We present an analytical model for the magnetic field perturbationsassociated with flux transfer events (FTEs) on the dayside magnetopause as afunction of the shear between the magnetosheath and magnetospheric magneticfields and the ratio of their strengths. We assume that the events areproduced by component reconnection along subsolar reconnection lines withtilts that depend upon the orientation of the interplanetary magnetic field(IMF), and show that the amplitudes of the perturbations generated duringsouthward IMF greatly exceed those during northward IMF. As a result, evenif the distributions of magnetic reconnection burst durations/eventdimensions are identical during periods of northward and southward IMForientation, events occurring for southward IMF orientations mustpredominate in surveys of dayside events. Two factors may restore thebalance between events occurring for northward and southward IMForientations on the flanks of the magnetosphere. Events generated on thedayside magnetopause during periods of southward IMF move poleward, whilethose generated during periods of northward IMF slip dawnward or duskwardtowards the flanks. Due to differing event and magnetospheric magnetic fieldorientations, events that produce weak signatures on the daysidemagnetopause during intervals of northward IMF orientation may producestrong signatures on the flanks.
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