Solar flare effect on the geomagnetic field and ionosphere

• Autores: Meza, Amalia Margarita; Van Zele, Maria Andrea; Rovira, Marta Graciela
• Año de publicación: 2009
• Idioma: inglés
• Tipo de recurso: artículo
• Materia: Flare; Vtec; Geomagnetic Field
• Institución: Consejo Nacional de Investigaciones Científicas y Técnicas

This paper studies the ionospheric and geomagnetic response to an X6.2 solar flare recorded at 14:30 UT on December 13, 2001, in quiet geomagnetic conditions which allow the variations in the geomagnetic field and ionosphere measurements to be easily related to the solar flare radiation. By using measurements from the global positioning system (GPS) and geomagnetic observatories, the temporal evolution of ionospheric total electron content variation, vTECV, and geomagnetic field variations, [delta]B, as well as their rates of variation, were obtained around the subsolar point at different solar zenith angles. The enhancement of both parameters was recorded one to three minutes later than the Geostationary Operational Environmental Satellite (GOES) programme recording; such delay tends to depend on the latitude, longitude, and solar zenith angle of the observatory's observations. The vTECV is related to the local time and the [delta]B to the intensity and position of the ionospheric currents. The vTECV's maximum value is always recorded later than the maximum values reached by [delta]B and the X-ray intensity. The maximum [delta]B is larger in the local morning than in the afternoon. The rates of vTECV and [delta]B have two maximum values at the same time as the maximum values recorded by H[alpha] (for each ribbon). This work shows the quantitative and qualitative relations between a solar flare and the ionospheric and geomagnetic variations that it produces.
Fil: Meza, Amalia Margarita. Universidad Nacional de la Plata. Facultad de Ciencias Astronómicas y Geofísicas; Argentina
Fil: Van Zele, Maria Andrea. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina
Fil: Rovira, Marta Graciela. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; Argentina