Recent  

To construct realistic models of the RC that describes its structure during magnetic storms of different intensity, quantitative patterns of the variations of the main parameters of the radial profile of the RC energy density are necessary. Such patterns are of high importance both for theoretical studies and mathematical modeling of the dynamics of the magnetosphere, and for many applied problems.

In this work, we analysed and compared measurements of electrons 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 altitude, the correlation between the instruments was found to be good.

Substorms are a phenomenon in the magnetosphere-ionosphere system, which is characterised by brightening of an auroral arc and enhancement of electric currents in the polar ionosphere. Since substorms are difficult to predict, this study treats a substorm occurrence as a stochastic phenomenon and represent the substorm occurrence rate with a machine learning model. We then analyse the response of substorm activity to solar wind conditions by feeding synthetic solar wind data into the model.

We have improved a new method for modeling the interaction between the solar wind and Mars, which uses a hybrid model to fit the observed bow shock location to determine a corresponding exobase ion upflux. The method was applied to one MAVEN orbit to investigate the effects on ion escape estimates of assumed heavy ion composition in the ionosphere, alpha particles in the solar wind, solar wind velocity aberration and electron temperature. We also studied the morphology of the escaping ions.

A new method is proposed for determining the precursors of upcoming earthquakes, which is based on the change in the level of small-scale fluctuations of the empirical probability density of the measured physical field under the influence of the process of "final preparation" of a seismic event. This makes it possible to study seismic processes with a fairly accurate reference to the current time.

The present study discusses the modeling and interpretation of magnetospheric structures via electromagnetic knots for the first time. The mathematical foundations of electromagnetic knots are presented and the formalism is reformulated in terms of the classical wave telescope technique. The method is tested against synthetically generated magnetic field data describing a plasmoid as a two-dimensional magnetic ring structure.

We derive, for whistler mode chorus waves and relativistic electrons, the wave-particle interaction time (IT) equation considering the effects of the special relativity theory. Results show that IT has a non-linear dependence on the wave group velocity, electrons' energy, and initial pitch angle. The IT can be ~ 50 % lower for disturbed periods. The change in pitch angle is also underestimated. Our results provide subsidies to improve the outer radiation belt electron flux variation modeling.

The upper detection limit in reciprocal space, the spatial Nyquist limit, is derived for arbitrary spatial dimensions for the wave telescope analysis technique. This is important as future space plasma missions will incorporate larger numbers of spacecraft (>4). Our findings are a key element in planning the spatial distribution of future multi-point spacecraft missions. The wave telescope is a multi-dimensional Fourier transform estimator; hence, this can be applied to other fields of research.

The solar wind is in the state of plasma, and can exhibit a range of phenomena like waves and instabilities. One observed phenomenon in the solar wind is magnetic holes (MH). They are localized depressions of the magnetic field. We have studied the motion of MHs, by using the multispacecraft ESA Cluster mission. We derive their velocities in the solar wind frame, and find that both linear and rotational MH are convected with the solar wind.

H₂O-Lyman alpha response is modified by NLC formation resulting in positive response at the ice formation region (due to temperature change effect on the ice formation rate) and negative response at sublimation zone (due to photolysis effect).

The in-depth study of the ionospheric electron density profile contributes significantly to our understanding of the ionosphere, its dynamic nature and characteristics of radio wave for telecommunication. it was observed that the results from Ilorin and Fortaleza are similar and that of Jicamarca are different from those of other two stations. This is the second time in our studies that two stations from different latitude will be presented as being having similar profile.

This article reports on an observational overview of 31 Type II bursts observed in cycle 25 from May 2021 to December 2022. The space weather implications in terms of ionospheric total electron content (TEC) enhancement is also evaluated. The findings from this study provide the possibility of tracking the progress of the current solar activity.