Abstract

The variations in the parameters of twice ionized helium ions He⁺⁺ of solar wind plasma during the passage of the front of the interplanetary shock are studied. Data taken from measurements by the Bright Monitor of Solar Wind (BMSW) installed onboard SPEKTR-R satellite were used to calculate the parameters of the He⁺⁺ ions: the speed, temperature, and absolute and relative density (helium abundance). It was found that the absolute density of He⁺⁺ ions behind the front of the interplanetary shock increases and that the relative density decreases. The average helium abundance behind the shock front was slightly less (by 9%) than that in the unperturbed region. The change in helium abundance correlated with the parameter θ_Bn: the lower the θ_Bn value is, the higher helium abundance decrease behind the front of the interplanetary shock.

中文翻译：

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He ++离子在行星际激波前部的行为

摘要

研究了在行星际激波前部通过期间太阳风等离子体的两次电离氦离子He ⁺⁺的参数变化。从安装在SPEKTR-R卫星上的太阳风明亮监测器（BMSW）的测量中获取的数据用于计算He ⁺⁺离子的参数：速度，温度以及绝对和相对密度（氦丰度）。发现行星际激波前部后面的He ⁺⁺离子的绝对密度增加，而相对密度降低。冲击锋面后面的平均氦气丰度比未受扰动区域的平均氦气丰度略低（降低了9％）。氦气丰度的变化与参数_θBn相关：_θBn值越低，行星际激波前部后面的氦丰度降低越大。