Two-dimensional high-resolution imaging of the equatorial plasma fountain

Abstract

The first visual representation of the reverse equatorial plasma fountain during night-time has been made using images obtained by an All Sky Imaging Fabry-Perot Spectrometer observing the OI 630.0 nm airglow emission line from the thermosphere; the intensity of this line emission is directly related to the F-region plasma densities during night-time. From the identifiable features when the enhanced airglow emitting region moves overhead and when it completely leaves the field-of-view, the equatorwards velocity of the EIA has been estimated to be ∼150 km/h at the latitude of the measurements (Mt Abu, 20° 20' dip latitude, India). Lower limits for the latitudinal and longitudinal extents of the EIA crest have each been inferred to be 6°.