N. Freij, E. M. Scullion, C. J. Nelson, S. Mumford, S. Wedemeyer-Böhm and R. Erdélyi

The detection of upwardly propagating waves channelling energy from the chromosphere to the low corona

Figure 1. The region of plasma analysed in this article sampled at 07 : 23 UT: An overview of the field-of-view (FOV) inferred by SST/CRISP and SDO/AIA consisting of: (a) SDO/AIA 170 nm, detailing the photosphere; (b) SST Hα 656.28 nm (line core) sampling the chromosphere; the (c) SDO/AIA 30.4 nm filter (TR); and the lower corona detailed by (d) SDO/AIA 17.1 nm. The white line on each image represents the slit used to construct the time-distance diagrams plotted in Fig. 3. The cyan lines outline each slit used to investigate UPW behaviour.


Understanding how the multi-million kelvin corona is heated to such extreme temperatures has so far proved difficult. Numerous mechanisms, including magnetohydrodynamic (MHD) waves have been suggested which could provide an explanation; however, no observations have yet tracked the direct propagation of a wave train from the lower into the upper solar atmosphere. Here, we present the first observation of wave-based energy transport from the chromosphere to the transition region (TR) and corona by upwardly propagating waves (UPWs) around a large magnetic field concentration. We propose that the amount of energy potentially deposited into the corona above active regions (ARs) by these waves could offer a realistic answer to the important question of how the corona is energised.

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Last Revised: 2014 October 23rd