HR: 15:05h
AN: SH43B-06    [Abstracts]
TI: Effects of Multiple Intersection between Field Lines and the Termination Shock on Particle Anisotropies and Energy Spectra Observed by Voyager-1
AU: * Kota, J
EM: kota@lpl.arizona.edu
AF: The University of Arizona, University of Arizona Lunr and Planetary Laboratory, Tucson, AZ 85721-0092 United States
AU: Jokipii, J R
EM: jokipii@lpl.arizona.edu
AF: The University of Arizona, University of Arizona Lunr and Planetary Laboratory, Tucson, AZ 85721-0092 United States
AB: It is likely that, in 2002-2004, Voyager-1 was still inside the termination shock, but its magnetic field line had intersected the shock between V-1 and the Sun. This may well occur if the field line intersects the shock multiple times, which can happen for a number of plausible reasons. We discuss the effects of multiple intersection in the light of new findings of V-1 since crossing the shock in December 2004. We consider the effects of such multiple intersection on the pitch-angle anisotropies and energy spectra of energetic particles near the shock. The most spectacular particle signatures of the shock-crossing of V-1 were the increase of low-energy particle fluxes, the disapperance of high beaming anisotropies, and the small variability prevailing since the crossing. On the other hand, the spectrum still has not unfolded into a smooth power-law spectrum anticipated at the shock. We stress that the shock with multiple intersection need not produce a uniform power-law everywhere along the shock. Instead, a two-population spectrum, similar to that observed by Voyager-1, may be expected when flirting field lines cross and recross the shock. We interpret the two-population spectra observed by V-1 as a signature of acceleration at different sites. The implication of the apparent double power-law spectra of the termination shock particle population will be addressed.
DE: 2114 Energetic particles (7514)
DE: 2124 Heliopause and solar wind termination
DE: 2134 Interplanetary magnetic fields
SC: SPA-Solar and Heliospheric Physics [SH]
MN: Fall Meeting 2005