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arXiv · 1911.06839

Estimation of Key Sunquake Parameters through Hydrodynamic Modeling and Cross-Correlation Analysis

John T. Stefan·Alexander G. Kosovichev
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Abstract

Sunquakes are one of the more distinct secondary phenomena related to solar flares, where energy deposition in the lower layers of the Sun's atmosphere excites acoustic waves easily visible in Helioseismic and Magnetic Imager (HMI) dopplergrams. We explore two possible sources of sunquakes in the context of the electron beam hypothesis: an instantaneous transfer of momentum and a gradual applied force due to flare eruption. We model the sunquake excitation and compare with five observed sunquake events using a cross-correlation analysis. We find that at least half the events studied are consistent with the electron beam hypothesis and estimate the energy required to excite the sunquakes to be within the range determined by previous studies.

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John T. Stefan, Alexander G. Kosovichev. 2020-06-17. Estimation of Key Sunquake Parameters through Hydrodynamic Modeling and Cross-Correlation Analysis. https://doi.org/10.3847/1538-4357%2Fab88ae

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