Physics logo
Lancaster University Homepage
You are here:  SPP / Projects / Future Projects / Hall Pedersen Conductance
DASI optical observations at 557.7 nm have been successfully used to produce all-sky maps of Pedersen conductance. The method was calibrated using EISCAT data at one point and then applied to the entire DASI field of view of 520x520 km. The technique worked well because Pedersen conductance and the 557.7 nm optical emission both maximise in the E-region. However, the electrojet, which constitutes a major portion of the total ionospheric current, is a Hall current occurring at lower altitudes. The strength and direction of currents is determined by the temporal and spatial morphology of the conductance distribution. Since the Hall conductance maximises at lower altitudes than Pedersen conductance, it is much more dependent on the energy of the precipitating particles. Hence it is essential that multi- wavelength observations (e.g., 427.8 and 557.7 nm) be used to determine the energy- dependent component of the particle precipitation producing the Hall conductance. All-sky maps of Hall conductance, in additional to Pedersen conductance, are important since they will facilitate the study of ionospheric currents, which constitute an integral part of the magnetic field-aligned currents coupling the ionosphere to the magnetosphere.
A Lancaster University approved page by webmaster.
© Lancaster University.