Interplanetary scattering mean free path from 1 to 3 x 10/sup 3/ MV

Journal Article · Wed Mar 01 04:00:00 EST 1978 · J. Geophys. Res.; (United States)

DOI:https://doi.org/10.1029/JA083iA03p01157· OSTI ID:7276647

Zwickl, R D; Webber, W R

We have made a statistical study of published intensity-time profiles of proton and electron solar particle events from 1967 to 1974 in an attempt to examine systematically the temporal and rigidity dependence of the interplanetary scattering mean free path from approx.1 to 3 x 10/sup 3/ MV. The observed t/sub max/, the time from the release at the sun to the time of maximum flux at the spacecraft, from solar particle events that complied with a stringent selection criterion were interpreted in terms of a propagation model, with K/sub r/=K/sub 0/, to obtain the average radial scattering mean free path lambda/sub r/. We find that (1) lambda/sub r/ appears to be species indepentent when it is derived from proton and electron solar particle events, (2) lambda/sub r/ varies less than a factor of 2 from solar maximum to solar minimum, and (3) lambda/sub r/ is nearly rigidity independent below approx.500 MV. The values of lambda/sub r/ that we obtain at low rigidities are inconsistent with all current theoretical models that derive lambda/sub r/ from the interplanetary magnetic field fluctuations.

• Research Organization: Applied Physics Laboratory, Johns Hopkins University, Laurel, Maryland 20810
• OSTI ID: 7276647
• Journal Information: J. Geophys. Res.; (United States), Journal Name: J. Geophys. Res.; (United States) Vol. 83:A3; ISSN JGREA
• Country of Publication: United States
• Language: English

Related Subjects

640107* -- Astrophysics & Cosmology-- Planetary Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
BARYONS
ELECTRONS
ELEMENTARY PARTICLES
FERMIONS
HADRONS
INTERPLANETARY MAGNETIC FIELDS
INTERPLANETARY SPACE
LEPTONS
MAGNETIC FIELDS
MEAN FREE PATH
NUCLEONS
PROTONS
RADIATIONS
SCATTERING
SOLAR CYCLE
SOLAR ELECTRONS
SOLAR PARTICLES
SOLAR PROTONS
SOLAR RADIATION
SPACE
STELLAR RADIATION