Fig. 3From: Characteristics and longitudinal extent of VLF quasi-periodic emissions using multi-point ground-based observations10-min plot wave spectra on 31 January 2018. Wave spectra at a KAN and b IST detected on 31 January 2018 from 02:30 to 02:40 UT showing two QP emissions with different properties at the two locations. This event corresponds to the ‘simultaneous QP’ groupBack to article page