Second bounces of seismic signals from sunquakes: modelling and data

The 6 September 2017 X9.3 solar flare produced interesting magnetic field transients and a few seismic sources generating visible acoustic ripples in the quiet magnetic bay of the hosting active region.Zharkov et al (2020) for the first time presented observations of the second bounce of acoustic waves generated in the solar photosphere by one of the seismic sources. In this work we model the second skips using the ray-theory and simple models of magnetic fields of a sunspot. We want to understand how various parametrisations related to the local magnetic field, source locations and source movements can influence the behaviour of the first and second skips in time-distance plots. This work will help us to understand why the majority of sunquakes do not present second bounces; it may give us clues on how to look at observations in search for ripples and will help with backtracking information on seismic sources.