论文标题
Lhaaso-km2a在2021年6月10日的雷暴中检测到的宇宙射线阵雨的通量变化
Flux Variations of Cosmic Ray Air Showers Detected by LHAASO-KM2A During a Thunderstorm on 10 June 2021
论文作者
论文摘要
大型高空空气淋浴天文台(Lhaaso)有三个子阵列KM2A,WCDA和WFCTA。通过分析2021年6月10日雷暴中的KM2A数据,研究了宇宙射线空气淋浴的通量变化。在大气电场中,满足触发条件的淋浴事件的数量显着增加,最大分数增加了20%。发现触发速率的变化(增加或减小)在很大程度上取决于主要的天顶角。随着淋浴事件的类似趋势,次级颗粒的通量显着增加。为了更好地了解观察到的行为,使用Corsika和G4KM2A(基于Geant4的代码)进行蒙特卡洛模拟。我们发现,假设在观测水平以上的大气中存在均匀的向上电场,实验数据(在饱和的负场中)与模拟非常吻合,厚度为1500 m。由于大气电场的加速/减速和挠度,能量高于检测器阈值的二次颗粒的数量被修改,从而导致淋浴检测率的变化。
The Large High Altitude Air Shower Observatory (LHAASO) has three sub-arrays, KM2A, WCDA and WFCTA. The flux variations of cosmic ray air showers were studied by analyzing the KM2A data during the thunderstorm on 10 June 2021. The number of shower events that meet the trigger conditions increases significantly in atmospheric electric fields, with maximum fractional increase of 20%. The variations of trigger rates (increases or decreases) are found to be strongly dependent on the primary zenith angle. The flux of secondary particles increases significantly, following a similar trend with that of the shower events. To better understand the observed behavior, Monte Carlo simulations are performed with CORSIKA and G4KM2A (a code based on GEANT4). We find that the experimental data (in saturated negative fields) are in good agreement with simulations, assuming the presence of a uniform upward electric field of 700 V/cm with a thickness of 1500 m in the atmosphere above the observation level. Due to the acceleration/deceleration and deflection by the atmospheric electric field, the number of secondary particles with energy above the detector threshold is modified, resulting in the changes in shower detection rate.