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Related papers: Hydrodynamical instability of extragalactic strati…

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Transverse stratification is a common intrinsic feature of astrophysical jets. There is growing evidence that jets in radio galaxies consist of a fast low density outflow at the jet axis, surrounded by a slower, denser, extended jet. The…

High Energy Astrophysical Phenomena · Physics 2014-11-20 Z. Meliani , R. Keppens

Herbig-Haro (HH) jets are commonly thought of as homogeneous beams of plasma traveling at hypersonic velocities. Structure within jet beams is often attributed to periodic or ``pulsed'' variations of conditions at the jet source.…

Astrophysics · Physics 2011-02-11 Kristopher Yirak , Adam Frank , Andrew J. Cunningham , Sorin Mitran

The stability of thin homogeneous gaseous disk with step discontinuity of velocity and density profile has been investigated analytically in the limitary case of large compressibility and numerically at spatially separated velocity and…

Astrophysics · Physics 2007-05-23 C. M. Bezborodov , J. V. Mustsevaya , V. V. Mustsevoy

Electron-scale Kelvin-Helmholtz instabilities (ESKHI) are found in several astrophysical scenarios. Naturally ESKHI is subject to a background magnetic field, but an analytical dispersion relation and an accurate growth rate of ESKHI under…

Plasma Physics · Physics 2025-02-25 Yao Guo , Dong Wu , Jie Zhang

We present full-track high-resolution radio observations of the jet of the galaxy M87 at 8 and 15 GHz. These observations were taken over three consecutive days in May 2009 using the Very Long Baseline Array (VLBA), one antenna of the Very…

Astrophysics of Galaxies · Physics 2023-10-31 A. S. Nikonov , Y. Y. Kovalev , E. V. Kravchenko , I. N. Pashchenko , A. P. Lobanov

The interaction between various wavelike structures in screeching jets is considered via both experimental measurements and linear stability theory. Velocity snapshots of screeching jets are used to produce a reduced order model of the…

We study the linear theory of Kelvin-Helmholtz instability in a layer of ions and neutrals with finite thickness. In the short wavelength limit the thickness of the layer has a negligible effect on the growing modes. However, perturbations…

Astrophysics · Physics 2008-11-26 Mohsen Shadmehri , Turlough P. Downes

We report the discovery of an extremely curved jet in the radio-loud quasar PKS2136+141. Multi-frequency Very Long Baseline Array (VLBA) images show a bending jet making a turn-around of 210 degrees in the plane of the sky, which is, to our…

Studies have shown that in sheared $\mathbf{E}\times\mathbf{B}$ flows in an inhomogeneous ionospheric plasma, the gradient drift (GDI) or the Kelvin-Helmholtz (KHI) instability may grow. This work examines the conditions that cause one of…

Plasma Physics · Physics 2021-06-02 C. Rathod , B. Srinivasan , W. Scales

We investigate the launching and stability of extragalactic jets through nonlinear magnetohydrodynamic (MHD) simulation and linear eigenmode analysis. In the simulations of jet evolution, a small-scale equilibrium magnetic arcade is twisted…

High Energy Astrophysical Phenomena · Physics 2011-02-11 C. S. Carey , C. R. Sovinec

Flow-induced instabilities are relevant for the storage and dynamics of magnetic fields in stellar convection zones and possibly also in other astrophysical contexts. We continue the study started in the first paper of this series by…

Astrophysics · Physics 2009-11-13 V. Holzwarth , D. Schmitt , M. Schuessler

We study the effect of plasma composition on the dynamics and morphology of the relativistic astrophysical jets. Our work is based on a relativistic total variation diminishing (TVD) simulation code. We use a relativistic equation of state…

High Energy Astrophysical Phenomena · Physics 2023-08-08 Raj Kishor Joshi , Indranil Chattopadhyay

We study the efficiency of radiation in driving jets around black holes. Including general relativity for the radiation driving, we also show that the radiation field is affected by strong gravitational field in non linear manner, making…

Space Physics · Physics 2021-11-10 Mukesh Kumar Vyas

MHD jet equilibria that depend on source properties are obtained using a simplified model for stationary, axisymmetric and rotating magnetized outflows. The present rotation laws are more complex than previously considered and include a…

Astrophysics · Physics 2009-10-31 Thibaut Lery , Adam Frank

In the present paper, we study the evolutionary conditions for Kelvin--Helmholtz (KH) instability in a high-temperature solar surge observed in NOAA AR11271 using the Solar Dynamics Observatory data on 2011 August 25. We study the…

Solar and Stellar Astrophysics · Physics 2015-06-23 I. Zhelyazkov , R. Chandra , A. K. Srivastava , T. Mishonov

We propose a different type of Landau instability in trapped Bose-Einstein condensates by a helically moving environment. In the presence of quantized vortices, the instability can cause spontaneous radiation and amplification of Kelvin…

Other Condensed Matter · Physics 2010-11-29 Hiromitsu Takeuchi , Kenichi Kasamatsu , Makoto Tsubota

The Kelvin-Helmholtz instability is well known to be capable of converting well-ordered flows into more disordered, even turbulent, flows. As such it could represent a path by which the energy in, for example, bowshocks from stellar jets…

Astrophysics of Galaxies · Physics 2011-11-03 Aoife C. Jones , Turlough P. Downes

Electron-scale surface waves are shown to be unstable in the transverse plane of a shear flow in an initially unmagnetized plasma, unlike in the (magneto)hydrodynamics case. It is found that these unstable modes have a higher growth rate…

Plasma Physics · Physics 2015-08-26 E. P. Alves , T. Grismayer , R. A. Fonseca , L. O. Silva

We present the results of a three-dimensional, relativistic, hydrodynamic simulation of a precessing jet into which a compact blob of matter is injected. A comparison of synthetic radio maps computed from the hydrodynamic model, taking into…

Relations between the observed quantities for a beamed radio jet, apparent transverse speed and apparent luminosity (beta_app,L), and the intrinsic quantities, Lorentz factor and intrinsic luminosity (gamma,L_o), are investigated. The…