标题： L1点处王-石-阿吉太阳风模型产生误差的原因是什么？ 显示英文标题

标题： What Causes Errors in Wang-Sheeley-Arge Solar Wind Modeling at L1 ?

摘要： 先前的背景太阳风（SW）验证研究已经报告了在L1点处建模和观测到的SW条件之间的差异。他们指出，这些差异的主要来源之一是我们如何建模太阳日冕。因此，提高预测能力需要对日冕建模进行彻底的研究。Wang-Sheeley-Arge（WSA）模型一直是提供近太阳SW条件的工作模型。其中一个重要组成部分是位势场源表面（PFSS）模型。 本研究分析了15个不同的卡林顿旋转（CR），并详细分析了CR 2052，以识别导致地球成功和错误SW预测的WSA模型设置。对于所研究的事件，我们显示增加模型网格分辨率可以改善开闭边界识别。这有助于更好地预测高速流（HSSs）的开始和持续时间。此外，我们发现优化后的源表面高度（R$_{ss}$）（位于1.8-3.1 R$_{\odot}$之间）进一步提高了所研究事件中HSS预测的准确性。详细分析表明，R$_{ss}$的变化会改变相关日冕洞在太阳表面的大圆角距离（GCAD）图以及磁连接到地球子午线位置的足点位置。这些因素改变了近太阳SW速度，最终导致地球附近的风速不确定性。我们还研究了日冕洞观测在限制R$_{ss}$和地球SW解中的有用性，并强调了它们在指导选择用于改进L1点背景太阳风建模的磁图方面的未充分利用的价值。 显示英文摘要

摘要： Previous ambient solar wind (SW) validation studies have reported on discrepancies between modeled and observed SW conditions at L1. They indicated that a major source of discrepancies stems from how we model the solar corona. Thus, enhancing predictive capabilities demands a thorough examination of coronal modeling. The Wang-Sheeley-Arge (WSA) model has been a workhorse model that provides the near-Sun SW conditions. An important component of it is the Potential Field Source Surface (PFSS) model. This study analyzes 15 different Carrington Rotations(CRs), and presents detailed analysis of CR 2052 to identify WSA model settings that lead to successful and erroneous SW predictions at Earth. For the events studied, we show that increasing the models grid resolution improves the open-close boundary identification. This results in better predicting the onset and duration of high-speed streams (HSSs). In addition, we find an optimized source surface height (R$_{ss}$) (lying between 1.8-3.1 R$_{\odot}$) further enhances HSS prediction accuracy for the studied events. A detailed analysis shows that changes in R$_{ss}$, (a) changes the Great Circle Angular Distance (GCAD) maps (at the solar surface) of the associated coronal holes and (b) changes the foot-point locations of the magnetic connectivities to the sub-Earth locations. These factors change the near-Sun SW speed, that eventually leads to uncertainties in speeds near Earth. We also investigate the usefulness of coronal hole observations in constraining R$_{ss}$ and SW solutions at Earth, and highlight their underutilized value in guiding the selection of magnetic maps for improved ambient solar wind modeling at L1.