An Acoustic Model for Sunquakes Unifying the Solar Interior and Atmosphere
John Stefan, Alexander Kosovichev
Published: 2025/9/8
Abstract
One of the leading hypotheses for sunquake generation suggests that flare-accelerated particles originating from the reconnection site in the corona travel down to the chromosphere and photosphere, where they deposit energy through collisions and subsequently drive acoustic oscillations. To properly encompass this top-down excitation mechanism, we extend the domain of a semi-spectral 3D acoustic model of the global Sun up to several 10's of Mm above the photosphere, where the transition region and lower corona are resolved. We then use the radially-dependent heating rates derived from the flare radiative hydrodynamic (RADYN) simulations -- extrapolated to a 3D profile -- to realistically excite sunquakes. In addition to the usual sunquake wavefronts, we also observe waves that propagate through the chromosphere and corona in a similar fashion to Moreton-Ramsey waves and large-scale coronal propagating fronts (LCPFs). We examine the dynamics of these waves and discuss how they may be used to constrain models of sunquake excitation.