The maximum peak of the directional derivative of the SuperDARN convection flow has been proposed as a proxy for the open/closed magnetic field line boundary (OCB) and this has been evaluated using data from the ultraviolet imagers collected during the steady southward Interplanetary Magnetic Field (IMF) condition. However, the technique ignores the contribution of ionospheric vorticity in determining the peak of the directional derivative of SuperDARN convection flow. In this paper these effects have been considered when identifying the OCB in the night sector, calculated using the directional derivatives of SuperDARN convection flow during the active substorm interval which occurred on October 14, 2001. Statistical comparison of the latitudes of the OCB, as estimated from the peaks of the directional derivative of the SuperDARN convection flow, determined with and without considering the relative maxima and minima vorticity, and as provided by images taken by the two Far Ultraviolet (FUV) Spectral Imagers onboard the IMAGE spacecraft (SI-12 and SI-13) indicates that the modified approach of the directional derivative of the SuperDARN convection flow may be used as an OCB proxy during active geomagnetic activity.

SuperDARN 对流的方向导数的最大峰值已被提议作为开放/闭合磁场线边界 (OCB) 的代理，并且已使用来自稳定向南行星际磁场期间收集的紫外线成像仪的数据进行评估（ IMF) 条件。然而，该技术忽略了电离层涡度在确定 SuperDARN 对流的方向导数峰值方面的贡献。在本文中，在识别夜间区域的 OCB 时已经考虑了这些影响，使用 2001 年 10 月 14 日发生的活动亚暴间隔期间 SuperDARN 对流的方向导数计算。 OCB 纬度的统计比较，估计从 SuperDARN 对流的方向导数的峰值，