Abstract Auroral streamers are important meso‐scale processes that transport plasma and magnetic energy and drive dynamic magnetosphere‐ionosphere (MI) coupling and space weather. Although streamers are typically studied using imagers sensitive to energetic (> ${ >} $1 keV) electron precipitation, such as all‐sky imagers, some are associated with low‐energy (< ${< } $1 keV) precipitation better captured by red‐line auroral emissions. This paper reports such streamer‐like red‐line auroras observed poleward of a black aurora and an auroral torch, associated with a magnetospheric electron injection and braking ion flows. Using conjugate space‐ground observations, quasilinear theory, and auroral forward modeling, we establish the first direct linkage between streamer‐like red‐line auroras and plasma sheet electron pitch‐angle scattering by time‐domain structures. These results underscore the importance of wave‐driven diffuse auroral processes in generating low‐energy auroral streamers, distinct from the conventional quasi‐electrostatic coupling paradigm.

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