English
Related papers

Related papers: The Parker Instability in Disk Galaxies

200 papers

We present the results of linear analysis and two-dimensional local magnetohydrodynamic (MHD) simulations of the Parker instability, including the effects of cosmic rays (CRs), in magnetized gas disks (galactic disks). As an unperturbed…

Astrophysics · Physics 2009-11-10 Takuhito Kuwabara , Kenji Nakamura , C. M. Ko

Parker instability arises from the presence of magnetic fields in a plasma in a gravitational field such as the interstellar medium (ISM), wherein the magnetic buoyant pressure expels the gas and causes the gas to move along the field…

High Energy Astrophysical Phenomena · Physics 2011-09-07 Chih-Yueh Wang , Ying-Yi Lo , Chung-Ming Ko

This study investigates Parker instability in an interstellar medium (ISM) near the Galactic plane using three-dimensional magneto-hydrodynamic simulations. Parker instability arises from the presence of a magnetic field in a plasma,…

High Energy Astrophysical Phenomena · Physics 2011-01-06 Ying-Yi Lo , Chung-Ming Ko , Chih-Yueh Wang

We study the linear properties, nonlinear saturation and a steady, strongly nonlinear state of the Parker instability in galaxies. We consider magnetic buoyancy and its consequences with and without cosmic rays. Cosmic rays are described…

The effect of cosmic rays on the Parker-Jeans instability in magnetized self-gravitating gaseous disks is studied by three-dimensional magnetohydrodynamic (MHD) simulations with cosmic rays taken as a massless fluid with notable pressure.…

High Energy Astrophysical Phenomena · Physics 2020-08-26 Takuhito Kuwabara , Chung Ming Ko

A linear stability analysis of a multi-component and magnetized Galactic disk model is presented. The disk model uses the observed stratifications for the gas density and gravitational acceleration at the solar neighborhood and, in this…

Astrophysics · Physics 2009-10-31 Jongsoo Kim , Jose Franco , S. S. Hong , Alfredo Santillan , Marco A. Martos

The Parker instability, which has been considered as a process governing the structure of the interstellar medium, is induced by the buoyancy of magnetic field and cosmic rays. In previous studies, while the magnetic field has been fully…

Astrophysics · Physics 2009-11-07 Dongsu Ryu , Jongsoo Kim , Seung Soo Hong , T. W. Jones

We investigate the effects of rotation on the evolution of the Parker instability in an exponentially-stratified and uniformly-rotating magnetized gas disk by carrying out three-dimensional numerical simulations with an isothermal…

Astrophysics · Physics 2009-11-06 Jongsoo Kim , Dongsu Ryu , T. W. Jones

Using an isothermal MHD code, we have performed three-dimensional, high-resolution simulations of the Parker instability. The initial equilibrium system is composed of exponentially-decreasing isothermal gas and magnetic field (along the…

Astrophysics · Physics 2009-10-30 Jongsoo Kim , S. S. Hong , Dongsu Ryu , T. W. Jones

We present a detailed study of the growth of the Parker instability in a differentially rotating disk embedded in an azimuthal equilibrium magnetic field, such as the interstellar gas or an accretion disk. Basic properties of the…

Astrophysics · Physics 2007-05-23 T. Foglizzo , M. Tagger

The Parker instability, a Rayleigh-Taylor like instability of thermal gas supported against gravity by magnetic fields and cosmic rays, is thought to be dynamically important for galaxy evolution, possibly promoting molecular cloud…

Astrophysics of Galaxies · Physics 2020-03-25 Evan Heintz , Chad Bustard , Ellen Zweibel

We present 2D, ideal-MHD numerical simulations of the Parker instability in a multi-component warm disk model. The calculations were done using two numerical codes with different algorithms, TVD and ZEUS-3D. The outcome of the numerical…

Astrophysics · Physics 2009-10-31 Alfredo Santillan , Jongsoo Kim , Jose Franco , Marco Martos , S. S. Hong , Dongsu Ryu

We model the Parker instability in vertically stratified isothermal gas using non-ideal MHD three-dimensional simulations. Rotation, especially differential, more strongly and diversely affects the nonlinear state than the linear stage…

Astrophysics of Galaxies · Physics 2023-05-08 Devika Tharakkal , Anvar Shukurov , Frederick A. Gent , Graeme R. Sarson , Andrew Snodin

We investigate the nonlinear effects of uniform rotation on the Parker instability in an exponentially-stratified disk through high-resolution simulations. During the linear stage, the speed of gas motion is subsonic and the evolution with…

Astrophysics · Physics 2007-05-23 Jongsoo Kim , Dongsu Ryu , T. W. Jones

In galactic disks, the Parker instability results when non-thermal pressure support exceeds a certain threshold. The non-thermal pressures considered in the Parker instability are cosmic ray pressure and magnetic pressure. This instability…

High Energy Astrophysical Phenomena · Physics 2023-08-02 Roark Habegger , Ellen G. Zweibel , Sherry Wong

We present a new systematic way of setting up galactic gas disks based on the assumption of detailed hydrodynamic equilibrium. To do this, we need to specify the density distribution and the velocity field which supports the disk. We first…

Astrophysics of Galaxies · Physics 2015-05-18 Hsiang-Hsu Wang , Ralf S. Klessen , Cornelis P. Dullemond , Frank C. van den Bosch , Burkhard Fuchs

Parker instability leads to the formation of tangential discontinuities in a magnetic field and subsequent magnetic reconnection due to a numerical and/or an explicit resistivity. In this paper we investigate the role of the uniform,…

Astrophysics · Physics 2009-11-07 Grzegorz Kowal , Michal Hanasz , Katarzyna Otmianowska-Mazur

Magnetic buoyancy (MBI) and Parker instabilities are strong, generic instabilities expected to occur in most astrophysical systems with sufficiently strong magnetic fields. In galactic and accretion discs, large-scale magnetic fields are…

Astrophysics of Galaxies · Physics 2025-04-11 Yasin Qazi , Anvar. Shukurov , Frederick. A. Gent , Devika. Tharakkal , Abhijit. B. Bendre

We study the final equilibrium states of the Parker instability arising from an initially unstable cylindrical equilibrium configuration of gas in the presence of a radial gravitational field and a longitudinal magnetic field. The aim of…

Astrophysics of Galaxies · Physics 2010-11-30 F. J. Sanchez-Salcedo , A. Santillan

We study the nonlinear evolution of the magnetic buoyancy instability in rotating and non-rotating gas layers using numerical solutions of non-ideal, isothermal MHD equations. The unstable magnetic field is either imposed through the…

Astrophysics of Galaxies · Physics 2025-09-09 Yasin Qazi , Anvar Shukurov , Devika Tharakkal , Frederick A. Gent
‹ Prev 1 2 3 10 Next ›