%0 Conference Proceedings
%T Geomagnetic Storm Effects on The Signatures of Equatorial Electrojet Plasma Irregularities
%A Aveiro, Henrique Carlotto,
%A Denardin, Clezio Marcos,
%A Abdu, Mangalathayil Ali,
%A Schuch, Nelson Jorge,
%@affiliation Instituto Nacional de Pesquisas Espaciais, Rio Grande do Sul,
%@affiliation Instituto Nacional de Pesquisas Espaciais, Divisão de Aeronomia(INPE, DAE),
%B El Leoncito School on Solar Physics, 3.
%C San Juan
%8 28 de novembro a 5 de dezembro
%X A 50 MHz coherent back-scatter radar, also known by the anachronism RESCO, has been operated in Brazil since 1998 at São Luís (2.33° S, 44.2 °W, DIP: -0.5), on the dip equator to study the equatorial electrojet dynamics. Spectral analyses of the received echoes from equatorial electrojet (EEJ) irregularities allow us to identify the dominant type of plasma instabilities in the electrojet bulk. From the frequency distribution of the irregularities echoes power spectra; we are also able to deduce the Doppler shift caus ed by the irregularities drift in relation to the radar beam. Such drift is close related to the electric fields that drives the plasma instabilities. Through the analysis of the spectrograms (each one corresponding to one range gate) in disturbed periods, it has been possible to observe effects in the EEJ electric fields associated with possible prompt penetration (PP) electric fields. The PP electric fields show themselves as increases or decreases in the generation of 3-meter plasma irregularities, according to its polarity in relati on to the EEJ electric fields. This paper shows the RESCO spectrograms with increases/decreases of 3-meter EEJ irregularities generation associated with possible PP electric fields in geomagnetic disturbed days as well as the results of EEJ in quiet days. The methodology and the results are discussed and analyzed.