Observational Analysis of Sunspot Waves Associated with a M3.7 Flare

Nowadays, observational capabilities make it possible to study sunspot waves from the photosphere up to the corona. Waves above sunspots have also been shown to have a different behavior at different layers. However, it is still unclear about what determines detail properties of sunspot wave in the corona. Another interesting question is how a flare impact sunspot waves since several previous works had shown a possible relationship between flares and sunspot waves. In this work, we are aimed at discussing these two questions by studying sunspot waves which were found during a M3.7 flare with one flare ribbon had swept sunspot twice. Detail analysis, including time-distance map, Fourier transform and wavelet analysis, are applied to observations of different AIA channels respectively. The result shows that the direction of wave propagation is limited after flare while speed of waves seem to be faster. The distinctive behavior which only appears in time-distance maps of AIA 1600 is that obvious wave-like structures become visible just after one flare ribbon sweeping the sunspot, implying a potential relationship between sunspot waves and the associated flare. We conclude that a flare could impact sunspot waves by changing the magnetic configuration of sunspot which might limit the direction of waves propagation and/or excite new waves above sunspot.