Ionospheric irregularities and numerical simulation of plasma bubbles

• Grant number: 10/05698-8
• Support Opportunities: Research Grants - Visiting Researcher Grant - International
• Start date: September 13, 2010
• End date: September 12, 2011
• Field of knowledge: Physical Sciences and Mathematics - Geosciences - Geophysics
• Principal Investigator: Inez Staciarini Batista
• Grantee: Inez Staciarini Batista
• Visiting researcher: Alexander José Carrasco
• Visiting researcher institution: Universidad de los Andes, Colombia, Colombia
• Host Institution: Instituto Nacional de Pesquisas Espaciais (INPE). Ministério da Ciência, Tecnologia e Inovação (Brasil). São José dos Campos , SP, Brazil

Abstract

The term "spread F" has been used to identify the irregularities that occur in the ionospheric F region plasma density at equatorial and low latitudes, in general. At the equatorial F region the occurrence of these irregularities is restricted to nighttime and to the latitude interval between ±15° around the magnetic equator. The spread detected at the F layer traces, seen on ionograms after sunset, can be interpreted as signatures of the plasma bubbles or irregular structures at the F region base, which appear as a consequence of the rapid F layer rise. Various theoretical studies show that these irregularities are generated by instability processes present at the equatorial F region base.This work aims to simulate, through a numerical model, the development and tempora evolution of the plasma bubbles at the magnetic equator, and compare the numerical results with observational data obtained during the COPEX campaign. The basic equations used are the momentum equation for ions and electrons and the equation for the current density. The final equations to be solved are the equations for the electric potential for the plasma density variations in space and time. An ionospheric model for the initial perturbation at the F region base, that takes into account the electric field mapping between E and F regions, will be developed. This will allows us to determine a threshold value for the polarization electric field necessary to originate the irregular structures at the F region base that will trigger the plasma irregularities. The numerical simulation will demand the development of a computational code: the language used will be FORTRAN. The electric potential and the continuity equations will be solved using numerical methods such as Successive Over Relaxation (SOR) and Flux- Corrected Transport (FCT). (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

CARRASCO, A. J.; BATISTA, I. S.. Estimation of the initial amplitude of plasma bubble seed perturbation from ionograms. RADIO SCIENCE, v. 47, MAR 31 2012. (10/05698-8)

CARRASCO, A. J.; BATISTA, I. S.; ABDU, M. A.. Numerical simulation of equatorial plasma bubbles over Cachimbo: COPEX campaign. Advances in Space Research, v. 54, n. 3, p. 443-455, AUG 1 2014. (10/05698-8)