Frequency and Spectral Analysis of Pulsating Auroras According to Data from an Imaging Photometer at the Verkhnetulomsky Observatory

Abstract

A system of imaging photometers with high temporal resolution (PAIPS, the Pulsating Aurora Imaging Photometers System) is being created at the observatories of the Polar Geophysical Institute on the Kola Peninsula in order to study the structure of pulsating auroras (PsA) in the near ultraviolet range (300–400 nm). Two PsA measurements using the PAIPS system in combination with all-sky cameras are described. A frequency analysis of the signal is performed for the first one. It is shown that pulsations occur within 1.5 h at a quasi-constant frequency of around 1 Hz. The ratio of intensities in lines 337 and 391 nm is measured for the second one. An analysis of simultaneous observations by the optical cameras in the spectrometer’s field of view shows that pulsations of radiation in the on phase are “greener” (i.e., they correspond to less energetic precipitating electrons). Stereometric observations using the camera at the Lovozero observatory yield the maxima of the coefficient of correlation for the time series of the cameras at altitudes of 145–150 and ~92 km.