Using high temporal resolution optical data obtained from three-wavelength all-sky imagers over six winters continuously at Yellow River Station (78.92°N,11.93°E) in Arctic,we statistically investigated the dependence of location of poleward moving auroral forms (PMAFs) on the interplanetary magnetic field (IMF) B z and B y components as a function of MLT and MLAT under stable IMF conditions.It is found that more PMAFs occurred in lower latitude for Bz<0 and there was less evident IMF B y-related prenoon-postnoon asymmetry for Bz<0 than for Bz>0.We found that the PMAFs were distributed over a wide range of MLT when Bz<0,which indicates that the reconnection X-line might spread like an 'S' shape.However,during northward IMF,PMAFs were observed predominantly prenoon for IMF By>0 and postnoon for IMF By<0 associating with the effect of the high-latitude reconnection,which is largely consistent with the theoretical model of the convection flow.
