White light images of coronal mass ejections (CMEs) are projections on the plane‐of‐sky (POS). As a result, CME kinematics are subject to projection effects. The error in the true (deprojected) speed of CMEs is one of the main causes of uncertainty to Space Weather forecasts, since all estimates of the CME time‐of‐arrival (ToA) at a certain location within the heliosphere require, as input, the CME speed. We use single viewpoint observations for 1,037 flare‐CME events between 1996 and 2017 and propose a new approach for the correction of the CME speed assuming radial propagation from the flare site. Our method is uniquely capable to produce physically reasonable deprojected speeds across the full range of source longitudes. We bound the uncertainty in the deprojected speed estimates via limits in the true angular width of a CME based on multiview‐point observations. Our corrections range up to 1.37–2.86 for CMEs originating from the center of the disk. On average, the deprojected speeds are 12.8% greater than their POS speeds. For slow CMEs (V_POS < 400 km/s) the full ice‐cream cone model performs better while for fast and very fast CMEs (V_POS > 700 km/s) the shallow ice‐cream model gives much better results. CMEs with 691–878 km/s POS speeds have a minimum ToA mean absolute error (MAE) of 11.6 h. This method, is robust, easy to use, and has immediate applicability to Space Weather forecasting applications. Moreover, regarding the speed of CMEs, our work suggests that single viewpoint observations are generally reliable.

中文翻译：

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使用有效加速模型评估日冕物质抛射速度对到达时间预测性能的投影校正

日冕物质抛射（CME）的白光图像是在天空平面（POS）上的投影。结果，CME运动学会受到投影效果的影响。真实错误（已投影）CME的速度是造成太空天气预报不确定性的主要原因之一，因为在日球内某个位置的CME到达时间（ToA）的所有估计都需要CME速度作为输入。我们对1996年至2017年之间的1,037个火炬CME事件使用单视点观测，并提出了一种假设来自火炬站点的径向传播的校正CME速度的新方法。我们的方法独特地能够在整个源经度范围内产生物理上合理的投影速度。我们基于多视点观测值，通过CME真实角度宽度的限制来限制投影速度估计中的不确定性。对于源自磁盘中心的CME，我们的更正范围为1.37–2.86。平均而言，投影速度比其POS速度大12.8％。V _POS  <400 km / s），完整的冰淇淋圆锥模型效果更好，而对于快速和非常快的CME（V _POS  > 700 km / s），浅冰淇淋模型效果更好。POS速度为691–878 km / s的CME的最小ToA平均绝对误差（MAE）为11.6 h。这种方法是鲁棒的，易于使用的，并且对太空天气预报应用具有直接的适用性。此外，关于CME的速度，我们的工作表明单视点观测通常是可靠的。