English
Related papers

Related papers: Magnetically Aligned Velocity Anisotropy in the Ta…

200 papers

We present numerical simulations of electron magnetohydrodynamic (EMHD) and electron reduced MHD (ERMHD) turbulence. Comparing scaling relations, we find that both EMHD and ERMHD turbulence show similar spectra and anisotropy. We develop…

Earth and Planetary Astrophysics · Physics 2009-07-24 Jungyeon Cho , A. Lazarian

We extend previous studies of the physics of interstellar cloud collisions by beginning investigation of the role of magnetic fields through 2D magnetohydrodynamic (MHD) numerical simulations. We study head-on collisions between equal mass,…

Astrophysics · Physics 2009-10-30 Francesco Miniati , Dongsu Ryu , Andrea Ferrara , T. W. Jones

The scaling anisotropy is crucial to interpret the nonlinear interactions in solar wind turbulence. Previous observations provide diverse results and the structure function analyses are also reported to be an approach to investigate the…

Space Physics · Physics 2020-11-23 Honghong Wu , Chuanyi Tu , Xin Wang , Jiansen He , Liping Yang , Linghua Wang

Based on magnetohydrodynamic turbulence simulations, we generate synthetic synchrotron observations to explore the scaling slope of the underlying MHD turbulence. We propose the new $Q$-$U$ cross intensity $X$ and cross-correlation…

High Energy Astrophysical Phenomena · Physics 2023-07-05 Zhang Xue-Wen , Zhang Jian-Fu , Wang Ru-Yue , Xiang Fu-Yuan

The coupling state between ions and neutrals in the interstellar medium plays a key role in the dynamics of magnetohydrodynamic (MHD) turbulence, but is challenging to study numerically. In this work, we investigate the damping of MHD…

Astrophysics of Galaxies · Physics 2023-11-13 Yue Hu , Siyao Xu , Lev Arzamasskiy , James M. Stone , A. Lazarian

The Very Local Interstellar Medium (VLISM) contains clouds which consist of partially-ionized plasma. These clouds can be effectively diagnosed via high resolution optical and ultraviolet spectroscopy of the absorption lines they form in…

Astrophysics of Galaxies · Physics 2015-05-19 Steven R. Spangler , Allison H. Savage , Seth Redfield

We show that under very general conditions, cluster plasmas threaded by weak magnetic fields are subject to very fast growing plasma instabilities driven by the anisotropy of the plasma pressure (viscous stress) with respect to the local…

Astrophysics · Physics 2008-11-26 A. A. Schekochihin , S. C. Cowley , R. M. Kulsrud , G. W. Hammett , P. Sharma

We present a new method of constraining the mass and velocity anisotropy profiles of galaxy clusters from kinematic data. The method is based on a model of the phase space density which allows the anisotropy to vary with radius between two…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Radoslaw Wojtak , Ewa L. Lokas , Gary A. Mamon , Stefan Gottloeber

We numerically investigate the driving of MHD turbulence by gravitational contraction using simulations of an initially spherical, magnetically supercritical cloud core with initially transonic and trans-Alfv\'enic turbulence. We perform a…

Astrophysics of Galaxies · Physics 2024-03-04 Enrique Vázquez-Semadeni , Yue Hu , Siyao Xu , Rubén Guerrero-Gamboa , Alex Lazarian

The anisotropy of solar wind turbulence is a critical issue in understanding the physics of energy transfer between scales and energy conversion between fields and particles in the heliosphere. Using the measurement of \emph{Parker Solar…

We analyze the spatial anisotropy and the velocity anisotropy in a set of mock stellar halos from the Aquarius simulations. The spatial anisotropy in each mock stellar halo rises progressively with the increasing distance from the halo…

Astrophysics of Galaxies · Physics 2024-09-17 Amit Mondal , Biswajit Pandey

Young stars form in molecular cores, which are dense condensations within molecular clouds. We have searched for molecular cores traced by $^{13}$CO $J=1\to 0$ emission in the Taurus molecular cloud and studied their properties. Our data…

Astrophysics of Galaxies · Physics 2015-06-05 Lei Qian , Di Li , Paul Goldsmith

Trying to obtain a more complete picture of star forming regions in the Taurus Molecular Cloud, four newly discovered dense cores (L1521D, L1521F, L1524, L1507A) are identified and mapped through the ammonia (J,K)=(1,1) and (2,2) rotational…

Astrophysics · Physics 2007-05-23 C. Codella , R. Welser , C. Henkel , P. J. Benson , P. C. Myers

An optically and geometrically thick torus obscures the central engine of Active Galactic Nuclei (AGN) from some lines of sight. From a magnetohydrodynamical framework, the torus can be considered to be a particular region of clouds…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-21 E. Lopez-Rodriguez , C. Packham , S. Young , M. Elitzur , N. A. Levenson , R. E. Mason , C. Ramos Almeida , A. Alonso-Herrero , T. J. Jones , E. Perlman

We describe a morphological imprint of magnetization found when considering the relative orientation of the magnetic field direction with respect to the density structures in simulated turbulent molecular clouds. This imprint was found…

Astrophysics of Galaxies · Physics 2013-08-27 J. D. Soler , P. Hennebelle , P. G. Martin , M. A. Miville-Deschênes , C. B. Netterfield , L. M. Fissel

We analyze 3D numerical simulations of driven incompressible magnetohydrodynamic (MHD) turbulence in a periodic box threaded by a moderately strong external magnetic field. We sum over nonlinear interactions within Fourier wavebands and…

Astrophysics · Physics 2011-05-10 Jungyeon Cho , Alex Lazarian , Ethan Vishniac

The molecular component of the Galaxy is comprised of turbulent, magnetized clouds, many of which are self-gravitating and form stars. To understand how these clouds' evolution may depend on their level of turbulence, mean magnetization,…

Astrophysics · Physics 2009-10-31 Eve C. Ostriker , Charles F. Gammie , James M. Stone

The mechanism of angular momentum transport in protoplanetary disks is fundamental to understand the distributions of gas and dust in the disks. The unprecedented, high spatial resolution ALMA observations taken toward HL Tau and subsequent…

Earth and Planetary Astrophysics · Physics 2017-08-23 Yasuhiro Hasegawa , Satoshi Okuzumi , Mario Flock , Neal J. Turner

We present a comprehensive study of MHD waves and instabilities in a weakly ionised system, e.g., an interstellar molecular cloud. We determine all the critical wavelengths of perturbations across which the sustainable wave modes can change…

Solar and Stellar Astrophysics · Physics 2011-04-01 Telemachos Ch. Mouschovias , Glenn E. Ciolek , S. A. Morton

Aims:We take advantage of the second data release of the Gaia space mission and the state-of-the-art astrometry delivered from very long baseline interferometry observations to revisit the structure and kinematics of the nearby Taurus…