HR: 09:45h
AN: SH11A-08    [Abstracts]
TI: Voyager Observation of Galactic Cosmic Ray Elctrons in the Heliosheath
AU: * McDonald, F B
EM: fmcdonal@umd.edu
AF: Institute for Physical Science and Technology, Univeristy of Maryland, 4211 CSS Building, College Park, MD 20742, United States
AU: Webber, W R
EM: bwebber@nmsu.edu
AF: Department of Physics and Astronomy, New Mexico State University, P.O. Box 30001, Las Cruces, NM 88003, United States
AU: Stone, E C
EM: ecs@srl.caltech.edu
AF: California Institute of Technology, 1200 East California Blvd., Pasadena, CA 91109, United States
AU: Cummings, A C
EM: ace@citsrl.srl.caltech.edu
AF: California Institute of Technology, 1200 East California Blvd., Pasadena, CA 91109, 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@nasa.gov
AF: NASA/Goddard Space Flight Center, 8800 Greenbelt Road, Greenbelt, MD 20771, United States
AB: Voyager 1 observations of low-energy, (2.5-140 MeV), highly relativistic, galactic cosmic ray (GCR) electrons are important in studying the transport of energetic particles and the nature of transient disturbances in the heliosheath. These electrons originate as directly accelerated primaries, as interstellar secondaries from the decay of charged pions, or at low energies as knock-on electrons produced by the passage of higher energy cosmic rays through the interstellar medium. Inside 10 AU below some 60 MeV, Jovian electrons are the dominant electron component. Except for solar (out to 30 AU) and Jovian electrons there was no increase in the electron channels above the background level until V1 approached the termination shock in mid 2002. Since crossing the termination shock there has been a strong increase in the electron intensity with radial gradients of 6 – 75 MeV electrons that are inferred to be on the order of 18%/AU. The 10 MeV component appears to be especially sensitive to the passage of transient disturbances through the heliosheath. As V2 began observing an extended termination shock particle event in late 2004 there have been accompanying increases of 2.5 – 14 MeV electrons that are probably related to the interaction between interplanetary disturbances, the termination shock and the existing GCR electrons.
DE: 2104 Cosmic rays
DE: 2114 Energetic particles (7514)
DE: 2124 Heliopause and solar wind termination
SC: SPA-Solar and Heliospheric Physics [SH]
MN: 2007 Fall Meeting