Spatial pattern of events with simultaneous recording of riometric absorption and auroral VLF hiss

We have assessed the position and size of the region of increased absorption in the ionosphere for events of simultaneous recording of auroral hiss and bursts of cosmic radio noise absorption, using observational data from the Lovozero and Tumanny observatories. To estimate the size and position of this region, a numerical model, we have developed based on the Monte Carlo method, was employed. Simulation of events with an absorption level >0.4 dB and significant spatial variation between observation points has shown that the region of increased absorption is limited in latitude and shifted northward relative to the illumination region of the auroral hiss. The results obtained make it possible to quantitatively explain the simultaneous recording of cosmic radio noise absorption bursts and auroral hiss near the Earth surface. In some cases, the position of the reconstructed absorption region matches the position of the auroral arc observed in the optical range. The results confirm the effectiveness of the developed model for diagnosing the spatial distribution of the region of increased absorption in the ionosphere from ground-based measurements.