## 3 Data and Methods
### Ionospheric Data
These measurements provide invaluable insights into various phenomena, including radiation belt populations, energetic solar proton events, and the low-energy segment of the galactic cosmic-ray population. Specifically tailored for electron detection, the two telescopes within MEPED delineate three energy bands ranging from 30 keV to 2.5 MeV. The first telescope, angled at 9\({}^{\circ}\) towards the local zenith, captures one perspective, while the second telescope, positioned orthogonally at 90\({}^{\circ}\) along the satellite's motion, provides a complementary view. Each compact solid-state detector boasts nominal geometric acceptances of 0.1 cm\({}^{2}\)sr and opening angle apertures of \(\pm\)15\({}^{\circ}\). Statistical correlations between strong EQs and electron bursts (EBs) detected by NOAA were mainly observed considering seismic events around the equator in both the West and East Pacific [62; 63]. It was in agreement with the bouncing points of the inner Van Allen Belt (VAB), points where electrons go down close to the earth's surface, which are also around the equator and cross the ring of fire twice. However, the inner VAB does not generally overhang latitudes above 35\({}^{\circ}\), while mid-latitude EQs are located below the slot region between the internal and external VABs. Seismic events occurring at mid latitudes have therefore apparently minor probability to interact with trapped particles. The representation of a possible interaction scenario between mid-latitude seismic events and trapped electrons is depicted in Figure 6, where the possible area to observe EBs connected to the Fano EQ is shown in pink color. These areas have a longitude range of a few tenths of degrees around those of the seismic event. In fact, the longitude of the seismic event is close to the South Atlantic Anomaly (SAA) border longitude, and the electrons' mirror points that are far from the SAA longitude will hardly descend to the satellite altitude. Thus, the probability of bouncing electrons to cross the satellite decreases getting away from the SAA. For what concerns the lower latitude EBs, electrons are thought to be coming (direction indicated with pink arrow) from the inner VAB (in yellow), with the interaction (in blue) running along the magnetic field lines. Instead, for what concerns mid-high latitude EBs, electrons are thought to be escaping the trapped conditions (direction indicated with another pink arrow) from the external VAB (still in yellow), with the interaction (still in blue) connecting the two phenomena along the minimum path. The geomagnetic lines (in green) of the internal VAB can cross the lithosphere up to 30\({}^{\circ}\)-35\({}^{\circ}\) in latitude, so being unlikely to be affected by tectonic activity, whereas the radial propagation of LAIC (in blue) should be able to intercept with greater probability the external belts. Given the pivotal role of geomagnetic activity in perturbing the ionosphere, instances where the ap and Dst indices exceeded some predefined thresholds were excluded from the ionospheric data analysis. We also verified that no X-class flares occurred during the detected ionospheric anomalies.