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Item Lithosphere atmosphere ionosphere coupling during the September 2015 Coquimbo earthquake(Springer Nature Link) Adhikari, Bhoj Raj; Klausner, Virgínia; Cândido, Claudia Maria Nicoli; Poudel, Prakash; Macedo, Humberto Gimenes; Silwal, Ashok; Gautam, Sujan Prasad; Calabia, Andrés; Shah, MunawarThis study explores temporal variations in seismic data, interplanetary parameters, and geomagnetic indices during the 2015 Coquimbo earthquake. We employ wavelet transform techniques to investigate potential coupling mechanisms between the lithosphere, atmosphere, and ionosphere (LAI), even during geomagnetically disturbed periods. Our analysis is strengthened by evaluating geomagnetic data and all- sky images within a 2000–3000 km radius of the epicenter. We explore the post-Chilean earthquake seismogenic perturbations in the upper atmosphere on September 16–17, 2015. Coseismic and post- seismic events emerge in the Brazilian region 1–3 hrs after the earthquake onset. The co-occurrence and subsequent response of these disturbances to seismic events suggest their seismogenic nature. Addi- tionally, we utilize geomagnetic storm and interplanetary magnetic Beld (IMF) indices to differentiate magnetic Cuctuations arising from solar storms during seismic events. While our study detects magnetic disturbances associated with seismic activity, distinguishing them from the eAects of solar storms in the geomagnetic records or all-sky images remains challenging. These observations prompt further investigation into the intricate interplay between geomagnetic and ionospheric disturbances and their connection to seismic and geomagnetic storm activity.Item Enhancing learning of the Grad-Shafranov Equation through scientific literature: part 1 of a physics education series(Sociedade Brasileira de Física) Ojeda González, Arian; Santos, Lenadro Nunes dos; La Luz, Victor Hugo de; Oliveira, Matheus Felipe Cristaldo de; Sousa, Antonio Nilson Laurindo; Prestes, Alan; Klausner, Virgínia; Pilling, SergioThis article provides a comprehensive review of relevant studies in the fields of plasma physics, electromagnetism, and space physics. The aim is to demonstrate how the study of the scientific literature can be used to enhance problem-solving abilities and develop innovative solutions in physics. In this paper, we focus on the study of solutions of the specific Grad-Shafranov equation. Two of the new solutions proposed by Yoon and Lui (2005) are used as a basis for the development of a new solution. The new solution presented has singular points similar to the Yoon-Lui-2 solution, but with an inverted configuration, and also presents less rounded double islands compared to the Yoon-Lui-2 solution. Additionally, the new solution does not exhibit the formation of a current ring, a characteristic of the Yoon-Lui-1 solution, and varying its parameters may lead to higher plasma confinement efficiency. In summary, we illustrate how a thorough analysis of literature can serve as a powerful means for generating innovative approaches to resolving theoretical issues in physics.Item Assessing the effects of a minor CIR‐HSS geomagnetic storm on the brazilian low‐latitude ionosphere: ground and space‐based observations(Advancing Earth and Space Sciences) Chingarandi, Frank Simbarashe; Cândido, Claudia Maria Nicoli; Guedes, Fabio Becker; Jonah, Olusegun Folarin; Santos, Stella Pires Moraes; Klausner, Virgínia; Osanyin, Taiwo OlusayoThis paper investigates the effects of a minor G1 Co-rotating Interaction Region (CIR)/High-Speed Stream (HSS)-driven geomagnetic storm that occurred on (13–14 October 2018), during deep solar minimum. We used simultaneous observations from multiple instruments, namely; ground-based Global Navigation Satellite Systems (GNSS) receivers, a Digisonde, ground magnetometers, and space-based observations from the National Aeronautics and Space Administration Global-scale Observations of Limb and Disk (GOLD) and SWARM missions. This study presents a detailed picture of the low-latitude ionosphere response over the Brazilian sector during a minor storm. Our results showed that the minor CIR/HSS-driven storm caused a positive ionospheric storm of over ∼20 TECU in magnitude. For the first time, periodic post-sunset irregularities and Equatorial Plasma Bubbles, equatorial plasma bubbles, were analyzed using GOLD FUV OI 135.6 nm emission, Total Electron Content (TEC) maps, Rate of TEC index, ROTI, and TEC gradients. Fluctuations in the interplanetary magnetic field Bz and changes in the thermospheric column density ratio (∑O/N2) are discussed as the main sources of ionospheric changes during the storm. This paper highlights the importance of monitoring and understanding the impact of Sun-Earth interactions and provides insight into the behavior of the low-latitude ionosphere during minor geomagnetic storms.