Karakteristik Equatorial Plasma Bubbles (EPB) dari Pengamatan Radar Atmosfer Equator (EAR) Dyah Rahayu Martiningrum

Abstract

Phenomena such as Equatorial Plasma Bubbles/Equatorial Spread F (EPB/ ESF) and the Equatorial Ionization Anomaly (EIA) was potentially occured in the Indonesian region of the upper atmosphere (ionosphere) located in the active zone ionosphere disturbances, that is in the range of + 15 latitude geomagnetic. These phenomena would disrupt the operation of radio and satellite communications systems in the form of a disturbance in the amplitude and phase of the received radio wave receivers on Earth, known as scintillation. In this study addressed several important characteristics observed by the Equatorial Atmosphere Radar system that has operated in Kototabang (0.20S, 100.32E; 10.36S dip lat). Radar antenna system is arranged so that is able to observe the ionosphere interference that occurs perpendicular to the magnetic field lines, is observed as a Field Aligned irregularities (FAI). From EAR data analysis obtained two types of plasma bubbles post-sunset and post-midnight which is driven by two kinds of different physical mechanisms. Seasonal variation of both plasma irregularities are discussed in this paper. In equinox months (March-April or September-October), post-sunset are frequently occurred rather than post-midnight. While in solstice months (December-January or June-July) post-midnight are frequently occurred. The propagation direction provide more detail explanation related to development of irregularities time by time horizontally and vertically. The results not only suggested the better understandings of mechanism of EPB/ESF occurrence, but also contributed on development of plasma instability model and supported observations by other instrument which have already operated.