In this study, we evaluate a coronal mass ejection (CME) arrival prediction tool that utilizes the wide‐angle observations made by STEREO's heliospheric imagers (HI). The unsurpassable advantage of these imagers is the possibility to observe the evolution and propagation of a CME from close to the Sun out to 1 AU and beyond. We believe that by exploiting this capability, instead of relying on coronagraph observations only, it is possible to improve today's CME arrival time predictions. The ELlipse Evolution model based on HI observations (ELEvoHI) assumes that the CME frontal shape within the ecliptic plane is an ellipse and allows the CME to adjust to the ambient solar wind speed; that is, it is drag based. ELEvoHI is used to perform ensemble simulations by varying the CME frontal shape within given boundary conditions that are consistent with the observations made by HI. In this work, we evaluate different setups of the model by performing hindcasts for 15 well‐defined isolated CMEs that occurred when STEREO was near L4/5, between the end of 2008 and the beginning of 2011. In this way, we find a mean absolute error of between 6.2 ± 7.9 and 9.9 ± 13 hr depending on the model setup used. ELEvoHI is specified for using data from future space weather missions carrying HIs located at L5 or L1. It can also be used with near‐real‐time STEREO‐A HI beacon data to provide CME arrival predictions during the next ∼7 years when STEREO‐A is observing the Sun‐Earth space.

中文翻译：

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使用基于日光层成像观测的集合建模评估 CME 到达预测

在这项研究中，我们评估了日冕物质抛射 (CME) 到达预测工具，该工具利用 STEREO 的日光层成像仪 (HI) 进行的广角观测。这些成像仪无与伦比的优势是可以观察到 CME 从接近太阳到 1 天文单位及更远的演化和传播。我们相信，通过利用这种能力，而不是仅仅依靠日冕观测，有可能改进今天的 CME 到达时间预测。基于 HI 观测的椭圆演化模型 (ELEvoHI) 假设黄道平面内的 CME 锋面形状是椭圆形，并允许 CME 适应环境太阳风速；也就是说，它是基于阻力的。ELEvoHI 用于通过在与 HI 观察结果一致的给定边界条件内改变 CME 正面形状来执行集合模拟。在这项工作中，我们通过对 2008 年底和 2011 年初 STEREO 接近 L4/5 时发生的 15 个定义明确的孤立 CME 进行后报来评估模型的不同设置。通过这种方式，我们找到了一个均值之间的绝对误差6.2 ± 7.9和9.9 ± 13 小时取决于所使用的模型设置。ELEvoHI 被指定用于使用来自未来空间天气任务的数据，这些数据携带位于 L5 或 L1 的 HI。它也可以用近乎实时的STEREO-A HI用烽火数据在未来提供CME到来的预言〜 7年时，STEREO-A是观察太阳-地球空间。