Predictions of the impact of coronal mass ejections (CMEs) in the heliosphere mostly rely on cone CME models, whose performances are optimized for locations in the ecliptic plane and at 1 AU (e.g., at Earth). Progresses in the exploration of the inner heliosphere, however, advocate the need to assess their performances at both higher latitudes and smaller heliocentric distances. In this work, we perform 3‐D magnetohydrodynamics simulations of artificial cone CMEs using the EUropean Heliospheric FORecasting Information Asset (EUHFORIA), investigating the performances of cone models in the case of CMEs launched at high latitudes. We compare results obtained initializing CMEs using a commonly applied approximated (Euclidean) distance relation and using a proper (great circle) distance relation. Results show that initializing high‐latitude CMEs using the Euclidean approximation results in a teardrop‐shaped CME cross section at the model inner boundary that fails in reproducing the initial shape of high‐latitude cone CMEs as a circular cross section. Modeling errors arising from the use of an inappropriate distance relation at the inner boundary eventually propagate to the heliospheric domain. Errors are most prominent in simulations of high‐latitude CMEs and at the location of spacecraft at high latitudes and/or small distances from the Sun, with locations impacted by the CME flanks being the most error sensitive. This work shows that the low‐latitude approximations commonly employed in cone models, if not corrected, may significantly affect CME predictions at various locations compatible with the orbit of space missions such as Parker Solar Probe, Ulysses, and Solar Orbiter.

中文翻译：

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改善整个太阳圈高纬度日冕物质抛射的预测

对日冕中的日冕物质抛射（CME）影响的预测主要依赖于圆锥CME模型，其模型针对黄道面和1 AU（例如地球）的位置进行了优化。然而，在探索内部日球层的进展中，提倡有必要在较高纬度和较小日心距的情况下评估其性能。在这项工作中，我们使用欧洲日球预报信息资产（EUHFORIA）进行了人工圆锥CME的3D磁流体动力学模拟，研究了在高纬度发射的CME情况下圆锥模型的性能。我们比较使用常用的近似（欧几里得）距离关系和使用适当的（大圆）距离关系初始化CME所获得的结果。结果表明，使用欧几里得逼近法初始化高纬度CME会在模型内部边界处产生泪珠状的CME横截面，从而无法将高纬度圆锥CME的初始形状复制为圆形横截面。由于在内边界处使用不适当的距离关系而引起的建模误差最终会传播到日球区域。在高纬度CME的模拟中以及在高纬度和/或距太阳很小距离的航天器位置，误差最为明显，受CME侧面影响的位置对误差最敏感。这项工作表明，圆锥模型中通常采用的低纬度近似值，如果不进行校正，