Abstract This study investigates the response of equatorial and low latitude ionosphere during an intense geomagnetic storm of 26 August 2018 (Dst min = −206 nT) using the TEC observations from two chains of GPS stations along 80° E and 120° E longitudes in the Asian sector. These GPS networks include Waltair and four IGS stations (SGOC, IISC, HYDE and LCK4) along 80° E and five IGS stations (SHAO, TCMS, CKSV, PIMO and PGEN) along 120° E longitudes. The [O]/[N2] observations from GUVI have also been used for the present study. Large positive storm effect is observed in the day-time TEC for three consecutive days starting from main phase until the late recovery phases of the storm (26th to 28th August 2018). Significant difference has been observed in TEC response between 80° E and 120° E longitudes particularly during the recovery phase of the storm which is further confirmed by GIM derived TEC. The equatorial ionization anomaly (EIA) exhibit strong enhancement around the anomaly crests during the main phase of the storm. This enhancement in the EIA crest is also evidenced in GIM CODE TEC maps. The positive storm effect during the main and recovery phases is mainly attributed to the eastward prompt penetration electric fields in addition to strongly enhanced ratio of thermosphere neutral composition i.e. [O]/[N2], the results of which are presented in this paper.

中文翻译：

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电离层对 2018 年 8 月 26 日地磁风暴的响应，使用 GPS-TEC 观测沿亚洲部分东经 80°和 120°

摘要 本研究利用沿 80°E 和 120°E 经度的两个 GPS 站链的 TEC 观测，调查了 2018 年 8 月 26 日强烈地磁风暴（Dst min = -206 nT）期间赤道和低纬度电离层的响应。亚洲部门。这些 GPS 网络包括沿 80° E 的 Waltair 和四个 IGS 站（SGOC、IISC、HYDE 和 LCK4）以及沿 120° E 经度的五个 IGS 站（SHAO、TCMS、CKSV、PIMO 和 PGEN）。来自 GUVI 的 [O]/[N2] 观测也已用于本研究。从主要阶段到风暴的后期恢复阶段（2018 年 8 月 26 日至 28 日），在白天 TEC 中连续三天观察到大的正风暴效应。在 80° E 和 120° E 经度之间观察到 TEC 响应的显着差异，特别是在风暴的恢复阶段，GIM 衍生的 TEC 进一步证实了这一点。在风暴的主要阶段，赤道电离异常（EIA）在异常波峰周围表现出强烈的增强。GIM CODE TEC 地图也证明了 EIA 波峰的这种增强。主要阶段和恢复阶段的正风暴效应主要归因于向东快速穿透的电场以及强烈增强的热层中性成分比值[O]/[N2]，本文给出了其结果。GIM CODE TEC 地图也证明了 EIA 波峰的这种增强。主要阶段和恢复阶段的正风暴效应主要归因于向东快速穿透的电场以及强烈增强的热层中性成分比值[O]/[N2]，本文给出了其结果。GIM CODE TEC 地图也证明了 EIA 波峰的这种增强。主要阶段和恢复阶段的正风暴效应主要归因于向东快速穿透的电场以及强烈增强的热层中性成分比值[O]/[N2]，本文给出了其结果。