Morphology of Auroral Events from Simultaneous Atomic and Molecular Emission Observations with HiT&MIS

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.