The boundaries of the auroral oval and auroral electrojets are an important source of information for understanding the coupling between the solar wind and the near-earth plasma environment. Of these two types of boundaries the auroral electrojet boundaries have received comparatively little attention, and even less attention has been given to the connection between the two. Here we introduce a technique for estimating the electrojet boundaries, and other properties such as total current and peak current, from 1-D latitudinal profiles of the eastward component of equivalent current sheet density. We apply this technique to a preexisting database of such currents along the 105° magnetic meridian, estimated using ground-based magnetometers, producing a total of 11 years of 1-min resolution electrojet boundaries during the period 2000–2020. Using statistics and conjunction events we compare our electrojet boundary data set with an existing electrojet boundary data set, based on Swarm satellite measurements, and auroral oval proxies based on particle precipitation and field-aligned currents. This allows us to validate our data set and investigate the feasibility of an auroral oval proxy based on electrojet boundaries. Through this investigation we find the proton precipitation auroral oval is a closer match with the electrojet boundaries. However, the bimodal nature of the electrojet boundaries as we approach the noon and midnight discontinuities makes an average electrojet oval poorly defined. With this and the direct comparisons differing from the statistics, defining the proton auroral oval from electrojet boundaries across all local and universal times is challenging.

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极光椭圆代理与极光电射流边界的比较

极光椭圆和极光电射流的边界是了解太阳风与近地等离子体环境之间耦合的重要信息来源。在这两种类型的边界中，极光电射流边界受到的关注相对较少，并且对两者之间的联系的关注更少。在这里，我们介绍了一种根据等效电流片密度东向分量的一维纬度剖面来估计电喷射边界以及其他属性（例如总电流和峰值电流）的技术。我们将该技术应用于沿 105° 磁子午线的此类电流的现有数据库，使用地面磁力计进行估计，在 2000 年至 2020 年期间产生总共 11 年的 1 分钟分辨率电射流边界。使用统计数据和合事件，我们将我们的电喷射边界数据集与基于群卫星测量的现有电喷射边界数据集以及基于粒子降水和场对准电流的极光椭圆代理进行比较。这使我们能够验证我们的数据集并研究基于电喷射边界的极光椭圆代理的可行性。通过这项研究，我们发现质子沉淀极光椭圆与电射流边界更加匹配。然而，当我们接近中午和午夜不连续点时，电喷射边界的双峰性质使得平均电喷射椭圆形的定义很差。由于这一点以及与统计数据不同的直接比较，从所有局部和宇宙时间的电喷射边界定义质子极光椭圆是具有挑战性的。