Articles | Volume 39, issue 3
https://doi.org/10.5194/angeo-39-413-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/angeo-39-413-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
On the semi-annual variation of relativistic electrons in the outer radiation belt
Christos Katsavrias
CORRESPONDING AUTHOR
Department of Physics, National and Kapodistrian University of Athens, Athens, Greece
Space Applications and Research Consultancy (SPARC), Athens, Greece
Constantinos Papadimitriou
Department of Physics, National and Kapodistrian University of Athens, Athens, Greece
Space Applications and Research Consultancy (SPARC), Athens, Greece
Sigiava Aminalragia-Giamini
Department of Physics, National and Kapodistrian University of Athens, Athens, Greece
Space Applications and Research Consultancy (SPARC), Athens, Greece
Ioannis A. Daglis
Department of Physics, National and Kapodistrian University of Athens, Athens, Greece
Hellenic Space Center, Athens, Greece
Ingmar Sandberg
Space Applications and Research Consultancy (SPARC), Athens, Greece
Piers Jiggens
ESA/ESTEC, Noordwijk, the Netherlands
Related authors
Nour Dahmen, Antoine Brunet, Sebastien Bourdarie, Christos Katsavrias, Guillerme Bernoux, Stefanos Doulfis, Afroditi Nasi, Ingmar Sandberg, Constantinos Papadimitriou, Jesus Oliveros Fernandez, and Ioannis Daglis
Ann. Geophys., 41, 301–312, https://doi.org/10.5194/angeo-41-301-2023, https://doi.org/10.5194/angeo-41-301-2023, 2023
Short summary
Short summary
Earth’s space environment is populated with charged particles. The energetic ones are trapped around Earth in radiation belts. Orbiting spacecraft that cross their region can accumulate charges on their internal surfaces, leading to hazardous electrostatic discharges. This paper showcases the SafeSpace safety prototype, which aims to warn satellite operators of probable incoming hazardous events by simulating the dynamics of the electron radiation belts from their origin at the Sun.
Christos Katsavrias, Afroditi Nasi, Ioannis A. Daglis, Sigiava Aminalragia-Giamini, Nourallah Dahmen, Constantinos Papadimitriou, Marina Georgiou, Antoine Brunet, and Sebastien Bourdarie
Ann. Geophys., 40, 379–393, https://doi.org/10.5194/angeo-40-379-2022, https://doi.org/10.5194/angeo-40-379-2022, 2022
Short summary
Short summary
The radial diffusion mechanism is of utmost importance to both the acceleration and loss of relativistic electrons in the outer radiation belt and, consequently, for physics-based models, which provide nowcasting and forecasting of the electron population. In the framework of the "SafeSpace" project, we have created a database of calculated radial diffusion coefficients, and, furthermore, we have exploited it to provide insights for future modelling efforts.
C. Tsironis, A. Anastasiadis, C. Katsavrias, and I. A. Daglis
Ann. Geophys., 34, 171–185, https://doi.org/10.5194/angeo-34-171-2016, https://doi.org/10.5194/angeo-34-171-2016, 2016
M. Georgiou, I. A. Daglis, E. Zesta, G. Balasis, I. R. Mann, C. Katsavrias, and K. Tsinganos
Ann. Geophys., 33, 1431–1442, https://doi.org/10.5194/angeo-33-1431-2015, https://doi.org/10.5194/angeo-33-1431-2015, 2015
Short summary
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Our study demonstrates a remarkable association between the earthward penetration of ULF waves and radiation belt electron enhancements during four magnetic storms that occurred in 2001. In the past, ULF waves had been observed at unusual depths during rare superstorms. But ULF wave activity, reaching magnetic shells as low as 2, was also observed during relatively intense storms when it played a key role in diffusing electrons radially inward and thereby accelerating them to higher energies.
C. Katsavrias, I. A. Daglis, W. Li, S. Dimitrakoudis, M. Georgiou, D. L. Turner, and C. Papadimitriou
Ann. Geophys., 33, 1173–1181, https://doi.org/10.5194/angeo-33-1173-2015, https://doi.org/10.5194/angeo-33-1173-2015, 2015
Nour Dahmen, Antoine Brunet, Sebastien Bourdarie, Christos Katsavrias, Guillerme Bernoux, Stefanos Doulfis, Afroditi Nasi, Ingmar Sandberg, Constantinos Papadimitriou, Jesus Oliveros Fernandez, and Ioannis Daglis
Ann. Geophys., 41, 301–312, https://doi.org/10.5194/angeo-41-301-2023, https://doi.org/10.5194/angeo-41-301-2023, 2023
Short summary
Short summary
Earth’s space environment is populated with charged particles. The energetic ones are trapped around Earth in radiation belts. Orbiting spacecraft that cross their region can accumulate charges on their internal surfaces, leading to hazardous electrostatic discharges. This paper showcases the SafeSpace safety prototype, which aims to warn satellite operators of probable incoming hazardous events by simulating the dynamics of the electron radiation belts from their origin at the Sun.
Christos Katsavrias, Afroditi Nasi, Ioannis A. Daglis, Sigiava Aminalragia-Giamini, Nourallah Dahmen, Constantinos Papadimitriou, Marina Georgiou, Antoine Brunet, and Sebastien Bourdarie
Ann. Geophys., 40, 379–393, https://doi.org/10.5194/angeo-40-379-2022, https://doi.org/10.5194/angeo-40-379-2022, 2022
Short summary
Short summary
The radial diffusion mechanism is of utmost importance to both the acceleration and loss of relativistic electrons in the outer radiation belt and, consequently, for physics-based models, which provide nowcasting and forecasting of the electron population. In the framework of the "SafeSpace" project, we have created a database of calculated radial diffusion coefficients, and, furthermore, we have exploited it to provide insights for future modelling efforts.
Ioannis A. Daglis, Loren C. Chang, Sergio Dasso, Nat Gopalswamy, Olga V. Khabarova, Emilia Kilpua, Ramon Lopez, Daniel Marsh, Katja Matthes, Dibyendu Nandy, Annika Seppälä, Kazuo Shiokawa, Rémi Thiéblemont, and Qiugang Zong
Ann. Geophys., 39, 1013–1035, https://doi.org/10.5194/angeo-39-1013-2021, https://doi.org/10.5194/angeo-39-1013-2021, 2021
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We present a detailed account of the science programme PRESTO (PREdictability of the variable Solar–Terrestrial cOupling), covering the period 2020 to 2024. PRESTO was defined by a dedicated committee established by SCOSTEP (Scientific Committee on Solar-Terrestrial Physics). We review the current state of the art and discuss future studies required for the most effective development of solar–terrestrial physics.
Constantinos Papadimitriou, Georgios Balasis, Ioannis A. Daglis, and Omiros Giannakis
Ann. Geophys., 36, 287–299, https://doi.org/10.5194/angeo-36-287-2018, https://doi.org/10.5194/angeo-36-287-2018, 2018
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Swarm is the fourth Earth Explorer mission of the European Space Agency (ESA), launched on 23 November 2013. The mission provides an opportunity for better knowledge of the near-Earth electromagnetic environment. This study presents an initial attempt to derive an ultra low-frequency (ULF) wave index from low-Earth orbit satellite data. The technique can be potentially used to define a new product from the mission, the Swarm ULF wave index, which would be suitable for space weather applications.
C. Tsironis, A. Anastasiadis, C. Katsavrias, and I. A. Daglis
Ann. Geophys., 34, 171–185, https://doi.org/10.5194/angeo-34-171-2016, https://doi.org/10.5194/angeo-34-171-2016, 2016
M. Georgiou, I. A. Daglis, E. Zesta, G. Balasis, I. R. Mann, C. Katsavrias, and K. Tsinganos
Ann. Geophys., 33, 1431–1442, https://doi.org/10.5194/angeo-33-1431-2015, https://doi.org/10.5194/angeo-33-1431-2015, 2015
Short summary
Short summary
Our study demonstrates a remarkable association between the earthward penetration of ULF waves and radiation belt electron enhancements during four magnetic storms that occurred in 2001. In the past, ULF waves had been observed at unusual depths during rare superstorms. But ULF wave activity, reaching magnetic shells as low as 2, was also observed during relatively intense storms when it played a key role in diffusing electrons radially inward and thereby accelerating them to higher energies.
N. Y. Ganushkina, M. W. Liemohn, S. Dubyagin, I. A. Daglis, I. Dandouras, D. L. De Zeeuw, Y. Ebihara, R. Ilie, R. Katus, M. Kubyshkina, S. E. Milan, S. Ohtani, N. Ostgaard, J. P. Reistad, P. Tenfjord, F. Toffoletto, S. Zaharia, and O. Amariutei
Ann. Geophys., 33, 1369–1402, https://doi.org/10.5194/angeo-33-1369-2015, https://doi.org/10.5194/angeo-33-1369-2015, 2015
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A number of current systems exist in the Earth's magnetosphere. It is very difficult to identify local measurements as belonging to a specific current system. Therefore, there are different definitions of supposedly the same current, leading to unnecessary controversy. This study presents a robust collection of these definitions of current systems in geospace, particularly in the near-Earth nightside magnetosphere, as viewed from a variety of observational and computational analysis techniques.
G. Balasis, I. A. Daglis, I. R. Mann, C. Papadimitriou, E. Zesta, M. Georgiou, R. Haagmans, and K. Tsinganos
Ann. Geophys., 33, 1237–1252, https://doi.org/10.5194/angeo-33-1237-2015, https://doi.org/10.5194/angeo-33-1237-2015, 2015
C. Katsavrias, I. A. Daglis, W. Li, S. Dimitrakoudis, M. Georgiou, D. L. Turner, and C. Papadimitriou
Ann. Geophys., 33, 1173–1181, https://doi.org/10.5194/angeo-33-1173-2015, https://doi.org/10.5194/angeo-33-1173-2015, 2015
T. M. Giannaros, D. Melas, I. A. Daglis, and I. Keramitsoglou
Nat. Hazards Earth Syst. Sci., 14, 347–358, https://doi.org/10.5194/nhess-14-347-2014, https://doi.org/10.5194/nhess-14-347-2014, 2014
Related subject area
Subject: Magnetosphere & space plasma physics | Keywords: Radiation belts
Comparison of radiation belt electron fluxes simultaneously measured with PROBA-V/EPT and RBSP/MagEIS instruments
Electron radiation belt safety indices based on the SafeSpace modelling pipeline and dedicated to the internal charging risk
The “SafeSpace” database of ULF power spectral density and radial diffusion coefficients: dependencies and application to simulations
Quantifying the non-linear dependence of energetic electron fluxes in the Earth's radiation belts with radial diffusion drivers
Seasonal dependence of the Earth's radiation belt – new insights
Distribution of Earth's radiation belts' protons over the drift frequency of particles
Outer Van Allen belt trapped and precipitating electron flux responses to two interplanetary magnetic clouds of opposite polarity
Outer radiation belt and inner magnetospheric response to sheath regions of coronal mass ejections: a statistical analysis
Energetic electron enhancements under the radiation belt (L < 1.2) during a non-storm interval on 1 August 2008
GREEN: the new Global Radiation Earth ENvironment model (beta version)
Van Allen Probes observation of plasmaspheric hiss modulated by injected energetic electrons
Alexandre Winant, Viviane Pierrard, and Edith Botek
Ann. Geophys., 41, 313–325, https://doi.org/10.5194/angeo-41-313-2023, https://doi.org/10.5194/angeo-41-313-2023, 2023
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In this work, we analyzed and compared measurements of electron fluxes in the radiation belts from two instruments with different orbits. In the outer belt, where the altitude difference is the largest between the two instruments, we find that the observations are in good agreement, except during geomagnetic storms, during which fluxes at low altitudes are much lower than at high altitudes. In general, both at low and high altitudes, the correlation between the instruments was found to be good.
Nour Dahmen, Antoine Brunet, Sebastien Bourdarie, Christos Katsavrias, Guillerme Bernoux, Stefanos Doulfis, Afroditi Nasi, Ingmar Sandberg, Constantinos Papadimitriou, Jesus Oliveros Fernandez, and Ioannis Daglis
Ann. Geophys., 41, 301–312, https://doi.org/10.5194/angeo-41-301-2023, https://doi.org/10.5194/angeo-41-301-2023, 2023
Short summary
Short summary
Earth’s space environment is populated with charged particles. The energetic ones are trapped around Earth in radiation belts. Orbiting spacecraft that cross their region can accumulate charges on their internal surfaces, leading to hazardous electrostatic discharges. This paper showcases the SafeSpace safety prototype, which aims to warn satellite operators of probable incoming hazardous events by simulating the dynamics of the electron radiation belts from their origin at the Sun.
Christos Katsavrias, Afroditi Nasi, Ioannis A. Daglis, Sigiava Aminalragia-Giamini, Nourallah Dahmen, Constantinos Papadimitriou, Marina Georgiou, Antoine Brunet, and Sebastien Bourdarie
Ann. Geophys., 40, 379–393, https://doi.org/10.5194/angeo-40-379-2022, https://doi.org/10.5194/angeo-40-379-2022, 2022
Short summary
Short summary
The radial diffusion mechanism is of utmost importance to both the acceleration and loss of relativistic electrons in the outer radiation belt and, consequently, for physics-based models, which provide nowcasting and forecasting of the electron population. In the framework of the "SafeSpace" project, we have created a database of calculated radial diffusion coefficients, and, furthermore, we have exploited it to provide insights for future modelling efforts.
Adnane Osmane, Mikko Savola, Emilia Kilpua, Hannu Koskinen, Joseph E. Borovsky, and Milla Kalliokoski
Ann. Geophys., 40, 37–53, https://doi.org/10.5194/angeo-40-37-2022, https://doi.org/10.5194/angeo-40-37-2022, 2022
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It has long been known that particles get accelerated close to the speed of light in the near-Earth space environment. Research in the last decades has also clarified what processes and waves are responsible for the acceleration of particles. However, it is difficult to quantify the scale of the impact of various processes competing with one another. In this study we present a methodology to quantify the impact waves can have on energetic particles.
Rajkumar Hajra
Ann. Geophys., 39, 181–187, https://doi.org/10.5194/angeo-39-181-2021, https://doi.org/10.5194/angeo-39-181-2021, 2021
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Geomagnetic activity is known to exhibit semi-annual variation with larger occurrences during equinoxes. A similar seasonal feature was reported for relativistic (∼ MeV) electrons throughout the entire outer zone radiation belt. Present work, for the first time reveals that electron fluxes increase with an ∼ 6-month periodicity in a limited L-shell only with large dependence in solar activity cycle. In addition, flux enhancements are not essentially equinoctial.
Alexander S. Kovtyukh
Ann. Geophys., 39, 171–179, https://doi.org/10.5194/angeo-39-171-2021, https://doi.org/10.5194/angeo-39-171-2021, 2021
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This is a continuation of work published in Annales Gephysicae between 2016 and 2020. In this paper, a new method for analyzing experimental data is proposed, calculations are carried out, and a new class of distributions of particles of radiation belts is constructed. As a result of this work, new, finer physical regularities of the structure of the Earth's proton radiation belt and its solar-cyclic variations have been obtained, which cannot be obtained by other methods.
Harriet George, Emilia Kilpua, Adnane Osmane, Timo Asikainen, Milla M. H. Kalliokoski, Craig J. Rodger, Stepan Dubyagin, and Minna Palmroth
Ann. Geophys., 38, 931–951, https://doi.org/10.5194/angeo-38-931-2020, https://doi.org/10.5194/angeo-38-931-2020, 2020
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We compared trapped outer radiation belt electron fluxes to high-latitude precipitating electron fluxes during two interplanetary coronal mass ejections (ICMEs) with opposite magnetic cloud rotation. The electron response had many similarities and differences between the two events, indicating that different acceleration mechanisms acted. Van Allen Probe data were used for trapped electron flux measurements, and Polar Operational Environmental Satellites were used for precipitating flux data.
Milla M. H. Kalliokoski, Emilia K. J. Kilpua, Adnane Osmane, Drew L. Turner, Allison N. Jaynes, Lucile Turc, Harriet George, and Minna Palmroth
Ann. Geophys., 38, 683–701, https://doi.org/10.5194/angeo-38-683-2020, https://doi.org/10.5194/angeo-38-683-2020, 2020
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We present a comprehensive statistical study of the response of the Earth's space environment in sheath regions prior to interplanetary coronal mass ejections. The inner magnetospheric wave activity is enhanced in sheath regions, and the sheaths cause significant changes to the outer radiation belt electron fluxes over short timescales. We also show that non-geoeffective sheaths can result in a significant response.
Alla V. Suvorova, Alexei V. Dmitriev, and Vladimir A. Parkhomov
Ann. Geophys., 37, 1223–1241, https://doi.org/10.5194/angeo-37-1223-2019, https://doi.org/10.5194/angeo-37-1223-2019, 2019
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The Earth's radiation belts control the space environment, often affecting the GPS signal propagation and satellite operations. Intense fluxes of energetic particles can penetrate even below the inner belt near the Equator. We analysed electron penetrations under geomagnetic quiet conditions and found in the solar wind an external driver cause. Satellite observations prove that disturbance of the inner belt was associated with impact of plasma jets formed in the solar wind nearby the Earth.
Angélica Sicard, Daniel Boscher, Sébastien Bourdarie, Didier Lazaro, Denis Standarovski, and Robert Ecoffet
Ann. Geophys., 36, 953–967, https://doi.org/10.5194/angeo-36-953-2018, https://doi.org/10.5194/angeo-36-953-2018, 2018
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GREEN (Global Radiation Earth ENvironment) is a new model providing particle fluxes at any location in the radiation belts, for energy between 1 keV
and 10 MeV for electrons and between 1 keV and 800 MeV for protons. This model is composed of global models (AE8 and AP8, and SPM) and
local models (SLOT model, OZONE and IGE-2006 for electrons; OPAL and IGP for protons).
Run Shi, Wen Li, Qianli Ma, Seth G. Claudepierre, Craig A. Kletzing, William S. Kurth, George B. Hospodarsky, Harlan E. Spence, Geoff D. Reeves, Joseph F. Fennell, J. Bernard Blake, Scott A. Thaller, and John R. Wygant
Ann. Geophys., 36, 781–791, https://doi.org/10.5194/angeo-36-781-2018, https://doi.org/10.5194/angeo-36-781-2018, 2018
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Short summary
The nature of the semi-annual variation in the relativistic electron fluxes in the Earth's outer radiation belt has been a debate for over 30 years. Our work shows that it is primarily driven by the Russell–McPherron effect, which indicates that reconnection is responsible not only for the short-scale but also the seasonal variability of the electron belt as well. Moreover, it is more pronounced during the descending phase of the solar cycles and coexists with periods of fast solar wind speed.
The nature of the semi-annual variation in the relativistic electron fluxes in the Earth's outer...