SM21A-2512
Evolution of relativistic electron phase space density related to in-situ acceleration observed by Van Allen Probes
Tuesday, 15 December 2015
Poster Hall (Moscone South)
Si Liu1, Fuliang Xiao1, Chang Yang1, Yihua He1, Qinghua Zhou1, Harlan E. Spence2, Geoffrey D Reeves3, Herbert O Funsten4, J Bernard Blake5, Daniel N. Baker6 and John R Wygant7, (1)Changsha University of Science and Technology, Changsha, China, (2)University of New Hampshire Main Campus, Space Science Center, Durham, NH, United States, (3)Los Alamos National Laboratory, Los Alamos, NM, United States, (4)Los Alamos Natl Laboratory, Los Alamos, NM, United States, (5)Aerospace Corporation Santa Monica, Santa Monica, CA, United States, (6)University of Colorado at Boulder, Boulder, CO, United States, (7)University of Minnesota Twin Cities, Minneapolis, MN, United States
Abstract:
The radial phase space density (PSD) profiles in adiabatic invariant coordinate can be used to distinguish between local acceleration and radial transport. Resonant interaction with chorus waves plays an important role in situ acceleration. In this paper, we study the simultaneous data of chorus waves and energetic electrons fluxes during the storm 19 to 21 February 2014. The Van Allen Probes observed substantial enhancements in fluxes of energetic (53.8-108.3 keV) and relativistic (2-3.6 MeV) electrons. Chorus waves were excited at location L=4-6 after the fluxes of energetic electrons were greatly enhanced in the recovery phase. We calculate the PSD ( =3433 MeV/G) as a function of time and L* for =0.11 REG1/2. We find that the peak in radial PSD profile occurs in the vicinity of L*=4.5, characteristic of local acceleration. The results provide a further evidence for in-situ electron acceleration caused by whistler mode chorus waves in the outer radiation belts.
