Kebergantungan gelembung plasma khatulistiwa dan arus tentangan elektrojet di sektor barat Asia Tenggara

Abstract

At night, region near the equator were often disturbed by the presence of large scale wave structural known as the equatorial plasma bubble (EPB). Various studies have been carried out to find for the parameter that can control the formation of EPB including their relationship within the strength of the equatorial electrojet (EEJ) current. However, the EEJ current were often detected to reverse the direction to westward and manifests a depression in plot of H versus time in dip equator. This EEJ current reversal phenomenon is referred as counter electrojet (CEJ) current. Hence, this study was conducted to determine the dependency between EPBs and evening CEJ current in the western sector of Southeast Asian. The presence of CEJ currents have been analyzed by using EUEL index which were calculated fom the northern component of geomagnetic data from ground magnetometer station, Magnetic Data Acquisition System (MAGDAS). A single station approached at the equator and two station pairs were applied in this study to ensure accuracy of the electrojet data. The ground magnetometer stations involved were Langkawi (LKW) at Malaysia and Kototabang (KTB) at Indonesia. Additionally, this study also utilized data from the high-density Global Positioning System (GPS) receiver network in Southeast Asia to track the presence of EPB widely. In the end, the results showed that the higher the negativity value of the EUEL index (nT), the weaker the EPB structure were formed.