Ionospheric vertical plasma drift and electron density response during total solar eclipses at equatorial/low latitude

Abstract

Abstract The response of the vertical plasma drift ( V z ) and the electron density ( N m F 2 ) during different solar eclipses was investigated. The diurnal values of the direct scaled measurement of F 2 peak height and the one derived from M (3000) F 2 data, acquired over an equatorial/low‐latitude stations, have been used to determine the vertical plasma drift. The ionosphere during a solar eclipse is significantly affected by the E × B vertical drift; the large depletion of electron density at low altitudes can be transported to high altitudes through the plasma vertical drift. The loss in ionization density during the eclipse phase decreases the electron density, which was accompanied by rapid increase in h m F 2 . This deviation in the N m F 2 during eclipse compared to control days can be related to the increase in the loss rate due to recombination, as a result of reduction in thermal energy. However, the maximum reduction in N m F 2 is not synchronous with the time of maximum totality but some minutes later. The differences in the solar epochs may contribute to the observed relative changes in the ionospheric F 2 region behavior during the eclipse window. Lastly, it is very difficult to separate the influence of magnetic disturbances from solar eclipse. The deviation in N m F 2 is higher during magnetic disturbed days than the quiet day. The reverse is the case for h m F 2 observation. However, the N m F 2 variation increases with an increase in solar activity.