HR: 09:45h
AN: SA31A-05    [Abstracts]
TI: Photoelectron transport at Titan, Saturn, and Earth: comparative approach
AU: * Galand, M
EM: mgaland@bu.edu
AF: Center for Space Physics / Boston University, 725 Commonwealth Avenue, Boston, MA 02215 United States
AU: Yelle, R V
EM: yelle@lpl.arizona.edu
AF: Lunar & Planetary Laboratory / University of Arizona, 1629 E. University Blvd, Tucson, AZ 85721-0092 United States
AB: Solar irradiance in the extreme ultra-violet and X-ray spectral range is a major source of variability in planetary upper atmospheres through photoionization and heating processes. The induced photoelectrons have enough energy to also interact with the atmospheric population. Their transport is important for ionospheric densities and temperatures. As support of the on-going Cassini mission we recently upgraded the version of Titan's multistream electron transport model and adopted it to the atmosphere of Saturn. The goals of such calculations, unprecedented for Saturn, are to compute the electron/ion production rates induced by energetic electrons and the heating rate associated with the energy transfer between suprathermal electrons and ionospheric electrons. We will discuss how sensitive these quantities are with solar activity and compare solar-induced to photoelectron-induced electron productions. Saturn and its largest moon, Titan, do not share the same atmospheric neutral species, whereas Earth and Titan have similar atmospheric constituents at different distances from the Sun. Therefore comparing the transport of photoelectrons between these three bodies, primary goal of this study, is of particular interest.
UR: http://www.bu.edu/csp/uv/cp-aeronomy/aeronomy-sol-sys.html
DE: 2423 Ionization mechanisms
DE: 2479 Solar radiation and cosmic ray effects
DE: 5729 Ionospheres (2459)
DE: 6207 Comparative planetology
DE: 6275 Saturn
SC: SPA-Aeronomy [SA]
MN: 2005 Joint Assembly