On 2011 May 30 , quasi-periodic fast propagating ( QFP ) magnetosonic waves accompanied by a C2.8 flare were directly imaged by the Atomospheric Imaging Assembly instrument on board the Solar Dynamics Observatory .
The QFP waves successively emanated from the flare kernel , they propagated along a cluster of open coronal loops with a phase speed of \sim 834 km s ^ { -1 } during the flare ’ s rising phase , and the multiple arc-shaped wave trains can be fitted with a series of concentric circles .
We generate the k – \omega diagram of the Fourier power and find a straight ridge that represents the dispersion relation of the waves .
Along the ridge , we find a lot of prominent nodes which represent the available frequencies of the QFP waves .
On the other hand , the frequencies of the flare are also obtained by analyzing the flare light curves using the wavelet technique .
The results indicate that almost all the main frequencies of the flare are consistent with those of the QFP waves .
This suggests that the flare and the QFP waves were possibly excited by a common physical origin .
On the other hand , a few low frequencies revealed by the k – \omega diagram can not be found in the accompanying flare .
We propose that these low frequencies were possibly due to the leakage of the pressure-driven p –mode oscillations from the photosphere into the low corona , which should be a noticeable mechanism for driving the QFP waves observed in the corona .