Several kinds of instabilities are often observed in the solar wind. Langmuir waves have been observed using wideband plasma wave measurements on several spacecrafts such as the Galileo spacecraft. We studied the Langmuir wave instability event in the solar wind on 10 December 1990, during a solar maximum. On this date, highly structured bursts and Langmuir waves have been observed by the Galileo spacecraft. We used the dispersion relation in hot magnetized plasma to calculate the Langmuir wave instability properties. The properties of Langmuir wave instability are investigated and all physical parameters of interplanetary in around 1 AU are analyzed. The instability parameters, such as wave frequency, the thermal velocity and the damping rate are calculated. The results show that the damping rate of Langmuir waves increases with increasing the frequency of Langmuir waves. Also, the lowest damping rate decreases with increase in the wave normal angle. The results show that a good agreement between computational results and Langmuir waves has been observed by the Galileo spacecraft on 10 December 1990.

在太阳风中经常观察到几种不稳定性。在诸如伽利略号航天器等几种航天器上使用宽带等离子波测量已观察到了朗缪尔波。我们研究了1990年12月10日太阳最高峰期间太阳风中的朗缪尔波不稳定性事件。到目前为止，伽利略号航天器已经观测到高度结构化的爆发和朗缪尔波。我们使用热磁化等离子体中的色散关系来计算朗缪尔波的不稳定性。研究了朗缪尔波不稳定性的性质，并分析了约1 AU内行星际的所有物理参数。计算波频率，热速度和阻尼率等不稳定性参数。结果表明，朗格缪尔波的阻尼率随着朗格缪尔波频率的增加而增加。另外，最低阻尼率随着波法向角的增加而降低。结果表明，伽利略号航天器于1990年12月10日观测到了计算结果与Langmuir波之间的良好一致性。