| Full text | |
| Author(s): |
Mendes, Odim
;
Adhikari, Binod
;
Domingues, Margarete Oliveira
;
Echer, Ezequiel
;
Takeshi, Rodrigo Seo
Total Authors: 5
|
| Document type: | Journal article |
| Source: | Brazilian Journal of Physics; v. 52, n. 5, p. 20-pg., 2022-10-01. |
| Abstract | |
As known, geomagnetic storms and substorms are caused by intensified solar wind-magnetosphere energy coupling processes. Recorded on the ground at high latitudes as geomagnetic disturbances, High-Intensity Long-Duration Continuous Auroral Electroject Activities (HILDCAAs) occur related to the same magnetospheric processes. Improving the magnetic effect understanding during HILDCAAs, this work investigates the characteristics of similar geomagnetic effects at the high and low latitudes from those kinds of events. A strategy is to deal with case studies; we selected HILDCAAs involving different interplanetary scenarios. One primary situation is HILDCAA not preceded by a geomagnetic storm; another situation is HILDCAA preceded by a Corotating Interacting Region (CIR) storm. Finally, there is HILDCAA preceded by an Interplanetary Coronal Mass Ejection (ICME) storm. A geomagnetically quiet case has also been examined as part of the cases to a complete comparison. The methodology involves three numerical approaches. A signal-normalised equivalent-energy variable for the auroral index AE and low-latitude asymmetric ring current geomagnetic index asy-H aid in highlighting similarities in the signal regimes. Together a dynamical time distortion analysis identifies the lags between the magnetic effect regimes. Wavelet multiscale analyses allow spectral characterisation in those effects during the coupling processes. Undoubtedly, the general criteria currently maintain applicable to categorise the HILDCAA events. Nevertheless, using well-defined quantitative approaches, the results point out non-linear peculiarities superposed on the general expected pattern. At the same time, the results show that phenomena recognised under a unique designation present rich details, differing among them by the influence of a complicated coupling process linked to the alternate triggerings of the frontal magnetic reconnection and the viscous interaction on the magnetopause flanks. (AU) | |
| FAPESP's process: | 15/25624-2 - Development of multiscale modelling for non-linear local plasma instabilities of Astrophysics and Space Geophysics |
| Grantee: | Margarete Oliveira Domingues |
| Support Opportunities: | Regular Research Grants |
| FAPESP's process: | 20/13015-0 - Annual Plan for Application of the Technical Reserve Installment for Institutional Infrastructure Costs for Research: Update and optimization of antenna testing facilities, repair of multi-user equipment and acquisition of new equipment |
| Grantee: | Carlos Alexandre Wuensche de Souza |
| Support Opportunities: | Research Grants - Technical Reserve for Institutional Research Infrastructure |
| FAPESP's process: | 18/21657-1 - Study of Jupiter magnetospheric auroral radio activity variability |
| Grantee: | Ezequiel Echer |
| Support Opportunities: | Regular Research Grants |