HR: 0800h
AN: SH52A-0906    [Abstracts]
TI: An Overview of SAMPEX/MAST Measurements of High Energy Ionic Charge States in Gradual Solar Energetic Particle Events
AU: * Labrador, A W
EM: labrador@srl.caltech.edu
AF: California Institute of Technology, Mail Code 220-47, Pasadena, CA 91125, United States
AU: Leske, R A
EM: ral@srl.caltech.edu
AF: California Institute of Technology, Mail Code 220-47, Pasadena, CA 91125, United States
AU: Cohen, C M
EM: cohen@srl.caltech.edu
AF: California Institute of Technology, Mail Code 220-47, Pasadena, CA 91125, United States
AU: Mewaldt, R A
EM: rmewaldt@srl.caltech.edu
AF: California Institute of Technology, Mail Code 220-47, Pasadena, CA 91125, United States
AU: Stone, E C
EM: ecs@srl.caltech.edu
AF: California Institute of Technology, Mail Code 220-47, Pasadena, CA 91125, United States
AU: von Rosenvinge, T T
EM: tycho@milkyway.gsfc.nasa.gov
AF: NASA/Goddard Space Flight Center, Code 661, Greenbelt, MD 20771, United States
AB: The MAST experiment aboard SAMPEX employs a geomagnetic rigidity filter technique to yield measurements of mean ionic charge states in large solar energetic particle events. Elements measured include N, O, Ne, Mg, Si, and Fe, with energies of 15-60 MeV/nuc (N, O, Ne), 20-60 MeV/nuc (Mg, Si), and 25-90 MeV/nuc (Fe). These measurements, extending from 1992 to 2006, remain the highest energy direct measurements of mean ionic charge states in SEP events, overlapping ACE and STEREO measurements in energy. The measured charge states are probes of source materials and conditions of particle transport and are useful in multi-spacecraft studies of large SEP events. Iron charge states measured by MAST range from ~+10 to ~+22 in various SEP events, corresponding to plasma temperatures from ~1.5 MK to ~16 MK and indicating the possible presence of flare material in some of these events. In this poster, we will review the current state of the charge states analysis, including development of the analysis technique and extension of the analysis to new events, such as the December 2006 large SEP events and other previously unanalyzed SEP events selected with the help of ACE/SIS fluence data. We will also show Q(Fe) correlation with ACE/SIS Fe/O ratios in the same energy ranges.
DE: 7513 Coronal mass ejections (2101)
DE: 7514 Energetic particles (2114)
DE: 7519 Flares
DE: 7594 Instruments and techniques
SC: SPA-Solar and Heliospheric Physics [SH]
MN: 2007 Fall Meeting