TY  - JOUR
A1  - Smirnov, Artem G.
A1  - Kronberg, Elena A.
A1  - Latallerie, F.
A1  - Daly, Patrick W.
A1  - Aseev, Nikita
A1  - Shprits, Yuri Y.
A1  - Kellerman, Adam C.
A1  - Kasahara, Satoshi
A1  - Turner, Drew L.
A1  - Taylor, M. G. G. T.
T1  - Electron Intensity Measurements by the Cluster/RAPID/IES Instrument in Earth's Radiation Belts and Ring Current
JF  - Space Weather: The International Journal of Research and Applications
N2  - Plain Language Summary Radiation belts of the Earth, which are the zones of charged energetic particles trapped by the geomagnetic field, comprise enormous and dynamic systems. While the inner radiation belt, composed mainly of high-energy protons, is relatively stable, the outer belt, filled with energetic electrons, is highly variable and depends substantially on solar activity. Hence, extended reliable observations and the improved models of the electron intensities in the outer belt depending on solar wind parameters are necessary for prediction of their dynamics. The Cluster mission has been measuring electron flux intensities in the radiation belts since its launch in 2000, thus providing a huge dataset that can be used for radiation belts analysis. Using 16 years of electron measurements by the Cluster mission corrected for background contamination, we derived a uniform linear-logarithmic dependence of electron fluxes in the outer belt on the solar wind dynamic pressure.
Y1  - 2019
U6  - https://doi.org/10.1029/2018SW001989
SN  - 1542-7390
VL  - 17
IS  - 4
SP  - 553
EP  - 566
PB  - American Geophysical Union
CY  - Washington
ER  - 
TY  - JOUR
A1  - Drozdov, Alexander
A1  - Aseev, Nikita
A1  - Effenberger, Frederic
A1  - Turner, Drew L.
A1  - Saikin, Anthony
A1  - Shprits, Yuri Y.
T1  - Storm Time Depletions of Multi-MeV Radiation Belt Electrons Observed at Different Pitch Angles
JF  - Journal of geophysical research : Space physics
N2  - During geomagnetic storms, the rapid depletion of the high-energy (several MeV) outer radiation belt electrons is the result of loss to the interplanetary medium through the magnetopause, outward radial diffusion, and loss to the atmosphere due to wave-particle interactions. We have performed a statistical study of 110 storms using pitch angle resolved electron flux measurements from the Van Allen Probes mission and found that inside of the radiation belt (L* = 3 - 5) the number of storms that result in depletion of electrons with equatorial pitch angle alpha(eq) = 30 degrees is higher than number of storms that result in depletion of electrons with equatorial pitch angle alpha(eq) = 75 degrees. We conclude that this result is consistent with electron scattering by whistler and electromagnetic ion cyclotron waves. At the outer edge of the radiation belt (L* >= 5.2) the number of storms that result in depletion is also large (similar to 40-50%), emphasizing the significance of the magnetopause shadowing effect and outward radial transport.
Y1  - 2019
U6  - https://doi.org/10.1029/2019JA027332
SN  - 2169-9380
SN  - 2169-9402
VL  - 124
IS  - 11
SP  - 8943
EP  - 8953
PB  - American Geophysical Union
CY  - Washington
ER  - 
TY  - JOUR
A1  - Ripoll, Jean-Francois
A1  - Loridan, Vivien
A1  - Denton, Michael H.
A1  - Cunningham, Gregory
A1  - Reeves, G.
A1  - Santolik, O.
A1  - Fennell, Joseph
A1  - Turner, Drew L.
A1  - Drozdov, Alexander
A1  - Cervantes Villa, Juan Sebastian
A1  - Shprits, Yuri Y.
A1  - Thaller, Scott A.
A1  - Kurth, William S.
A1  - Kletzing, Craig A.
A1  - Henderson, Michael  G.
A1  - Ukhorskiy, Aleksandr Y.
T1  - Observations and Fokker-Planck Simulations of the L-Shell, Energy, and Times
JF  - Journal of geophysical research : Space physics
N2  - The evolution of the radiation belts in L-shell (L), energy (E), and equatorial pitch angle (alpha(0)) is analyzed during the calm 11-day interval (4-15 March) following the 1 March 2013 storm. Magnetic Electron and Ion Spectrometer (MagEIS) observations from Van Allen Probes are interpreted alongside 1D and 3D Fokker-Planck simulations combined with consistent event-driven scattering modeling from whistler mode hiss waves. Three (L, E, alpha(0)) regions persist through 11 days of hiss wave scattering; the pitch angle-dependent inner belt core (L similar to <2.2 and E < 700 keV), pitch angle homogeneous outer belt low-energy core (L > similar to 5 and E similar to < 100 keV), and a distinct pocket of electrons (L similar to [4.5, 5.5] and E similar to [0.7, 2] MeV). The pitch angle homogeneous outer belt is explained by the diffusion coefficients that are roughly constant for alpha(0) similar to <60 degrees, E > 100 keV, 3.5 < L < L-pp similar to 6. Thus, observed unidirectional flux decays can be used to estimate local pitch angle diffusion rates in that region. Top-hat distributions are computed and observed at L similar to 3-3.5 and E = 100-300 keV.
KW  - radiation belts
KW  - wave-particle interactions
KW  - electron lifetime
KW  - pitch angle diffusion coefficient
KW  - hiss waves
Y1  - 2018
U6  - https://doi.org/10.1029/2018JA026111
SN  - 2169-9380
SN  - 2169-9402
VL  - 124
IS  - 2
SP  - 1125
EP  - 1142
PB  - American Geophysical Union
CY  - Washington
ER  -