HR: 08:40h
AN: SH21A-03    [Abstracts]
TI: Neutron Monitor Observations of the January 20, 2005 Ground Level Enhancement
AU: * Bieber, J W
EM: john@bartol.udel.edu
AF: University of Delaware, Bartol Research Institute, Department of Physics and Astronomy, Newark, DE 19716 United States
AU: Clem, J
EM: clem@bartol.udel.edu
AF: University of Delaware, Bartol Research Institute, Department of Physics and Astronomy, Newark, DE 19716 United States
AU: Evenson, P
EM: penguin@bartol.udel.edu
AF: University of Delaware, Bartol Research Institute, Department of Physics and Astronomy, Newark, DE 19716 United States
AU: Pyle, R
EM: pyle@bartol.udel.edu
AF: University of Delaware, Bartol Research Institute, Department of Physics and Astronomy, Newark, DE 19716 United States
AU: Ruffolo, D
EM: david_ruffolo@yahoo.com
AF: Mahidol University, Department of Physics, Faculty of Science, Bangkok, 10400 Thailand
AU: Rujiwarodom, M
EM: rmanit@sc.chula.ac.th
AF: Chulalongkorn University, Department of Physics, Faculty of Science, Bangkok, 10330 Thailand
AU: Saiz, A
EM: alex@astro.phys.sc.chula.ac.th
AF: Mahidol University, Department of Physics, Faculty of Science, Bangkok, 10400 Thailand
AU: Saiz, A
EM: alex@astro.phys.sc.chula.ac.th
AF: Chulalongkorn University, Department of Physics, Faculty of Science, Bangkok, 10330 Thailand
AU: Duldig, M
EM: Marc.Duldig@aad.gov.au
AF: Australian Antarctic Division, Australian Antarctic Division, Kingston, Tasmania, 7050 Australia
AU: Humble, J
EM: john.humble@utas.edu.au
AF: University of Tasmania, School of Mathematics and Physics, Hobart, Tasmania, 7001 Australia
AB: Within a 6-minute span on January 20, 2005, the count rate of the high-altitude neutron monitor at South Pole increased by a factor of 56. This was the largest increase of cosmic radiation ever recorded on the surface of Earth. Normalized to sea level, the event was second only to the famous 1956 ground level enhancement. The event was enormously anisotropic, as high-latitude stations outside Antarctica recorded an increase roughly a factor of 10 smaller. We employ observations from the Spaceship Earth network and other neutron monitors to derive the time profile, anisotropy, and energy spectrum of relativistic solar protons on January 20, 2005. We also model the event based upon the Boltzmann equation and conclude that this event may have featured a rare instance of wave excitation and nonlinear transport from streaming relativistic protons. Supported by NSF grant ATM-0000315, by the Thailand Research Fund, and by the Rachadapisek Sompoj Fund of Chulalongkorn University.
UR: http://neutronm.bartol.udel.edu/
DE: 2104 Cosmic rays
DE: 2114 Energetic particles (7514)
DE: 7845 Particle acceleration
DE: 7984 Space radiation environment
SC: SPA-Solar and Heliospheric Physics [SH]
MN: Fall Meeting 2005