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Title: A Kinetic Study of the Saturation of the Bell Instability
The nonresonant cosmic ray instability, predicted by Bell (2004), is thought to play an important role in the acceleration and confinement of cosmic rays (CR) close to supernova remnants. Despite its importance, the exact mechanism responsible for the saturation of the instability has not been determined, and there is no first-principle prediction for the amplitude of the saturated magnetic field. Using a survey of self-consistent hybrid simulations (with kinetic ions and fluid electrons), we study the non-linear evolution of the Bell instability as a function of the parameters of the CR population. We find that saturation is achieved when the magnetic pressure in the amplified field is comparable to the initial CR momentum flux.
Authors:
; ; ;
Award ID(s):
1936393
Publication Date:
NSF-PAR ID:
10293949
Journal Name:
37th International Cosmic Ray Conference (ICRC2021)
Volume:
395
Page Range or eLocation-ID:
483
Sponsoring Org:
National Science Foundation
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