Institut national de recherche scientifique français Univerité Pierre et Marie Curie Université Paris Diderot - Paris 7

Studies of terrestrial Auroral Kilometric Radiation with the Wind spacecraft

mercredi 26 mai 2021, par James Waters (University of Southampton)

Vendredi 28 mai 2021 à 11h00 , Lieu : En visioconfĂ©rence

Auroral Kilometric Radiation (AKR) is terrestrial radio emission that is generated via the electron-cyclotron maser instability and has long been observed to be associated with energy deposition and interactions between the magnetosphere and ionosphere. Emitted from both hemispheres, an increase in the amplitude of a particular AKR source is indicative of the presence of strong, parallel electric fields in the auroral zone, while the emission frequency of AKR gives direct insight into the altitudinal extent of the source region. The viewing geometry is complex, however, due to the primary confinement of the source regions to local times on the nightside and the anisotropy of the beaming pattern seen at each pole. A new empirical technique has been developed that allows AKR emission to be isolated from remote sensing observations made by the Wind spacecraft. The method is applied to a month-long period in 1999 over which Wind completed close to two, precessing petal orbits while the Cassini spacecraft performed a close flyby of Earth and also recorded AKR. My talk will discuss the details of the selection and present the results of its application to these observations, which reproduces the AKR viewing geometry as well as previously observed diurnal modulations. Current and future uses of the resulting dataset will also be explored.