SM41D-2509
Variability of the Inner Proton Radiation Belt Observed by Van Allen Probes
Thursday, 17 December 2015
Poster Hall (Moscone South)
Richard Selesnick1, Xinlin Li2, Daniel N. Baker3, Allison N Jaynes4, Shrikanth G Kanekal5, Mary K Hudson6 and Brian T Kress6, (1)Kirtland Air Force Base, Kirtland AFB, NM, United States, (2)Univ Colorado at Boulder, Boulder, CO, United States, (3)University of Colorado at Boulder, Boulder, CO, United States, (4)University of Colorado at Boulder, LASP, Boulder, CO, United States, (5)NASA Goddard Space Flight Center, Greenbelt, MD, United States, (6)Dartmouth College, Hanover, NH, United States
Abstract:
Inner radiation belt protons with kinetic energy above 10 MeV are known to be highly stable, with a maximum intensity near L = 1.5 that varies little evenon solar-cycle time scales. However, for L = 2 and above, more rapid changes occur: (1) protons are trapped during solar particle events, (2) steady intensity changes near L = 2 may result from radial diffusion, (3) for L > 2 there are rapid losses during magnetic storms, and (4) the losses are replenished by albedo neutron decay. New measurements from Van Allen Probes describe each of the last three processes in detail (the first has not yet been observed). These data provide new constraints on theories of trapped proton dynamics and improved empirical estimates of transport coefficients for radiation belt modeling.
