June Lunde

Conditional integration of Incoherent Scattering in relation to flickering aurora

[1] In this report we present incoherent scatter radar (ISR) observations of ionospheric response to precipitation causing flickering aurora. Flickering aurora is caused by electron precipitation with modulations at frequencies higher than 5 Hz. To resolve the variation at these short time-scales with ISR we have integrated together pulses at the same phase of the optical intensity variation observed with high-speed narrow field-of-view imaging in white light to determine the intensity variation in the field aligned direction, which is also the direction of the beam of the EISCAT Svalbard Radar (ESR). Further we show that the 3% modulation in ISR back-scattered power can be explained with electron heating by temporally modulated electron precipitation and electron cooling in collisions with ions and neutrals.