Observation of space radiation environment with EXOS-D

Takagi, Shohei; Nakamura, Tomoki; Kohno, Toshitake; Shiono, Noboru; Makino, Fumiaki

doi:10.1109/23.273513

Cited by 33 publications

(25 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The data for whistler mode waves were obtained by the VLF instrument of the Akebono satellite [Kimura et al, 1990]. The relativistic electrons were obtained from GOES satellites at GEO and from the Radiation Monitor of the Akebono satellite [Takagi et al, 1993]. Data on the thermal plasma density, hot electrons, and whistler mode waves were averaged over the dawn side (0-12 MLT).…”

Section: Discussionmentioning

confidence: 99%

High‐speed solar wind with southward interplanetary magnetic field causes relativistic electron flux enhancement of the outer radiation belt via enhanced condition of whistler waves

Miyoshi

Kataoka

Kasahara

et al. 2013

Geophysical Research Letters

132

163

View full text Add to dashboard Cite

Relativistic electron flux in the outer radiation belt tends to increase during the high‐speed solar wind stream (HSS) events. However, HSS events do not always cause large flux enhancement. To determine the HSS events that cause such enhancement and the mechanisms that are responsible for accelerating the electrons, we analyzed long‐term plasma data sets, for periods longer than one solar cycle. We demonstrate that during HSS events with the southward interplanetary magnetic field (IMF)‐dominant HSS (SBz‐HSS), relativistic electrons are accelerated by whistler mode waves; however, during HSS events with the northward IMF‐dominant HSS, this acceleration mechanism is not effective. The differences in the responses of the outer radiation belt flux variations are caused by the differences in the whistler mode wave–electron interactions associated with a series of substorms. During SBz‐HSS events, hot electron injections occur and the thermal plasma density decreases due to the shrinkage of the plasmapause, causing large flux enhancement of relativistic electrons through whistler mode wave excitation. These results explain why large flux enhancement of relativistic electrons tends to occur during SBz‐HSS events.

show abstract

Section: Discussionmentioning

confidence: 99%

High‐speed solar wind with southward interplanetary magnetic field causes relativistic electron flux enhancement of the outer radiation belt via enhanced condition of whistler waves

Miyoshi

Kataoka

Kasahara

et al. 2013

Geophysical Research Letters

132

163

View full text Add to dashboard Cite

show abstract

“…The Akebono satellite observed enhancements of radiation belt electrons during the active period on 3À 5 September 2008. Akebono was launched in February 1989 by the Institute of Space and Astronautical Science in Japan (Takagi et al, 1993). In September 2008, Akebono was in a high inclination, highly elliptical orbit with apogee at 5260 km altitude, perigee altitude at 295 km, and orbit period of 2.5 h. The Radiation Monitor (RDM) measured electron fluxes in three energy channels: 0.30-0.95 MeV, 0.95-2.5 MeV and42.5 MeV (Takagi et al, 1993).…”

Section: Rbe Simulation Of a Mhd Substormmentioning

confidence: 99%

Recent developments in the radiation belt environment model

Fok

Glocer

Zheng

et al. 2011

Journal of Atmospheric and Solar-Terrestrial Physics

View full text Add to dashboard Cite

a b s t r a c tThe fluxes of energetic particles in the radiation belts are found to be strongly controlled by the solar wind conditions. In order to understand and predict the radiation particle intensities, we have developed a physics-based Radiation Belt Environment (RBE) model that considers the influences from the solar wind, ring current and plasmasphere. Recently, an improved calculation of wave-particle interactions has been incorporated. In particular, the model now includes cross diffusion in energy and pitch-angle. We find that the exclusion of cross diffusion could cause significant overestimation of electron flux enhancement during storm recovery. The RBE model is also connected to MHD fields so that the response of the radiation belts to fast variations in the global magnetosphere can be studied. We are able to reproduce the rapid flux increase during a substorm dipolarization on 4 September 2008. The timing is much shorter than the time scale of wave associated acceleration.Published by Elsevier Ltd.

show abstract

“…Three energetic electron channels used in this study were E1 (0.3 < E < 0.95 MeV), E2 (0.95 < E < 2.5 MeV), and E3 (E > 2.5 MeV). The contamination of energetic protons to the electron channels was estimated to be negligibly small (Takagi et al, 1993 …”

Section: Observationsmentioning

confidence: 99%

“…The RDM (Radiation Monitor) system onboard the satellite had four solid state detectors which enabled it to detect energetic electrons, protons and alpha particles with the time resolution of 8 sec (Takagi et al, 1993). Three energetic electron channels used in this study were E1 (0.3 < E < 0.95 MeV), E2 (0.95 < E < 2.5 MeV), and E3 (E > 2.5 MeV).…”

Section: Observationsmentioning

confidence: 99%

Pitch angle distribution of relativistic electrons in the inner radiation belt and its relation to equatorial plasma wave turbulence phenomena

Morioka¹,

Misawa²,

Miyoshi³

et al. 2001

Geophysical Research Letters

View full text Add to dashboard Cite

Abstract. The pitch angie distribution of relativistic electrons in the inner radiation belt and its relation to local plasma waves were investigated using the data from the Akebono satellite. It was found that energetic electrons (> i MeV) in the inner radiation belt showed an unexpected dumbbell distribution near the magnetic equator. This feature was commonly observed both in magnetically disturbed and undisturbed conditions. It was also found that this anomalous pitch angle distribution of energetic electrons was always accompanied with the enhancement of local UHR waves around the magnetic equator. These newly found features indicate the existence of an unknown waveparticle interaction process between the relativistic electrons and quasi-electrostatic plasma waves in the equatorial region of the plasmasphere.

show abstract

Observation of space radiation environment with EXOS-D

Cited by 33 publications

References 4 publications

High‐speed solar wind with southward interplanetary magnetic field causes relativistic electron flux enhancement of the outer radiation belt via enhanced condition of whistler waves

High‐speed solar wind with southward interplanetary magnetic field causes relativistic electron flux enhancement of the outer radiation belt via enhanced condition of whistler waves

Recent developments in the radiation belt environment model

Pitch angle distribution of relativistic electrons in the inner radiation belt and its relation to equatorial plasma wave turbulence phenomena

Contact Info

Product

Resources

About