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Title: Influence of the backreaction of streaming cosmic rays on magnetic field generation and thermal instability

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:
 [1] ;  [2]
  1. Institute of Physics of the Earth, Russian Academy of Sciences, 123995 Moscow (Russian Federation)
  2. Department of Physics, Golestan University, Basij Square, Gorgan (Iran, Islamic Republic of)
Publication Date:
OSTI Identifier:
22356689
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 788; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
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