Abstract

Solar protons in eruptive flares are stochastically accelerated in a wide spatial angle, and then they are effectively kept behind the expanding coronal mass ejection (CME) front, which can either bring protons to the magnetic-field line going to a remote observer or carry them away. We consider 13 solar proton events of cycle 24 in which protons with energy E > 100 MeV were recorded and were accompanied by the detection of solar hard X-ray (HXR) radiation with E > 100 keV by an ACS SPI detector and γ-radiation with E > 100 MeV by the FermiLAT telescope with a source in the western hemisphere of the Sun. The first arrival of solar protons into the Earth’s orbit was determined in each event by a significant “proton” excess over the ACS SPI background during or after the HXR burst. All events were considered relative to our chosen zero time (0 min) of parent flares. The “early” arrival of protons to the Earth’s orbit (<+20 min), which was observed in four events, corresponds to the “fast” acceleration of electrons (10 MeV/s). The “late” arrival of protons (>+20 min) corresponds to the “slow” acceleration of electrons (1 MeV/s) and was observed in six events. In three events, a “delayed” arrival of protons (>+30 min) was observed, when the CME propagation hindered the magnetic connection of the source with the observer. The direction of CME propagation is characterized in the catalog (SOHO LASCO CME Catalog) by the position angle (PA). The observed PA systematizes the times of the first arrival of protons and the growth rate of their intensity. The PA parameter should be taken into account in the analysis of proton events.

中文翻译：

---

太阳质子随机加速期间和之后的日冕传播

摘要

爆发性耀斑中的太阳质子在宽空间角内随机加速，然后有效地保持在不断扩大的日冕物质抛射 (CME) 前沿的后面，这可以将质子带到磁场线上，到达远程观测者或携带它们离开。我们考虑了第 24 周期的 13 个太阳质子事件，其中记录了能量E > 100 MeV 的质子，并伴随着 ACS SPI 探测器检测到E > 100 keV 的太阳硬 X 射线 (HXR) 辐射和 γ 辐射与电子> 100 MeV，由源在太阳西半球的 F​​ermiLAT 望远镜测得。在每次事件中，太阳质子首次到达地球轨道是由 HXR 爆发期间或之后超过 ACS SPI 背景的显着“质子”过量决定的。所有事件都被认为是相对于我们选择的父耀斑零时间（0 分钟）。在四个事件中观察到质子“提前”到达地球轨道（<+20 分钟）对应于电子的“快速”加速（10 MeV/s）。质子的“延迟”到达（>+20 分钟）对应于电子的“缓慢”加速（1 MeV/s），并在六个事件中被观察到。在三个事件中，当 CME 传播阻碍了源与观察者的磁连接时，观察到质子“延迟”到达（>+30 分钟）。CME 传播方向在目录 (SOHO LASCO CME Catalog) 中由位置角 (PA) 表征。观察到的 PA 将质子首次到达的时间及其强度的增长率系统化。在分析质子事件时应考虑 PA 参数。