@InProceedings{SilviaSVARASDMCMAWALL:2024:WhCaAu,
               author = "Silvia, Ligia Alves da and Shi, Jiankui and Vieira, Luis Eduardo 
                         Antunes and Agapitov, Oleksiy and Resende, Laysa Cristina 
                         Ara{\'u}jo and Alves, Livia Ribeiro and Sibeck, David G. and 
                         Deggeroni, Vinicius and Marchezi, Jos{\'e} Paulo and Chen, Sony 
                         Su and Moro, Juliano and Aras, Christina and Wang, Chi and 
                         Andrioli, V{\^a}nia F{\'a}tima and Liu, Zhengkuan and Li, Hui",
          affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and 
                         {China-Brazil Joint Laboratory for Space Weather} and {Instituto 
                         Nacional de Pesquisas Espaciais (INPE)} and {China-Brazil Joint 
                         Laboratory for Space Weather} and {Instituto Nacional de Pesquisas 
                         Espaciais (INPE)} and {Instituto Nacional de Pesquisas Espaciais 
                         (INPE)} and {China-Brazil Joint Laboratory for Space Weather} and 
                         {Instituto Nacional de Pesquisas Espaciais (INPE)} and {Instituto 
                         Nacional de Pesquisas Espaciais (INPE)} and {Instituto Nacional de 
                         Pesquisas Espaciais (INPE)} and {Instituto Nacional de Pesquisas 
                         Espaciais (INPE)} and {China-Brazil Joint Laboratory for Space 
                         Weather} and {China-Brazil Joint Laboratory for Space Weather} and 
                         {Instituto Nacional de Pesquisas Espaciais (INPE)} and 
                         {China-Brazil Joint Laboratory for Space Weather} and 
                         {China-Brazil Joint Laboratory for Space Weather}",
                title = "Why Can the Auroral-Type Sporadic E Layer Be Detected Over the 
                         South American Magnetic Anomaly (SAMA) Region? An Investigation of 
                         a Case Study Under the Influence of the HighSpeed Solar Wind 
                         Stream",
            booktitle = "Proceedings...",
                 year = "2024",
         organization = "Conferencia Latinoamericana de Geof{\'{\i}}sica Espacial, 14.",
             abstract = "We present a study of the large amplitude longitudinal 
                         oscillations observed in two solar filaments (F1 and F2), prior to 
                         their eruptions. To analyze a possible implication of oscillations 
                         in the precursor processes of eruptive events, we analyzed the F1 
                         and F2 oscillation periods and their variations during the pre- 
                         and post-eruption of filaments, the formation of coronal mass 
                         ejection (CME) and the corresponding magnetic field evolution. The 
                         F2 pre-eruption oscillations, exhibit a period of approximately 1 
                         hour, aligning with previous reports. Applying a mathematical 
                         model and assuming a plasma density of 1.6 x 1011 cm-3 (Luna, M., 
                         \& Karpen, J. 2012), we estimate the minimum magnetic field 
                         values of 95G for F1 and 33G for F2. Our results show that the F2s 
                         magnetic field is similar to previously reported values, while the 
                         F1s magnetic field is unexpectedly high and challenges previous 
                         estimations of the filaments magnetic field. In addition, we 
                         establish a connection between the onset of observed longitudinal 
                         oscillations and the appearance of new photospheric magnetic 
                         fluxes, triggering a magnetic reconnection process. The F2 
                         pre-eruption oscillations are related to the F2 eruption and 
                         formation of the associated CME, while we note the absence of any 
                         CME immediately after the F1 eruption; although, F1 also undergoes 
                         pre-eruption oscillations, it is accompanied by a gradual and slow 
                         expansion of F1, unlike the F2, leading to the F1 eruption and 
                         formation of partial halo CME only four days after the onset of F1 
                         expansion. A more detailed analysis, using wavelet techniques 
                         reveals the temporal variations of oscillation periods, suggesting 
                         a link with the filaments body expansion process and variation of 
                         filaments geometric properties, particularly their curvature 
                         radius. In summary, the proposed model indicates that the filament 
                         oscillation periods and their variations are highly correlated 
                         with the evolution of the filament geometric properties, the 
                         linked magnetic configuration, their eruption and formation of 
                         CMEs. More comprehensive studies are needed to verify our 
                         results.",
  conference-location = "Monterrey, Mexico",
      conference-year = "08-12 Apr. 2024",
             language = "en",
        urlaccessdate = "06 maio 2024"
}