The influence of the 15^th January 2010 annular solar eclipse on traveling ionospheric disturbances (TIDs) and equatorial plasma bubbles (EPBs) is studied using data from six global navigation and satellite system (GNSS) receivers spread across the path of annularity over the low latitude region of East Africa. The GNSS receivers are stationed at Nairobi (RCMN), Malindi (MAL2), and Eldoret (MOIU) in Kenya; Mbarara (MBAR) in Uganda; Kigali (NURK) in Rwanda; and Mtwara (MTWA) in Tanzania. The study period ranges from 12^th to 18^th January 2010, three days before and after the 15^th January 2010 annular solar eclipse. The year 2010 marked the beginning phase of solar cycle 24, evidently observed in low total electron content (TEC) values and the disturbed storm time index (Dst). The eclipse started at 7:06 LT and ended at 10:14 LT, with MOIU and RCMN experiencing eclipse magnitudes of 0.946 and 0.93, respectively. The maximum obscuration occurred between 8:21 LT and 8:34 LT across most of the stations. A detrending on vertical TEC (VTEC) derived from GNSS receivers across or close to the path of totality revealed a reduction of 2-3 TECU during the maximum phase of the eclipse. The level of reduction was highly close to the totality path and decreased smoothly away from the totality path. Using a background polynomial fitting technique on diurnal TEC, we analyzed TIDs along NURK-MBAR-MOIU and MOIU-RCMN-MAL2 GPS arrays. The results revealed a wavelike perturbation with a virtual horizontal velocity of 830m/s and 1 TECU amplitude propagating eastward along the MOIU-RCMN-MAL2 GPS array. The study reports a moderate scintillation activity of 0.5ROTI0.9 values, demonstrating the presence of few EPBs over the region. The results show a latitudinal variation in GPS-TEC scintillation activities and suggest a possible influence of the eclipse on the observed increase in average scintillation levels across East Africa.

During sand and dust storm (SDS) events, atmospheric suspension and transport of sand and dust brings a reasonable amount of electrification in the atmosphere which plays a very important role in the atmosphere-ionosphere coupling. The Godzilla SDS began on 5^th June 2020 in Algeria following a decrease in pressure and spread to other areas across the Sahara between 6^th and 28^th June 2020. Using SDS data from Copernicus Sentinel-5P satellite mission and Vertical Total Electron Content (VTEC) data from four GNSS receiver stations: IFR1 (Ifrane Seismic), MELI (Melilla), TETN (Tetouan) and OUCA (Ouca) over Morocco, we investigate the possible ionospheric TEC variability over the four GNSS receiver stations during the Godzilla SDS event which was tracked using the Sentinel-5P Satellite mission. Solar wind parameters: Horizontal component of Interplanetary Magnetic Field (IMF-Bz), interplanetary Electric Field (IEF-Ey) and solar wind speed (V) and geomagnetic indices: Disturbance Storm Time (Dst) and Planetary K (Kp) indices were examined and showed very minimal geomagnetic influence during the period. We observed major ionospheric disturbances over the four Global Navigation Satellite System (GNSS) receiver stations on 16^th, 17^th, 18^th, 21^st, 22^nd, 23^rd 25^th and 26^th June 2020: the period with the Sentinel-5P Aerosol Index (SAI) of more than 4 as recorded by the Sentinel-5P Satellite engine. The daily VTEC values over the four GNSS receiver stations recorded continuous electron density perturbations during these days. Apart from the ionospheric TEC perturbations, significant enhancements and decreases in daily maximum VTEC values over the four GNSS receiver stations were also noted. These were attributed to the changes in the atmospheric electric fields generated by the SDS event. The VTEC plots for each day exhibited similar trends, hence exhibited the same ionospheric dynamics. VTEC depletions of depths 3 to 6 TECU over all the four GNSS receiver stations were noted on 12^th, 14^th, 17^th, 20^th and 25^th June 2020. Nighttime VTEC enhancements were also noted and majorly occurred between 20:00 and 21:00 UT on 9^th, 13^th, 15^th, 17^th, 19^th, 20^th and 21^st June 2020. This was attributed to the development of the electron avalanche processes including dust and electron absorption or losses and the active conversion to electron dissociative attachment leading to electron excitation. In conclusion, the Godzilla SDS of June 2020 led to the electron density perturbations over Morocco.

This work focuses on the theoretical study of the effect of entanglement in the Yttrium Barium Copper Oxide (YBCO) superconductor on the critical current density, critical magnetic field, and penetration depth. Using the Ginzburg Landau (GL) theory, the expression for the GL coherence length, the critical current density, the lower critical magnetic field (Hc1), and the upper critical magnetic field (Hc2) for the entangled superconducting YBCO was obtained. At zero external magnetic fields, YBCO was found to undergo a transition from the normal state to the superconducting state at 93K and returned to normal. We found a direct relationship between the GL coherence length penetration depth and the temperature of the entangled superconducting YBCO. The graphs of the lower critical magnetic field (Hc1) and critical current density against temperature show a non-linear dependence.In contrast, the graph of the upper critical magnetic field (Hc2) against temperature (T) shows the linear dependence, which is in agreement with existing theoretical observations. On the other hand, the graph of critical current density against the distance of separation between the entangled electrons that form a cooper pair showed that the critical current density increases between 1.8 and 6 nanometers attaining a constant value after reaching 7 nanometers for infinite distances. Finally, for lower critical fields, the magnetic field decreases between 1.5 to 6 nanometers attaining a constant value of the magnetic field, for infinite values of distance of separation between the entangled pair of electrons.