@Article{HajraTsuEchGonSan:2015:ReE>0.,
author = "Hajra, Rajkumar and Tsurutani, Bruce T. and Echer, Ezequiel and
Gonzalez Alarcon, Walter Dem{\'e}trio and Santolik, Ondrei",
affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and {} and
{Instituto Nacional de Pesquisas Espaciais (INPE)} and {Instituto
Nacional de Pesquisas Espaciais (INPE)}",
title = "Relativistic (E> 0.6, > 2.0, and > 4.0 MeV) elelctron acceleration
at geosynchronous orbit during high-intensity, long-duration,
continuous AE activity (HILDCAA) events",
journal = "Astrophysical Journal",
year = "2015",
volume = "799",
number = "1",
keywords = "acceleration of particles, magnetic reconnection, relativistic
processes, solar wind, waves.",
abstract = "Radiation-belt relativistic (E > 0.6, > 2.0, and > 4.0 MeV)
electron acceleration is studied for solar cycle 23 (1995-2008).
High-intensity, long-duration, continuous AE activity (HILDCAA)
events are considered as the basis of the analyses. All of the 35
HILDCAA events under study were found to be characterized by flux
enhancements of magnetospheric relativistic electrons of all three
energies compared to the pre-event flux levels. For the E > 2.0
MeV electron fluxes, enhancement of > 50% occurred during 100% of
HILDCAAs. Cluster-4 passes were examined for electromagnetic
chorus waves in the 5 < L < 10 and 0 < MLT < 12 region when wave
data were available. Fully 100% of these HILDCAA cases were
associated with enhanced whistler-mode chorus waves. The
enhancements of E > 0.6, > 2.0, and > 4.0 MeV electrons occurred
similar to 1.0 day, similar to 1.5 days, and similar to 2.5 days
after the statistical HILDCAA onset, respectively. The statistical
acceleration rates for the three energy ranges were similar to 1.8
x 10(5), 2.2 x 10(3), and 1.0 x 10(1) cm(-2) s(-1) sr(-1) d(-1),
respectively. The relativistic electron-decay timescales were
determined to be similar to 7.7, 5.5, and 4.0 days for the three
energy ranges, respectively. The HILDCAAs were divided into
short-duration (D <= 3 days) and long-duration (D > 3 days) events
to study the dependence of relativistic electron variation on
HILDCAA duration. For long-duration events, the flux enhancements
during HILDCAAs with respect to pre-event fluxes were similar to
290%, 520%, and 82% for E > 0.6, > 2.0, and > 4.0 MeV electrons,
respectively. The enhancements were similar to 250%, 400%, and 27%
respectively, for short-duration events. The results are discussed
with respect to the current understanding of radiation-belt
dynamics.",
doi = "10.1088/0004-637X/799/1/39",
url = "http://dx.doi.org/10.1088/0004-637X/799/1/39",
issn = "0004-637X and 1538-4357",
language = "en",
targetfile = "Hajra_relativistic.pdf",
urlaccessdate = "27 abr. 2024"
}