On the Growth and Saturation of the Gyroresonant Streaming Instabilities
Journal Article
·
· The Astrophysical Journal (Online)
- Princeton Univ., NJ (United States); DOE/OSTI
- Princeton Univ., NJ (United States)
The self-regulation of cosmic-ray (CR) transport in the interstellar and intracluster media has long been viewed through the lenses of linear and quasi-linear kinetic plasma physics. Such theories are believed to capture the essence of CR behavior in the presence of self-generated turbulence but cannot describe potentially critical details arising from the nonlinearities of the problem. We utilize the particle-in-cell numerical method to study the time-dependent nonlinear behavior of the gyroresonant streaming instabilities, self-consistently following the combined evolution of particle distributions and self-generated wave spectra in one-dimensional periodic simulations. We demonstrate that the early growth of instability conforms to the predictions from linear physics, but that the late-time behavior can vary depending on the properties of the initial CR distribution. We emphasize that the nonlinear stages of instability depend strongly on the initial anisotropy of CRs—highly anisotropic CR distributions do not efficiently reduce to Alfvénic drift velocities, owing to reduced production of left-handed resonant modes. We derive estimates for the wave amplitudes at saturation and the timescales for nonlinear relaxation of the CR distribution and then demonstrate the applicability of these estimates to our simulations. Bulk flows of the background plasma due to the presence of resonant waves are observed in our simulations, confirming the microphysical basis of CR-driven winds.
- Research Organization:
- Krell Inst., Ames, IA (United States)
- Sponsoring Organization:
- National Science Foundation (NSF); Simons Foundation; USDOE National Nuclear Security Administration (NNSA)
- Grant/Contract Number:
- NA0002135
- OSTI ID:
- 1614477
- Journal Information:
- The Astrophysical Journal (Online), Journal Name: The Astrophysical Journal (Online) Journal Issue: 1 Vol. 882; ISSN 1538-4357
- Publisher:
- Institute of Physics (IOP)Copyright Statement
- Country of Publication:
- United States
- Language:
- English
Similar Records
COSMIC RAY TRANSPORT THROUGH GYRORESONANCE INSTABILITY IN COMPRESSIBLE TURBULENCE
THE NONLINEAR SATURATION OF THE NON-RESONANT KINETICALLY DRIVEN STREAMING INSTABILITY
Gyroresonant wave-particle interactions in a dynamic magnetosphere
Journal Article
·
Sun Apr 10 00:00:00 EDT 2011
· Astrophysical Journal
·
OSTI ID:21574772
THE NONLINEAR SATURATION OF THE NON-RESONANT KINETICALLY DRIVEN STREAMING INSTABILITY
Journal Article
·
Tue Mar 09 23:00:00 EST 2010
· Astrophysical Journal Letters
·
OSTI ID:21305101
Gyroresonant wave-particle interactions in a dynamic magnetosphere
Journal Article
·
Sat Sep 01 00:00:00 EDT 1990
· Journal of Geophysical Research; (United States)
·
OSTI ID:5452348