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相关论文: Grain Dynamics In Magnetized Interstellar Gas

200 篇论文

We present high resolution ($1024^3$) simulations of super-/hyper-sonic isothermal hydrodynamic turbulence inside an interstellar molecular cloud (resolving scales of typically 20 -- 100 AU), including a multi-disperse population of dust…

星系天体物理 · 物理学 2018-12-19 Lars Mattsson , Akshay Bhatnagar , Fred A. Gent , Beatriz Villarroel

We investigate the combined effect of solar wind, Poynting-Robertson drag, and the frozen-in interplanetary magnetic field on the motion of charged dust grains in our solar system. For this reason we derive a secular theory of motion by the…

地球与行星天体物理 · 物理学 2016-08-26 Christoph Lhotka , Philippe Bourdin , Yasuhito Narita

Thermal fluctuations in the magnetization of interstellar grains will produce magnetic dipole emission at frequencies below ~100 GHz. We show how to calculate absorption and emission from small particles composed of magnetic materials. The…

天体物理学 · 物理学 2009-10-30 B. T. Draine , A. Lazarian

Given the important role turbulence plays in the settling and growth of dust grains in protoplanetary disks, it is crucial that we determine whether these disks are turbulent and to what extent. Protoplanetary disks are weakly ionized near…

Grains exposed to anisotropic radiation fields are subjected to forces due to the asymmetric photon-stimulated ejection of particles. These forces act in addition to the ``radiation pressure'' due to absorption and scattering. Here we model…

天体物理学 · 物理学 2009-10-31 Joseph C. Weingartner , B. T. Draine

In the interstellar medium of the Milky Way, certain elements -- e.g., Mg, Si, Al, Ca, Ti, Fe -- reside predominantly in interstellar dust grains. These grains absorb, scatter, and emit electromagnetic radiation, heat the interstellar…

天体物理学 · 物理学 2007-05-23 B. T. Draine

We investigate the dynamics of interstellar dust particles in moderately high resolution ($512^3$ grid points) simulations of forced compressible transonic turbulence including self-gravity of the gas. Turbulence is induced by stochastic…

星系天体物理 · 物理学 2021-12-07 Lars Mattsson , Robert Hedvall

Dust grains drift through the interstellar medium (ISM) and are aligned with the magnetic field. Here we study the effect of grain alignment and grain motion on grain growth in molecular clouds (MCs). We first discuss the characteristic…

星系天体物理 · 物理学 2022-04-06 Thiem Hoang

We study the drag force on dust grains moving at relativistic velocities through interstellar gas and explore its application. First, we derive a new analytical formula of the drag force at high energies and find that it is significantly…

星系天体物理 · 物理学 2017-10-04 Thiem Hoang

The degree to which interstellar grains align with respect to the interstellar magnetic field depends on disaligning as well as aligning mechanisms. For decades, it was assumed that disalignment was due primarily to the random angular…

星系天体物理 · 物理学 2015-05-13 Margaret E. Jordan , Joseph C. Weingartner

This study is motivated by recent observations on the ubiquitous interstellar density filaments and guided by the modern theory of magnetohydrodynamic (MHD) turbulence. The interstellar turbulence shapes the observed density structure. The…

星系天体物理 · 物理学 2018-02-06 Siyao Xu , Alex Lazarian

We develop a 3D dynamical model of dust outflows from galactic discs. The outflows are initiated by multiple SN explosions in a magnetized interstellar medium (ISM) with a gravitationally stratified density distribution. Dust grains are…

星系天体物理 · 物理学 2014-03-28 S. A. Khoperskov , Yu. A. Shchekinov

The interaction of dust grains originating from the local interstellar cloud with the environment inside the heliosphere is investigated. As a consequence of this interaction the spatial distribution of interstellar dust grains changes with…

天体物理学 · 物理学 2015-06-24 M. Landgraf

Aligned grains present a foreground for cosmic microwave emission studies. We review basic physical processes involved in grain alignment and discuss the niches for different alignment mechanisms. We show that mechanisms which were favored…

天体物理学 · 物理学 2007-05-23 A. Lazarian , Jungyeon Cho

This study is motivated by recent observations on ubiquitous interstellar density filaments and guided by modern theories of compressible magnetohydrodynamic (MHD) turbulence. The interstellar turbulence shapes the observed density…

星系天体物理 · 物理学 2019-08-07 Siyao Xu , Suoqing Ji , A. Lazarian

We discuss the forces on grains exposed to anisotropic radiation fields, including the usual ``radiation pressure'' force and also recoil forces due to photoemitted electrons, photodesorbed hydrogen atoms, and hydrogen molecules which form…

天体物理学 · 物理学 2007-05-23 Joseph C. Weingartner , Bruce T. Draine

Measurements by dust detectors on interplanetary spacecraft appear to indicate a substantial flux of interstellar particles with masses exceeding 10^{-12}gram. The reported abundance of these massive grains cannot be typical of interstellar…

天体物理学 · 物理学 2009-11-13 B. T. Draine

We study the motion of dust grains into the Intergalactic Medium (IGM) around redshift z=3, to test the hypothesis that grains can efficiently pollute the gas with metals through sputtering. We use the results available in the literature…

天体物理学 · 物理学 2009-11-10 Simone Bianchi , Andrea Ferrara

We study the behavior of large dust grains in turbulent molecular clouds (MCs). In primarily neutral regions, dust grains move as aerodynamic particles, not necessarily with the gas. We therefore directly simulate, for the first time, the…

星系天体物理 · 物理学 2016-11-09 Philip F. Hopkins , Hyunseok Lee

(abridged) We aim to predict the most important parameters for grain-grain collision outcomes for models of interstellar grain population evolution on astrophysical scales: the threshold velocity above which colliding grains shatter, the…