Fig. 2From: Occurrence characteristics of electromagnetic ion cyclotron waves at sub-auroral Antarctic station Maitri during solar cycle 24a The spectrogram of the total magnetic field variation, and b corresponding plot of averaged powers for different frequency bins are depicted as a function of universal time (UTÂ =Â LT-0.77 h) for EMIC wave activity observed on 6 September 2017. The intervals of EMIC wave activity are mentioned in the lower panel and they are marked with black, red and blue dotted vertical lines for \(f_1\), \(f_2\) and \(f_3\) frequency bins, respectively. The \(\delta _{1-6}\) represent the durations of EMIC waves in these three frequency bins. The total EMIC duration for this day is 3.58 h. The white boxes marked by letters A, B and C represent EMIC wave events with very low powerBack to article page