Dayside poleward moving auroral forms and ionospheric convection under stable interplanetary magnetic field (IMF) conditions

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) Bzand Bycomponents 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 By-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.