HR: 09:00h
AN: SH41B-05    [Abstracts]
TI: Voyager-1 Observations of MeV Ions and Electrons in the Vicinity of the Heliospheric Termination Shock
AU: * McDonald, F B
EM: fm27@umail.umd.edu
AF: Institute for Physical Science and Technology, University of Maryland, CSS Bldg 224, Rm 3245, College Park, MD 20742 United States
AU: Stone, E C
EM: ecs@srl.caltech.edu
AF: California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125 United States
AU: Cummings, A C
EM: ace@srl.caltech.edu
AF: California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125 United States
AU: Heikkila, B C
EM: bryant@mail630.gsfc.nasa.gov
AF: NASA/Goddard Space Flight Center, 8800 Greenbelt Road, Greenbelt, MD 20771 United States
AU: Lal, N
EM: Nand.Lal.1@gsfc.nasa.gov
AF: NASA/Goddard Space Flight Center, 8800 Greenbelt Road, Greenbelt, MD 20771 United States
AU: Webber, W R
EM: bwebber@nmsu.edu
AF: Department of Physics and Astronomy, New Mexico State University PO Box 30001, Las Cruces, NM 88003 United States
AB: Beginning in 2002.5 at a heliospheric distance of some 85AU, the CRS (Cosmic Ray Subsystem) experiment on Voyager-1 observed two large increases in MeV ions and electrons accompanied by more modest increases in Galactic and Anomaloous cosmic rays (GCR and ACRs). The first event persisted for some 6.5 months and was terminated by the passage of a large outward moving interplanetary disturbance. The second event, which began in 2003.62, is still in progress more than a year later. We have interpreted these events as the expected energetic particle precursors as Voyager-1 approaches the heliospheric termination shock and we have termed them TSP (Termination Shock Particle) increases. There are small, but significant, differences between TSP 1 and 2 both in the time history of the ions and electrons and in the short term (13 - 52 day) variations. In addition the GCR and ACR flux levels are somewhat smaller for the 2nd event. These TSP events have not yet been observed at Voyager-2, which is at a heliocentric distance some 18AU less than Voyager-1. However, at Voyager-2 there is a remarkable series of solar/interplanetary energetic particle events associated with specific episodes of solar activity. The effects of these interplanetary transients is clearly evident in the time history of the Voyager-1 TSPs, thus providing another means of probing this new region of space.
DE: 7500 SOLAR PHYSICS, ASTROPHYSICS, AND ASTRONOMY
SC: SPA-Solar and Heliospheric Physics [SH]
MN: 2004 AGU Fall Meeting