Deriving Physical Parameters of Auroral Event from Simultaneous Atomic and Molecular Emissions

This study utilizes the simultaneous spectral observations of the OI 630.0 nm (Red Line), OI 557.7 nm (Green Line), and molecular band emissions in the 780-790 nm range obtained with the High Throughput & Multislit Imaging spectrograph (HiT&MIS). HiT&MIS is deployed in Kiruna, Sweden (67.8° N, 20.2° E) and has been collecting continuous data since January 2025. The instrument features a long slit covering a 40° × 0.1° field of view and a spectral resolving power (λ/∆λ) of ~ 15,000.
We investigate the morphology of the Red Line, Green Line, and molecular band emissions over several auroral events. The molecular emissions are not present in all cases and exhibit event-to-event variability in both intensity and position along the slit. These observations provide an empirical characterization of the relationship between atomic and molecular auroral emissions.