Evidence That Voyager 1 Exited the Solar Wind at ∼85 AU and Re-entered at ∼87 AU in August 2002 and February 2003.
Abstract
The LECP instrument on V1, V2 consists of a collection of solid-state detectors designed to perform measurements of ions ( ∼30keV to 10s of MeV) and electrons ( ∼28 keV to ∼10 MeV), including elemental composition over a range of energies (\>0.3 MeV/nuc) and species (H, He, C, N, O, Ne, etc). Salient features of the observations during 2002-2003 are as follows: (a) A gradual increase in ∼1 MeV proton intensity in late 2000 culminated in an 100-fold step increase in mid-2002 lasting for >6 months and ending within a few hours in early 2003. (b) The step increase was seen in energies ranging from ∼40 keV to >70 MeV for protons and >0.35 MeV for electrons. (c) Large intensity fluctuations lasting from <1 to several days were present coherently in all energies and species throughout the period. (d) The composition of H, He, O and C are consistent with an ACR or PUI source. (e) Outward streaming anisotropies show that the particle source lies inside the V1 location. (f) Generalized (non-linear) Compton-Getting fits to the angular distributions show the convection velocity changed from 300 km/s to <50km/s and back to ∼230km/s before, during, and after the increase, respectively. Post-re-entry observations show frequent inward and some outward proton flows, suggesting a significant radial component of the IMF. The observations will be discussed in the context of current theoretical models of the interaction between the heliosphere and the local interstellar medium.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2003
- Bibcode:
- 2003AGUFMSH12B..03K
- Keywords:
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- 2124 Heliopause and solar wind termination