Comment on “Non-Interacting Coronal Mass Ejections and Solar Energetic Particles Near the Quadrature Configuration of Solar Terrestrial Relations Observatory”

Aims. The expression for the shock Mach number used by Ravishankar and Michalek (2020) is incorrect. We wish to provide themwith a correct expression so they can redo their analyses.Methods. CME shocks are fast magnetosonic shocks and not intermediate Alfvén shocks. We give the steps for calculating the shocknormal, shock velocity and thus, the shock Mach number.We also mention that the shock properties, such as being quasiperpendicularor quasiparallel, is another important parameter for shock acceleration of energetic particles.Results. We have corrected the errors existing in the Astronomy and Astrophysics literature concerning the mathematical expressionfor the Mach number for a CME shock. Hopefully future authors of A&A papers will use the now correct expression for the Machnumber.Conclusions. The correct shock Mach number expression have been given to Ravishankar and Michalek. It is hopeful that they willredo their calculations (including using other shock properties) to see if their 2020 conclusions still hold true or not.

研究目的：拉维尚卡尔（Ravishankar）与米查莱克（Michalek）2020年的研究中所使用的激波马赫数表达式存在错误，我们旨在为其提供正确的表达式，使其能够重新开展相关分析工作。
研究方法：日冕物质抛射（Coronal Mass Ejection, CME）激波属于快速磁声激波，而非中间阿尔芬激波。我们给出了计算激波法向、激波速度，进而推导激波马赫数的完整步骤。此外我们还指出，激波的准垂直或准平行属性，是高能粒子激波加速过程中的另一项重要参数。
研究结果：我们修正了《天文学与天体物理学》（Astronomy and Astrophysics，简称A&A）相关文献中关于日冕物质抛射激波马赫数的数学表达式错误，期望未来《A&A》期刊的论文作者能够采用当前正确的马赫数表达式。
研究结论：我们已将正确的激波马赫数表达式提供给拉维尚卡尔与米查莱克，期望他们能够重新开展相关计算（包括纳入其他激波属性参数），以验证其2020年所得结论是否依然成立。