HR: 0800h
AN: SH31A-1149    [Abstracts]
TI: Enhancements of He$^+$ at Interplanetary Disturbances: A Survey
AU: * Kucharek, H
EM: Harald.Kucharek@unh.edu
AF: University of New Hampshire, Space Science Center Morse Hall, 39 College Road, Durham, NH 03824 United States
AU: Moebius, E
EM: Eberhard.Moebius@unh.edu
AF: University of New Hampshire, Space Science Center Morse Hall, 39 College Road, Durham, NH 03824 United States
AU: Lu, Y
EM: yipinl@cisunix.unh.edu
AF: University of New Hampshire, Space Science Center Morse Hall, 39 College Road, Durham, NH 03824 United States
AU: Smith, C
AF: University of New Hampshire, Space Science Center Morse Hall, 39 College Road, Durham, NH 03824 United States
AU: Klecker, B
EM: Berndt.Klecker@mpe.mpg.de
AF: Max-Planck-Institut fuer extraterrestrische Physik, Postfach 1603, Garching, 85740 Germany
AU: Farrugia, C
EM: charlie.farrugia@unh.edu
AF: University of New Hampshire, Space Science Center Morse Hall, 39 College Road, Durham, NH 03824 United States
AU: Popecki, M
EM: mark.popecki@unh.edu
AF: University of New Hampshire, Space Science Center Morse Hall, 39 College Road, Durham, NH 03824 United States
AU: Galvin, A
EM: toni.galvin@unh.edu
AF: University of New Hampshire, Space Science Center Morse Hall, 39 College Road, Durham, NH 03824 United States
AU: Hilchenbach, M
EM: martin@linmpe.mpg.de
AF: Max-Planck-Institut fuer Sonnensystemforschung, Max-Planck-Str, Katlenburg-Lindau, 37819 Germany
AU: Bochsler, P
EM: peter.bochsler@soho.unibe.ch
AF: University of Bern, Sidlerstrasse 5, Bern, 3012 Switzerland
AB: Recent observations with ACE/SEPICA and SOHO CELIAS STOF have shown that energetic He$^+$ is after H$^+$ and He$^{2+}$ the third most abundant energetic particle population in the heliosphere. The He$^+$/He$^{2+}$ ratio in the energetic particle population can reach unusually high values; in the energy range of 250keV/n -800keV/n ratios close to unity. The major source of the energetic He+ has been identified to be interplanetary pickup ions that are preferentially accelerated at CIR's, TIR's, and interplanetary traveling shocks. Since, compared to solar wind ions pickup ions are already suprathermal, any accelerator can create an enhancement in the energetic He$^+$/He$^{2+}$ ratio. In our survey of energetic helium over three years (1998-2000) from STOF and SEPICA we have identified additional discontinuities and magnetic field signatures, such as current sheet crossings, flows, and enhanced magnetic turbulence, which are associated with an enhancement in He$^+$/He$^{2+}$ ratio.
DE: 2102 Corotating streams
DE: 2109 Discontinuities
DE: 2139 Interplanetary shocks
DE: 2152 Pickup ions
SC: SPA-Solar and Heliospheric Physics [SH]
MN: 2004 AGU Fall Meeting