Department of Meteorology, University of Reading, P.O. Box 243, Reading, Berkshire RG6 6BB, United Kingdom.
Phys Rev Lett. 2014 Jun 6;112(22):225001. doi: 10.1103/PhysRevLett.112.225001. Epub 2014 Jun 2.
Solar energetic particles (SEPs) occasionally contribute additional atmospheric ionization beyond that arising from the usual galactic cosmic ray background. During an SEP event associated with a solar flare on April 11, 2013, the vertical ionization rate profile obtained using a balloon-borne detector showed enhanced ionization with a 26% increase at 20 km, over Reading, United Kingdom. Fluctuations in atmospheric electrical parameters were also detected at the surface, beneath the balloon's trajectory. As no coincident changes in geomagnetism occurred, the electrical fluctuations are very likely to be associated with increased ionization, as observed by the balloon measurements. The lack of response of surface neutron monitors during this event indicates that energetic particles that are not detected at the surface by neutron monitors can nevertheless enter and influence the atmosphere's weather-generating regions.
太阳高能粒子（SEPs）偶尔会增加大气电离度，超过通常的银河宇宙射线背景。在 2013 年 4 月 11 日与太阳耀斑相关的 SEP 事件中，使用气球携带的探测器获得的垂直电离率剖面显示，在英国雷丁 20 公里处的电离度增加了 26%。在气球轨迹下方的地表也检测到大气电参数的波动。由于没有发生地磁变化的巧合，这些电波动很可能与观测到的气球测量结果所显示的电离度增加有关。在此次事件中，表面中子监测器没有反应，这表明表面中子监测器未检测到的高能粒子仍能进入并影响大气的天气生成区域。
