Wave-Particle Interactions for 3He-Rich Events and Large Solar Particle Events: ISEE-3
B.T. Tsurutani1,3, L.D. Zhang1, Glenn M. Mason2,4,
Gurbax Lakhina1, Tohru Hada5, John K. Arballo1,
Ronald D. Zwickl3
1 Jet Propulsion Laboratory, 4800 Oak Grove Drive, Pasadena,
California 91109
2 Department of Physics, University of Maryland, College
Park, Maryland 20742
3 National Oceanic and Atmospheric Administration, Space
Environment Laboratory, Code R/E/SE, Boulder, Colorado 80303
4 Institute for Physical Science and Technology, University
of Maryland, College Park, Maryland 25742
5 ESST Kyushu University, Kasuga 816-8580, Japan
ISEE-3 energetic particles and MHD waves are studied to investigate
particle propagation and scattering between the source near the Sun and
the Earth (1 AU). For 3He rich events, simultaneous interplanetary
magnetic spectra are measured. The interplanetary turbulence through which
the particles have traversed is found to be fairly low. This can be interpreted
as indicating that either low turbulence fields are necessary for the particles
to propagate long (~1.3 AU) distances, or that the fields above active
regions producing 3He events have a lack of waves/turbulence.
If the former is the case, there may be many 3He events at the
sun that are not detected at 1 AU. The largest solar particle events are
analyzed to investigate the possibilities of local wave generation at 1
AU. No evidence for wave instability is found at either the leading edge
or at the point of peak flux. Our results indicate that interplanetary
solar wind "fossil" waves are the important scatterers for particles coming
from the Sun to 1 AU, and it is the quiet to intermediate level of IMF
activity that are associated with the 3He scatter-free events.
Lastly we intercompare the particle mean free paths calculated from resonant
wave-particle interactions
and from those derived from 3He++ intensity and anisotropy
time profiles . By including
measured wave polarization and wave k directions, we decrease the
previously noted discrepancy between
and by a factor of ~ 2.
We note that is determined
by the process of pitch angle scattering from ~ 00 to ~ 1800,
while by that from ~ 00
to ~ < 900. But the scattering across 900 pitch
angle is a different process. Therefore the remaining discrepancy between
and may lie in the fact
that diffusion across 900 pitch angle is much slower than resonant
scattering near 00 and 1800pitch angle.