Fig. 15From: Low-energy particle experiments–ion mass analyzer (LEPi) onboard the ERG (Arase) satelliteEnergy–time diagram of the count rate of \(\hbox {H}^{+}\), \(\hbox {O}^{+}/\hbox {N}^{+}\), and \(\hbox {He}^{+}\) observed by LEPi on May 28, 2017. Lm, AL, and Sym-H indices are also shown. AL and Sym-H indices indicate the strongest current intensity of westward auroral electrojets and a measure of geomagnetic disturbance, respectivelyBack to article page