Quasi-periodic EUV emission intensity perturbations are recorded in the solar corona by SDO/AIA. The perturbations are localised to a guiding structure, rooted in a flaring active region, and are time coincident with oscillations of a coronal loop and a CME interaction with the solar surface. Using imaging data the spatial and temporal evolution along the guiding structure is studied, and the behaviour of surrounding structures is investigated.
The series of guided intensity enhancements with a period of 1.8 minutes has been recorded at 171 Å. The start and end times are found to correlate with the oscillation of a neighbouring loop, which has a dominant period of 1.5 minutes between the main displacements/enhancements. The recorded start times are coincident with the CME plasmoid impact detected at 131 Å.
The rapidly-propagating intensity enhancements are interpreted as a series of guided fast magnetoacoustic waves (FWMs), which may be formed by dispersive evolution of a broadband FMW excited in the guiding structure, or a periodic driver of multiple FMWs.