HR: 0830h
AN: SH11D-1145    [PDF]
TI: Pickup ions generated near the sun during solar maximum
AU: * Allegrini, F
EM: fallegrini@swri.edu
AF: Southwest Research Institute, Space Science and Engineering Division 6220 Culebra Road, San Antonio, TX 78238-5166 United States
AU: Schwadron, N A
EM: nschwadron@swri.edu
AF: Southwest Research Institute, Space Science and Engineering Division 6220 Culebra Road, San Antonio, TX 78238-5166 United States
AU: Gloeckler, G
EM: gg10@umail.umd.edu
AF: University of Maryland, Department of Physics and Institute for Physical Science and Technology, College Park, MD 20742 United States
AU: Elliott, H A
EM: helliott@swri.edu
AF: Southwest Research Institute, Space Science and Engineering Division 6220 Culebra Road, San Antonio, TX 78238-5166 United States
AU: McComas, D J
EM: dmccomas@swri.edu
AF: Southwest Research Institute, Space Science and Engineering Division 6220 Culebra Road, San Antonio, TX 78238-5166 United States
AU: Posner, A
EM: aposner@swri.edu
AF: Southwest Research Institute, Space Science and Engineering Division 6220 Culebra Road, San Antonio, TX 78238-5166 United States
AB: In situ measurements have identified two main sources of pickup ions (PUIs): the interstellar source that dominates beyond $\sim$ 0.5 AU, and the inner source that dominates inside $\sim$ 0.5 AU. The inner-source PUIs are currently thought to be generated when solar wind passes through extremely small grains. The exiting solar wind particles, mainly neutrals at solar wind energies, are then ionized and picked up by the solar wind. The IDPs in this case must be small enough, a few tens of a nm at most, to act as thin foils by allowing the solar wind ions to pass through the grains without sputtering significant mass. The inner-source PUIs have been studied thus far at solar minimum. However, during solar maximum the solar wind pressure, the solar radiation pressure, and the number of coronal mass ejections increase. These effects may either push the minuscule inner source grains further out into the heliosphere or significantly deplete the grain population. As a consequence, we can use the differences in the inner-source PUI distribution functions observed during solar max and min to infer properties of the source population.
DE: 2129 Interplanetary dust
DE: 2152 Pickup ions
SC: SPA - Solar and Heliospheric Physics [SH]
MN: 2003 Fall Meeting