Cosmic-ray scattering in simulated interplanetary magnetic field fluctuations

Journal Article · Fri Feb 01 04:00:00 EST 1980 · Astrophys. J.; (United States)

DOI:https://doi.org/10.1086/157711· OSTI ID:5364561

Owens, A J; Gombosi, T

We study the diffusion of cosmic rays in simulated interplanetary magnetic-field fluctuations using the Monte Carlo pitch-angle scattering technique of Jones, Kaiser, and Birmingham. Our calculations are based on the ''slab'' model, with transverse (x, y) field fluctuations (B') varying only along the average magnetic field direction (z). The rms variation of B' is one-half the average field for each of the independent transverse field components, and each fluctuating field component has a power spectrum p(k)=A/(1+(kL)/sup 1.5/), as observed in interplanetary space. The derived pitch-angle scattering coefficient is used to calculate the spatial diffusion coefficient applicable near Earth. There is significant scattering near the pitch-angle cosine ..mu..=0. Our calculated parallel diffusion coefficient is within about 20)% of that predicted by quasi-linear theory, for particles with cyclotron radii r0.03=(en-dash1) times the field correlation length (rigidities 0.4--15 GV).

• Research Organization: Barton Reseach Foundation of the Franklin Institute, University of Delaware, Newark
• OSTI ID: 5364561
• Journal Information: Astrophys. J.; (United States), Journal Name: Astrophys. J.; (United States) Vol. 235:3; ISSN ASJOA
• Country of Publication: United States
• Language: English

Related Subjects

640101* -- Astrophysics & Cosmology-- Cosmic Radiation
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
COSMIC RADIATION
ENERGY SPECTRA
FLUCTUATIONS
HYDROMAGNETIC WAVES
INCLINATION
INTERPLANETARY MAGNETIC FIELDS
INTERPLANETARY SPACE
IONIZING RADIATIONS
MAGNETIC FIELDS
RADIATIONS
SCATTERING
SPACE
SPECTRA
VARIATIONS