HR: 08:15h
AN: SH41B-02 [Abstracts]
TI: Continuing the Search for the Heliosheath by Voyager 1
AU: * Ness, N F
EM: nfness@udel.edu
AF: University of Delaware, Bartol Research Institute
217 Sharp Laboratory, Newark, DE 19716
United States
AU: Burlaga, L F
EM: leonard.f.burlaga@nasa.gov
AF: NASA-Goddard Space Flight Center, Code 695, Building 21
Planetary Magnetospheres Branch, Greenbelt, MD 20771
United States
AU: Acuna, M H
EM: mario.acuna@gsfc.nasa.gov
AF: NASA-Goddard Space Flight Center, Code 695, Building 21
Planetary Magnetospheres Branch, Greenbelt, MD 20771
United States
AU: McDonald, F B
EM: fm27@umail.umd.edu
AF: University of Maryland, Institute for Physical Science & Technology, College Park, MD 20742
United States
AU: Stone, E C
EM: ecs@srl.caltech.edu
AF: California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109-8099
United States
AB:
The Voyager 1 spacecraft, V1, has measured the Heliospheric Magnetic Field (HMF) since launch in 1977. This covers more than
a full 22 years solar magnetic cycle. V1 data shows that the HMF, on average, is well described by Parker's archimedean
spiral structure out to 95 AU and 35 degrees north heliographic latitude if due account is made for time variations of the
source HMF field strength and solar wind velocity. The V1 magnetic field observations do not provide any evidence for entry
into or exit from a subsonic SW region such as the heliosheath is expected to be nor any crossings of the
heliosphere-heliosheath interface, the Termination Shock (TS), as has been reported at 85 AU by Krimigis et al [2003]. Merged
Interaction Regions or transient flows are identified by increased fields and associated decreases in the flux of >70
MeV/nuc cosmic rays which are then followed by a recovery of the CR flux. This CR-B relationship has been identified and
studied since 1982 when V1 was at 11 AU. A study of magnetic field fluctuations, up to 0.26 Hz, in 2001-2004, shows periods
of increases of the daily mean standard deviation, which is a direct measure of the energy in the magnetic field variations.
We are unable to identify any coherent correlation of these periods with the reported TS and heliosheath crossings.
DE: 2104 Cosmic rays
DE: 2124 Heliopause and solar wind termination
DE: 2134 Interplanetary magnetic fields
DE: 2139 Interplanetary shocks
DE: 2159 Plasma waves and turbulence
SC: SPA-Solar and Heliospheric Physics [SH]
MN: 2004 AGU Fall Meeting