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Common solar wind drivers behind magnetic storm-magnetospheric substorm dependency [article]

Jakob Runge, Georgios Balasis, Ioannis A. Daglis, Constantinos Papadimitriou, Reik V. Donner
2018 arXiv   pre-print
A physical mechanism by which substorms drive storms or vice versa is, therefore, unlikely.  ...  Here, we tackle this issue by applying a causal inference approach to two corresponding indices in conjunction with several relevant solar wind variables.  ...  This work has been financially supported by the joint Greek-German IKYDA 2013 project "Transdisciplinary assessment of dynamical complexity in magnetosphere and climate: A unified description of the nonlinear  ... 
arXiv:1802.02477v1 fatcat:i2xow6qwljgtnoxgyfepsl2nbi

The terrestrial ring current: Origin, formation, and decay

Ioannis A. Daglis, Richard M. Thorne, Wolfgang Baumjohann, Stefano Orsini
1999 Reviews of Geophysics  
During intense magnetic storms, the O ϩ abundance increases dramatically, resulting in a rapid intensification of the ring current and an O ϩ dominance around storm maximum.  ...  The main carriers of the storm ring current are positive ions, with energies from ϳ1 keV to a few hundred keV, which are trapped by the geomagnetic field and undergo an azimuthal drift.  ...  • Daglis et al.: TERRESTRIAL RING CURRENT 37, 4 / REVIEWS OF GEOPHYSICS • Daglis et al.: TERRESTRIAL RING CURRENT 37, 4 / REVIEWS OF GEOPHYSICS , 4 / REVIEWS OF GEOPHYSICS Daglis et al.  ... 
doi:10.1029/1999rg900009 fatcat:6so654luxrg2nnzoqyqpvlpqoy

Evaluation of dynamic scheduling methods in simulations of storm-time ion acceleration

Ioannis Riakiotakis, Georgios Goumas, Nectarios Koziris, Fiori-Anastasia Metallinou, Ioannis A. Daglis
2008 Proceedings, International Parallel and Distributed Processing Symposium (IPDPS)  
In this paper we investigate the applicability of classic dynamic loop scheduling methods on a numerical simulation code that calculates the trajectories of charged particles in the earth's magnetosphere  ...  The growth phase of a substorm can be simulated by the evolution of a given magnetic field level-a, which is represented by a given value of Kp geomagnetic index, to a more disturbed one, levelb (a higher  ...  As a result, the field lines and the plasma drift as a whole, setting on a large-scale circulation inside the magnetosphere, known as convection (see Figure 2 ).  ... 
doi:10.1109/ipdps.2008.4536483 dblp:conf/ipps/RiakiotakisGKMD08 fatcat:44m4krgbivdelamitefwuisvta

Dynamical complexity inDsttime series using non-extensive Tsallis entropy

Georgios Balasis, Ioannis A. Daglis, Constantinos Papadimitriou, Maria Kalimeri, Anastasios Anastasiadis, Konstantinos Eftaxias
2008 Geophysical Research Letters  
The non-extensive Tsallis entropy has been proposed as a measure to investigate the complexity of system dynamics. We employ this method for analyzing D st time series.  ...  aurora displays, and global magnetic disturbances on the Earth's surface [Daglis et al., 2001 [Daglis et al., , 2003 ].  ...  Thus, we stipulate that the symbolic sequence is to be read in terms of distinct successive ''blocks'' of length L, A 1 , A 2 , . . ., A L / A L+1 , . . ., A 2L /A jL+1 , . . ., A (j+1)L . [14] The number  ... 
doi:10.1029/2008gl034743 fatcat:56jat7feijdarfdenniydhbnsy

Common solar wind drivers behind magnetic storm–magnetospheric substorm dependency

Jakob Runge, Georgios Balasis, Ioannis A. Daglis, Constantinos Papadimitriou, Reik V. Donner
2018 Scientific Reports  
Here, we address this issue through a causal inference approach to two corresponding indices in conjunction with several relevant solar wind variables.  ...  Further, our results suggest, at least based on the analyzed indices, that there is no statistical evidence for a direct or indirect dependency between substorms and storms and their statistical association  ...  This work has been financially supported by the joint Greek-German IKYDA 2013 project "Transdisciplinary assessment of dynamical complexity in magnetosphere and climate: A unified description of the nonlinear  ... 
doi:10.1038/s41598-018-35250-5 fatcat:r2clhywbpfggtipn7vgwsvsbai

On the statistics of acceleration and loss of relativistic electrons in the outer radiation belt: a superposed epoch analysis [article]

Christos Katsavrias, Ioannis A. Daglis, Wen Li
2019 arXiv   pre-print
Introduction Earth's outer radiation belt response to geospace disturbances is extremely variable due to the interplay of acceleration and loss mechanisms [Reeves and Daglis, 2016] .  ...  of keV's energy (typically referred as source population) which are injected near midnight from the plasma sheet due to substorm injections [O'Brien et al., 2003b; Baker and Daglis, 2007; Thorne et al  ... 
arXiv:1902.00961v1 fatcat:cqm2htd6i5ffth6s34tvt54dey

An initial ULF wave index derived from 2 years of Swarm observations

Constantinos Papadimitriou, Georgios Balasis, Ioannis A. Daglis, Omiros Giannakis
2018 Annales Geophysicae  
This is the first attempt, to our knowledge, to derive a ULF wave index from LEO satellite data.  ...  utilizing a state-of-the-art high-resolution magnetic field model and Swarm Level 2 products (i.e., field-aligned currents – FACs – and the Ionospheric Bubble Index – IBI).  ...  corresponds to a pulsation with a minimum amplitude of 0.15 nT) are labeled "candidate events".  ... 
doi:10.5194/angeo-36-287-2018 fatcat:c6uxifz6xvewbojnpzs6daf4j4

Investigating dynamical complexity in the magnetosphere using various entropy measures

Georgios Balasis, Ioannis A. Daglis, Constantinos Papadimitriou, Maria Kalimeri, Anastasios Anastasiadis, Konstantinos Eftaxias
2009 Journal of Geophysical Research  
This paper explores the applicability and effectiveness of a variety of computable entropy measures (e.g.  ...  This paper explores the applicability and effectiveness of a variety of computable entropy measures (e.g.  ... 
doi:10.1029/2008ja014035 fatcat:qkcr53ddxzd7xmpzsoxh4v7wx4

A machine learning approach for automated ULF wave recognition

Georgios Balasis, Sigiava Aminalragia-Giamini, Constantinos Papadimitriou, Ioannis A. Daglis, Anastasios Anastasiadis, Roger Haagmans
2019 Journal of Space Weather and Space Climate  
Magnetospheric ultra-low frequency (ULF) waves can have a strong impact on the dynamics of charged particles in the radiation belts, which can affect satellite operation.  ...  Here, we employ a method based on Fuzzy Artificial Neural Networks in order to detect ULF waves in the time series of the magnetic field measurements on board the low-Earth orbit CHAMP satellite.  ...  (Daglis, 2006) .  ... 
doi:10.1051/swsc/2019010 fatcat:wmux75u7wvdjvnkqwq443cv3ly

Highly relativistic electron flux enhancement during the weak geomagnetic storm of April-May 2017 [article]

Christos Katsavrias, Ingmar Sandberg, Wen Li, Olena Podladchikova, Ioannis A. Daglis, Constantinos Papadimitriou, Christos Tsironis, Sigiava Aminalragia-Giamini
2019 arXiv   pre-print
We report observations of energetic electron flux and Phase Space Density (PSD) to show that a relatively weak magnetic storm with Sym-H_min≈ -50 nT, resulted in a relativistic and ultra--relativistic  ...  ., 2013; Reeves and Daglis, 2016] due to the interplay of acceleration and loss mechanisms.  ...  The correlation of geomagnetic activity with the enhancements of MeV electron flux in the outer radiation belt has been recognized for decades [Reeves et al., 2003; Kataoka et al., 2006; Baker and Daglis  ... 
arXiv:1902.00960v1 fatcat:zlkp653bhbbstgxtbcreaq3ala

Quantifying Dynamical Complexity of Magnetic Storms and Solar Flares via Nonextensive Tsallis Entropy

Georgios Balasis, Ioannis A. Daglis, Constantinos Papadimitriou, Anastasios Anastasiadis, Ingmar Sandberg, Konstantinos Eftaxias
2011 Entropy  
The S q for the word length L is S q (L) = k 1 q − 1 ⎛ ⎝ 1 − (A 1 ,A 2 ,...,A L ) [p(L) A 1 ,A 2 ,...  ...  Thus, we stipulate that the symbolic sequence is to be read in terms of distinct successive "blocks" of length L, A 1 , A 2 , . . . , A L /A L+1 , . . . , A 2L /A jL+1 , . . . , A (j+1)L .  ... 
doi:10.3390/e13101865 fatcat:s2bqu65pmfcn5epykq56uoh3ae

The virtual enhancements − solar proton event radiation (VESPER) model

Sigiava Aminalragia-Giamini, Ingmar Sandberg, Constantinos Papadimitriou, Ioannis A. Daglis, Piers Jiggens
2018 Journal of Space Weather and Space Climate  
A new probabilistic model introducing a novel paradigm for the modelling of the solar proton environment at 1 AU is presented.  ...  The virtual enhancements À solar proton event radiation model (VESPER) uses the European space agency's solar energetic particle environment modelling (SEPEM) Reference Dataset and produces virtual time-series  ...  a 1 year or a 7 year period.  ... 
doi:10.1051/swsc/2017040 fatcat:o52il2sovndyxgscqc7dqn3zha

Detection of Dynamical Complexity Changes in Dst Time Series Using Entropy Concepts and Rescaled Range Analysis [chapter]

Georgios Balasis, Ioannis A. Daglis, Anastasios Anastasiadis, Konstantinos Eftaxias
2011 The Dynamic Magnetosphere  
We show the emergence of two distinct patterns in the geomagnetic variability of the terrestrial magnetosphere: (1) a pattern associated with intense magnetic storms, which is characterized by a higher  ...  degree of organization (i.e., lower complexity or higher predictability for the system) and persistent behavior, and (2) a pattern associated with normal periods, which is characterized by a lower degree  ...  As an extension of this application, we will consider in the near future a basic space weather challenge (Daglis et al. 2001 (Daglis et al. , 2003 , i.e., the problem of continuous monitoring of the magnetospheric  ... 
doi:10.1007/978-94-007-0501-2_12 fatcat:nizmeq7ilrek5nly7mszhvx3em

Universality in solar flare, magnetic storm and earthquake dynamics using Tsallis statistical mechanics

Georgios Balasis, Ioannis A. Daglis, Anastasios Anastasiadis, Constantinos Papadimitriou, Mioara Mandea, Konstantinos Eftaxias
2011 Physica A: Statistical Mechanics and its Applications  
The observed similarity suggests a common approach to the interpretation of these diverse phenomena in terms of driving physical mechanisms that have the same character.  ...  We show that X-ray flux and D st time series during powerful solar flares and intense magnetic storms, respectively, obey a nonextensive energy distribution function for earthquake dynamics with similar  ...  The entropic index q characterizes the degree of nonextensivity reflected in the following pseudo-additivity rule S q (A + B) = S q (A) + S q (B) + 1−q k S q (A)S q (B).  ... 
doi:10.1016/j.physa.2010.09.029 fatcat:omw2dvqyt5bhre4uvaq4edi2hi

On the semi-annual variation of relativistic electrons in the outer radiation belt

Christos Katsavrias, Constantinos Papadimitriou, Sigiava Aminalragia-Giamini, Ioannis A. Daglis, Ingmar Sandberg, Piers Jiggens
2021 Annales Geophysicae  
We perform wavelet and cross-wavelet analysis in a broad energy and spatial range of electron fluxes and examine their phase relationship with the axial, equinoctial and Russell–McPherron mechanisms.  ...  Furthermore, the analysis of the past three solar cycles with GOES/EPS indicates that the semi-annual variation at geosynchronous orbit is evident during the descending phases and coincides with periods of a  ...  not affected at all due to the interplay of acceleration and loss mechanisms (Reeves et al., 2003; Katsavrias et al., 2015; Turner et al., 2015; Reeves and Daglis, 2016; Katsavrias et al., 2019a; Daglis  ... 
doi:10.5194/angeo-39-413-2021 fatcat:n3nkc7przrecfph6p7z6evnlyi
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