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Поисковые слова: meteors
Armagh Observatory

The Response of a 3D Solar Atmosphere to Wave-driven Jets

E. Scullion, R. Erdélyi, V. Fedun, J. G. Doyle


Fig. 17. The illustration captures the process leading to the formation of TR waves where spicular jets form.

Abstract

Global oscillations from the solar interior are, mainly, pressure-driven (p-modes) oscillations with a peak power of 5 minute period. These oscillations are considered to manifest in many phenomena in the lower solar atmosphere, most notably, spicules. These small-scale jets may provide the key to understanding the powering mechanisms of the transition region (TR) and lower corona. Here we simulate the formation of wave-driven (type-I) spicule phenomena in 3-D and the transmission of acoustic waves from the lower chromosphere and into the corona. The outer atmosphere oscillates in response to the jet formation, and in turn, we reveal the formation of a circular seismic surface wave which we name as a TRQ (Transition Region Quake). The TRQ forms as a consequence of an upward propelling spicular wave-train that repeatedly punctures and energizes the TR. The steep density gradient enables the TRQ to develope and radially fan outwards from the location where the spicular plasma column impinges the TR. We suggest the TRQ formation as a formidable mechanism in continuously sustaining part of the energy budget of the TR. We present a supporting numerical model which allows us to determine the level of energy dumping at the TR by upward propagating p-modes. Upon applying a wavelet analysis on our simulations we identify the presence of a chromospheric cavity which resonates with the jet propagation and leaves behind an oscillatory wake with a distinctive periodicity. Through our numerical analysis we, also, discover type-I spicule turbulence leading to a convection-based motion in the low corona.

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Last Revised: 2011 October 18th