A significant portion of transients measured by spacecraft at 1 AU does not
show the well-defined properties of magnetic clouds (MCs). Here, we propose a
new class of complex, non-MC ejecta resulting from the interaction of two CMEs
with different orientation, which differ from the previously studied
multiple-MC event. At 1 AU, they are associated with a smooth rotation of the
magnetic field vector over an extended duration and do not show clear signs of
interaction. We determine the characteristics of such events based on a
numerical simulation and identify and analyze a potential case in the
long-duration CME measured in situ in 2001 March 19-22. Such events may result
in intense, long-duration geo-magnetic storms, with sawtooth events, and may
sometimes be misidentified as isolated CMEs.
