TY  - JOUR
A1  - Kronberg, Elena A.
A1  - Rashev, M. V.
A1  - Daly, P. W.
A1  - Shprits, Yuri Y.
A1  - Turner, D. L.
A1  - Drozdov, Alexander
A1  - Dobynde, M.
A1  - Kellerman, Adam C.
A1  - Fritz, T. A.
A1  - Pierrard, V.
A1  - Borremans, K.
A1  - Klecker, B.
A1  - Friedel, R.
T1  - Contamination in electron observations of the silicon detector on board
JF  - Space Weather: The International Journal of Research and Applications
N2  - Since more than 15 years, the Cluster mission passes through Earth's radiation belts at least once every 2 days for several hours, measuring the electron intensity at energies from 30 to 400 keV. These data have previously been considered not usable due to contamination caused by penetrating energetic particles (protons at >100 keV and electrons at >400 keV). In this study, we assess the level of distortion of energetic electron spectra from the Research with Adaptive Particle Imaging Detector (RAPID)/Imaging Electron Spectrometer (IES) detector, determining the efficiency of its shielding. We base our assessment on the analysis of experimental data and a radiation transport code (Geant4). In simulations, we use the incident particle energy distribution of the AE9/AP9 radiation belt models. We identify the Roederer L values, L⋆, and energy channels that should be used with caution: at 3≤L⋆≤4, all energy channels (40–400 keV) are contaminated by protons (≃230 to 630 keV and >600 MeV); at L⋆≃1 and 4–6, the energy channels at 95–400 keV are contaminated by high-energy electrons (>400 keV). Comparison of the data with electron and proton observations from RBSP/MagEIS indicates that the subtraction of proton fluxes at energies ≃ 230–630 keV from the IES electron data adequately removes the proton contamination. We demonstrate the usefulness of the corrected data for scientific applications.
Y1  - 2016
U6  - https://doi.org/10.1002/2016SW001369
SN  - 1542-7390
VL  - 14
SP  - 449
EP  - 462
PB  - American Geophysical Union
CY  - Washington
ER  - 
TY  - JOUR
A1  - Boyd, A. J.
A1  - Spence, Harlan E.
A1  - Huang, Chia-Lin
A1  - Reeves, Geoffrey D.
A1  - Baker, Daniel N.
A1  - Turner, D. L.
A1  - Claudepierre, Seth G.
A1  - Fennell, Joseph F.
A1  - Blake, J. Bernard
A1  - Shprits, Yuri Y.
T1  - Statistical properties of the radiation belt seed population
JF  - Journal of geophysical research : Space physics
N2  - We present a statistical analysis of phase space density data from the first 26 months of the Van Allen Probes mission. In particular, we investigate the relationship between the tens and hundreds of keV seed electrons and >1 MeV core radiation belt electron population. Using a cross-correlation analysis, we find that the seed and core populations are well correlated with a coefficient of approximate to 0.73 with a time lag of 10-15 h. We present evidence of a seed population threshold that is necessary for subsequent acceleration. The depth of penetration of the seed population determines the inner boundary of the acceleration process. However, we show that an enhanced seed population alone is not enough to produce acceleration in the higher energies, implying that the seed population of hundreds of keV electrons is only one of several conditions required for MeV electron radiation belt acceleration.
Y1  - 2016
U6  - https://doi.org/10.1002/2016JA022652
SN  - 2169-9380
SN  - 2169-9402
VL  - 121
SP  - 7636
EP  - 7646
PB  - American Geophysical Union
CY  - Washington
ER  -