OI 630.0‐nm and N₂ 1PG emissions in pulsating aurora events observed by an optical spectrograph at Tromsø, Norway

We performed observations of pulsating aurora (PsA) with an optical spectrograph at Tromsø, Norway, during wintertime in 2016–2017. The data analysis of multiple PsA events revealed the PsA spectra for the first time. As the results, the OI 630.0‐nm emissions and the N₂ 1PG emissions were found in the both spectra during brighter (ON) and darker (OFF) phases in the PsA events. The spectra of pulsations were derived as difference spectra between the ON and OFF spectra. From the obtained spectra of pulsations, it is found that dominant pulsations at 630.0 nm were coming from the N₂ 1PG (10,7) band, and there were less or minor contributions of the OI 630.0 nm to pulsations at 630.0 nm.