Influence of the backreaction of streaming cosmic rays on magnetic field generation and thermal instability
Abstract
Using a multifluid approach, we investigate streaming and thermal instabilities of the electron-ion plasma with homogeneous cold cosmic rays propagating perpendicular to the background magnetic field. Perturbations are also considered to be across the magnetic field. The backreaction of cosmic rays resulting in strong streaming instabilities is taken into account. It is shown that, for sufficiently short wavelength perturbations, the growth rates can exceed the growth rate of cosmic-ray streaming instability along the magnetic field, found by Nekrasov and Shadmehri, which is in turn considerably larger than the growth rate of the Bell instability. The thermal instability is shown not to be subject to the action of cosmic rays in the model under consideration. The dispersion relation for the thermal instability has been derived, which includes sound velocities of plasma and cosmic rays and Alfvén and cosmic-ray streaming velocities. The relation between these parameters determines the kind of thermal instability ranging from the Parker to the Field instabilities. The results obtained can be useful for a more detailed investigation of electron-ion astrophysical objects, such as supernova remnant shocks, galaxy clusters, and others, including the dynamics of streaming cosmic rays.
- Authors:
-
- Institute of Physics of the Earth, Russian Academy of Sciences, 123995 Moscow (Russian Federation)
- Department of Physics, Golestan University, Basij Square, Gorgan (Iran, Islamic Republic of)
- Publication Date:
- OSTI Identifier:
- 22356689
- Resource Type:
- Journal Article
- Journal Name:
- Astrophysical Journal
- Additional Journal Information:
- Journal Volume: 788; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0004-637X
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ALFVEN WAVES; ASTROPHYSICS; COSMIC RADIATION; DISPERSION RELATIONS; DISTURBANCES; GALAXY CLUSTERS; INSTABILITY; IONS; MAGNETIC FIELDS; PERTURBATION THEORY; PLASMA; SOUND WAVES; VELOCITY; WAVELENGTHS
Citation Formats
Nekrasov, Anatoly K., and Shadmehri, Mohsen. Influence of the backreaction of streaming cosmic rays on magnetic field generation and thermal instability. United States: N. p., 2014.
Web. doi:10.1088/0004-637X/788/1/47.
Nekrasov, Anatoly K., & Shadmehri, Mohsen. Influence of the backreaction of streaming cosmic rays on magnetic field generation and thermal instability. United States. https://doi.org/10.1088/0004-637X/788/1/47
Nekrasov, Anatoly K., and Shadmehri, Mohsen. 2014.
"Influence of the backreaction of streaming cosmic rays on magnetic field generation and thermal instability". United States. https://doi.org/10.1088/0004-637X/788/1/47.
@article{osti_22356689,
title = {Influence of the backreaction of streaming cosmic rays on magnetic field generation and thermal instability},
author = {Nekrasov, Anatoly K. and Shadmehri, Mohsen},
abstractNote = {Using a multifluid approach, we investigate streaming and thermal instabilities of the electron-ion plasma with homogeneous cold cosmic rays propagating perpendicular to the background magnetic field. Perturbations are also considered to be across the magnetic field. The backreaction of cosmic rays resulting in strong streaming instabilities is taken into account. It is shown that, for sufficiently short wavelength perturbations, the growth rates can exceed the growth rate of cosmic-ray streaming instability along the magnetic field, found by Nekrasov and Shadmehri, which is in turn considerably larger than the growth rate of the Bell instability. The thermal instability is shown not to be subject to the action of cosmic rays in the model under consideration. The dispersion relation for the thermal instability has been derived, which includes sound velocities of plasma and cosmic rays and Alfvén and cosmic-ray streaming velocities. The relation between these parameters determines the kind of thermal instability ranging from the Parker to the Field instabilities. The results obtained can be useful for a more detailed investigation of electron-ion astrophysical objects, such as supernova remnant shocks, galaxy clusters, and others, including the dynamics of streaming cosmic rays.},
doi = {10.1088/0004-637X/788/1/47},
url = {https://www.osti.gov/biblio/22356689},
journal = {Astrophysical Journal},
issn = {0004-637X},
number = 1,
volume = 788,
place = {United States},
year = {Tue Jun 10 00:00:00 EDT 2014},
month = {Tue Jun 10 00:00:00 EDT 2014}
}