SOUSA, R. V.; http://lattes.cnpq.br/1699517976589477; SOUSA, Ramon Viana de.
Resumo:
This work aimed to objective calculate the speed of plasma bubbles's vertical
growth at Sao Joao do Cariri (7.4°S, 36.5 0 W, 12.25°S de dip latitude) for the
period September to November 2005. For this, we used the optical technique of
airglow Ol 630.0 nm. The Ol 630.0 nm is a red light from the atomic oxygen
thermosphere at an altitude around 250 km whose intensity is directly
proportional to the electron density (concentration of electrons). Because the
ionosphere plasma bubbles are regions where the electron density is greatly
reduced as compared to its neighborhood, the intensity of the Ol 630.0 nm
airglow also decreases in these regions. Thus, observing the intensity of the Ol
630.0 nm airglow can check the occurrence of ionospheric bubbles. The
intensity of the Ol 630.0 nm airglow can be observed by digital monochrome
images. Two applications were developed in the computer programming
language IDL 6.2, one to process the digital images and the other to calculate
the speed of vertical growth of plasma bubbles with greater precision. The
images analyzed in this work were recorded by an instrument called all-sky
imager operating in Sao Joao do Cariri. The general conclusions of this study
were the following: 1) the vertical growth velocity of plasma bubbles showed a
high variation the time interval observed each night, thereby having a high value
on its standard deviation (between 15 and 43 m/s), 2) the intensity of the
vertical growth rate of the bubbles is relatively higher during the period of high
solar activity, 3) observed that there is a strong correlation between the
magnitude of the pre-reversal vertical drift layer F, later afternoon, and the
intensity of the vertical growth velocity of plasma bubbles.