Cancelled: Electron density estimation from 150 km echoes using the JULIA database: Comparing to IRI and Digisonde data

Equatorial ionospheric radars can observe strong coherent echoes at around 150 km altitude with a finite number of layers and gaps vertically organized. Even though the physical mechanism that produces them is still not fully understood, mounting evidence suggests that the gaps occur at heights where the local upper hybrid frequency is a multiple of the gyrofrequency. However, there is not yet a method to determine this multiplicity factor.

In this work, we developed a technique to identify the gaps on the 150 km echoes and applied it to the 20 years of SNR data collected with the Jicamarca radar operating in JULIA (Jicamarca Unattended Long-term Investigations of the Ionosphere and Atmosphere) mode. The analysis was applied to signal-to-noise ratio maps and resolved one gap in its structure. Then, electron densities were estimated using the expressions for the upper hybrid frequency and estimates from IGRF for the local geomagnetic field. These electron density estimates were compared to IRI and SAMI2 models, and the Jicamarca Digisonde data. Our results suggest that JULIA has promising capabilities to produce electron density estimates in the valley region.