相关论文: Magnetic tension and instabilities in the Orion A …
By comparing 3 constituents of Orion A (gas, protostars, and pre-main-sequence stars), both morhologically and kinematically, we derive the following. The gas surface density near the integral-shaped filament (ISF) is well represented by a…
We present simulations of collapsing filaments studying the impact of turbulence and magnetic field morphologies on their evolution and star formation properties. We vary the mass per unit length of the filaments as well as the orientation…
We examine the role of the gravitational instability in an isothermal, self-gravitating layer threaded by magnetic fields on the formation of filaments and dense cores. Using numerical simulation we follow the non-linear evolution of a…
Magnetic pressure has long been known to dominate over gas pressure in atomic and molecular regions of the interstellar medium. Here I review several recent observational studies of the relationships between the H^+, H^0 and H_2 regions in…
Filaments are a key step on the path that leads from molecular clouds to star formation. However, their characteristics are heavily debated, and the exact processes that lead to their formation and fragmentation into dense cores still…
We use numerical simulations of turbulent cluster-forming regions to study the nature of dense filamentary structures in star formation. Using four hydrodynamic and magnetohydrodynamic simulations chosen to match observations, we identify…
We suggest that the Orion A cloud is gravitationally collapsing on large scales, and is producing the Orion Nebula Cluster due to the focusing effects of gravity acting within a finite cloud geometry. In support of this suggestion, we show…
Observations of the Orion-A integral shaped filament (ISF) have shown indications of an oscillatory motion of the gas filament. This evidence is based on both the wave-like morphology of the filament as well as the kinematics of the gas and…
As well known, magnetic fields in space are distributed very inhomogeneously. Some-times field distributions have forms of filaments with high magnetic field values. As many ob-servations show, such a filamentation takes place in convective…
Angular momentum is one of the most important physical quantities that govern star formation. The initial angular momentum of a core may be responsible for its fragmentation and can have an influence on the size of the protoplanetary disk.…
The physical properties of the so-called Ostriker isothermal, non-rotating filament have been classically used as benchmark to interpret the stability of the filaments observed in nearby clouds. However, such static picture seems to…
We present three Orion simulations of star cluster formation in a 1000 Msun, turbulent molecular cloud clump, including the effects of radiative transfer, protostellar outflows, and magnetic fields. Our simulations all use self-consistent…
The Integral Shaped Filament (ISF) is the nearest molecular cloud with rapid star formation, including massive stars, and it is therefore a star-formation laboratory. We use Gaia parallaxes, to show that the distances to young Class II…
Magnetic fields are an important component of the interstellar medium (ISM) and exhibit strongly varying field strengths and a non-trivial correlation with the gas density. Its dynamical impact varies between individual regions of the ISM…
The question of the origin and evolution of magnetic fields in stars possessing a radiative envelope, like the A-type stars, is still regarded as a challenge for stellar physics. Those zones are likely to be differentially rotating, which…
Radio continuum observations allow to reveal the magnetic field structure in the disk and halo of nearby spiral galaxies, their magnetic field strength and vertical scale heights. The spiral galaxies studied so far show a similar magnetic…
Recent observations suggest a scenario in which filamentary structures in the ISM represent the first step towards clumps/cores and eventually star formation. The densest filaments would then fragment into prestellar cores owing to…
Magnetic fields permeate the Universe on all scales and play a key role during star formation. We study the evolution of magnetic fields around a massive metal-free (Population III) star at $z \sim 15$ during the growth of its HII region…
{Filaments are ubiquitous in the interstellar medium as recently emphasized by Herschel, yet their physical origin remains elusive} {It is therefore important to understand the physics of molecular clouds to investigate how filaments form…
We present the formation and eruption of a sigmoidal filament driven by rotating network magnetic fields (RNFs) near the center of the solar disk, which was observed by the one-meter aperture New Vacuum Solar Telescope (NVST) at Fuxian…