HR: 14:15h
AN: SH33A-04    [Abstracts]
TI: Composition and Ionic Charge State Measurements of the Large Solar Particle Event of 20 January 2005
AU: * Labrador, A W
EM: labrador@srl.caltech.edu
AF: California Institute of Technology, 1201 E. California Blvd. Mail Code 220-47, Pasadena, CA 91125 United States
AU: Cohen, C M
AF: California Institute of Technology, 1201 E. California Blvd. Mail Code 220-47, Pasadena, CA 91125 United States
AU: Leske, R A
AF: California Institute of Technology, 1201 E. California Blvd. Mail Code 220-47, Pasadena, CA 91125 United States
AU: Mewaldt, R A
AF: California Institute of Technology, 1201 E. California Blvd. Mail Code 220-47, Pasadena, CA 91125 United States
AU: Stone, E C
AF: California Institute of Technology, 1201 E. California Blvd. Mail Code 220-47, Pasadena, CA 91125 United States
AU: Wiedenbeck, M E
AF: Jet Propulsion Laboratory, MS 169-327 4800 Oak Grove Dr., Pasadena, CA 91109 United States
AU: Mason, G M
AF: University of Maryland, Dept. of Physics, College Park, MD 20742 United States
AU: Desai, M I
AF: University of Maryland, Dept. of Physics, College Park, MD 20742 United States
AU: von Rosenvinge, T T
AF: NASA Goddard Space Flight Center, MC 661, Greenbelt, MD 20771 United States
AU: Looper, M D
AF: The Aerospace Corporation, P.O. Box 92957, Los Angeles, CA 90009 United States
AU: Mazur, J E
AF: The Aerospace Corporation, P.O. Box 92957, Los Angeles, CA 90009 United States
AU: Selesnick, R S
AF: The Aerospace Corporation, P.O. Box 92957, Los Angeles, CA 90009 United States
AU: Haggerty, D K
AF: Johns Hopkins University, Applied Physics Lab MP3-E184 11100 Johns Hopkins Rd., Laurel, MD 20723 United States
AB: The 20 January 2005 solar event was observed as a large ground-level event by neutron monitors and as a large solar energetic particle event by spacecraft, with particle spectra comparable to the hardest events of solar cycle 23. We will present composition and ionic charge state measurements for this event using data from instruments aboard the ACE and SAMPEX spacecraft. These results will include species from H to Fe spanning the energy range from ~0.1 to ~300 MeV/nuc. A new analysis of penetrating particles has been used to extend the ACE/SIS heavy-ion spectra to higher energies (e.g. up to 300 MeV/nuc) in order to investigate the possibility of high-energy spectral rollovers. The charge state measurements have been obtained from SAMPEX data, using the geomagnetic rigidity-filter technique in the energy range from ~30 to ~90 MeV/nuc. We will compare the composition and charge state measurements for this event with measurements of other large events from the past solar cycle, including possible correlations between the elemental and ionic charge state composition.
DE: 7500 SOLAR PHYSICS, ASTROPHYSICS, AND ASTRONOMY
DE: 7513 Coronal mass ejections
DE: 7514 Energetic particles (2114)
SC: SPA-Solar and Heliospheric Physics [SH]
MN: 2005 Joint Assembly