Estimated nitric oxide density in auroras from ground-based photometric data

In this paper, we numerically estimate the nitric oxide density in auroras, using photometric data on 427.8, 557.7, and 630.0 nm emission intensities. The data were obtained at midnight at observatories of the Polar Geophysical Institute. These estimates were made using a numerical modeling procedure with a time-dependent model of the auroral ionosphere [Dashkevich et al., 2017]. It is shown that the NO density in the maximum of the altitude profile is between (1÷3.3)∙10^8 cm–3. The obtained estimates indicate the absence of a correlation between the [NO]max values and 427.8 nm emission intensities.