English
Related papers

Related papers: Formation of Fluctuations in the Molecular Slab vi…

200 papers

Although thermal pressure is unimportant dynamically in most molecular gas, the temperature is an important diagnostic of dynamical processes and physical conditions. This is the first of two papers on thermal equilibrium in molecular…

Astrophysics · Physics 2009-10-31 Paolo Padoan , ; Ellen Zweibel , ; AAke Nordlund

We present an investigation on effect of the ion-neutral (or ambipolar) diffusion heating rate on thermal phases of a molecular cloud. We use the modeling of ambipolar diffusion with two-fluid smoothed particle hydrodynamics, as discussed…

Astrophysics · Physics 2008-04-29 M. Nejad-Asghar , D. Molteni

The heating of the ion-neutral (or ambipolar) diffusion may affect the thermal phases of the molecular clouds. We present an investigation on the effect of this heating mechanism in the thermal instability of the molecular clouds. A weakly…

Astrophysics · Physics 2009-11-13 Mohsen Nejad-Asghar , Diego Molteni

Thermal instability is one of the most important processes in the formation of clumpy substructure in magnetic molecular clouds. On the other hand, ambipolar diffusion, or ion-neutral friction, has long been thought to be an important…

Astrophysics · Physics 2009-11-10 Mohsen Nejad-Asghar , Jamshid Ghanbari

Observational evidence in space and astrophysical plasmas with long collisional mean free path suggests that more massive charged particles may be preferentially heated. One possible mechanism for this is the turbulent cascade of energy…

Plasma Physics · Physics 2018-01-15 M. Barnes , P. Abiuso , W. Dorland

A systematic study of the linear thermal instability of a self-gravitating magnetic molecular cloud is carried out for the case when the unperturbed background is subject to local expansion or contraction. We consider the ambipolar…

Astrophysics · Physics 2009-11-11 Mohsen Nejad-Asghar , Jamshid Ghanbari

We study magnetothermal instability in the ionized plasmas including the effects of Ohmic, ambipolar and Hall diffusion. Magnetic field in the single fluid approximation does not allow transverse thermal condensations, however, non-ideal…

Solar and Stellar Astrophysics · Physics 2014-11-20 Mohsen Shadmehri , Mohsen Nejad-Asghar , Alireza Khesali

We revisit the modeling of ion-neutral (or ambipolar) diffusion with two fluid smoothed particle hydrodynamics, as discussed by Hosking & Whitworth. Some parts of the technique are optimized to testify the pioneer works on behavior of the…

Astrophysics · Physics 2008-04-13 M. Nejad-Asghar , D. Molteni

Evidence of small-scale condensations in the magnetic molecular clouds has been accumulating over the past decades through radio and optical/ultraviolet observations. The origin and shape of these small-scale condensations is a disputable…

Astrophysics · Physics 2007-05-23 Mohsen Nejad-Asghar , Jamshid Ghanbari

The drift instabilities driven by the slab ion temperature gradient (ITG) in Kappa-distributed plasmas are investigated by the kinetic method. The linear dispersion relation is given in an integral representation involving only the standard…

Plasma Physics · Physics 2024-09-05 Ran Guo

I discuss the role of self-gravity and radiative heating and cooling in shaping the nature of the turbulence in the interstellar medium (ISM) of our galaxy. The heating and cooling cause it to be highly compressible, and, in some regimes of…

Astrophysics of Galaxies · Physics 2012-02-22 Enrique Vazquez-Semadeni

(Shortened) Thermal instability of partially ionized plasma is investigated by linear perturbation analysis. According to the previous studies under the one fluid approach, the thermal instability is suppressed due to the magnetic pressure.…

Astrophysics · Physics 2014-11-18 Tsubasa Fukue , Hideyuki Kamaya

The ambipolar diffusion approximation is used to model partially ionised plasma dynamics in a single fluid setting. To correctly apply the commonly used version of ambipolar diffusion, a set of criteria should be satisfied including the…

Solar and Stellar Astrophysics · Physics 2024-03-26 Andrew Hillier

Self-gravity becomes competitive as an angular momentum transport process in accretion discs at large radii, where the temperature is low enough that external irradiation likely contributes to the thermal balance. Irradiation is known to…

Solar and Stellar Astrophysics · Physics 2015-05-30 W. K. M. Rice , P. J. Armitage , G. R. Mamatsashvili , G. Lodato , C. J. Clarke

The interstellar magnetic field strength and gas density are observed to be correlated, but there is a large dispersion in this relation. In particular, the magnetic field is often observed to be weaker than expected. It is usually assumed…

Astrophysics · Physics 2009-11-06 Ellen G. Zweibel

In collisionless astrophysical plasmas, turbulence mediates the partitioning of free energy among cascade channels and its dissipation into ion and electron heat. The resulting ion heating is often anisotropic, with ions observed to be…

Solar and Stellar Astrophysics · Physics 2025-12-04 Zade Johnston , Jonathan Squire

We investigate the dynamical condensation process in a magnetized thermally bistable medium. We perform one-dimensional two fluid numerical simulations that describe the neutral and ionized components in the interstellar medium with purely…

Astrophysics · Physics 2009-11-11 Tsuyoshi Inoue , Shu-ichiro Inutsuka , Hiroshi Koyama

This chapter reviews the nature of turbulence in the Galactic interstellar medium (ISM) and its connections to the star formation (SF) process. The ISM is turbulent, magnetized, self-gravitating, and is subject to heating and cooling…

Astrophysics of Galaxies · Physics 2017-03-15 Enrique Vazquez-Semadeni

In every turbulent flow with non-zero viscosity, heat is generated by viscous friction. This heat is then mixed by the velocity field. We consider how heat fluctuations generated this way are injected and distributed over length scales in…

Fluid Dynamics · Physics 2015-06-18 Wouter Bos

An interesting feature of the Davies-Unruh effect is that an uniformly accelerated observer sees an isotropic thermal spectrum of particles even though there is a preferred direction in this context, determined by the direction of the…

General Relativity and Quantum Cosmology · Physics 2012-11-29 Sanved Kolekar , T. Padmanabhan
‹ Prev 1 2 3 10 Next ›