This proposal merges together attempts to observe two kinds of solar structures - solar microflares and network dynamic fibrils - which are planned to be investigated to address common open questions on their relevance for the heating and dynamics of the solar corona.
Due to their small sizes and fast dynamics microflares need analysis demanding high spatial resolution observations combined with good temporal cadence.
Our objective is to analyse the dynamics and plasma evolution during microflares by studying the chromospheric response to electron beam and/or conductive heating together with the transition region and coronal response combined with X-ray spectral analysis. The comparison of these observational data with theoretical predictions in the frame of electron-beam-driven and conductively driven chromospheric evaporation for individual microflares can help us to answer several open questions regarding microflares and the coronal heating.
Network dynamic fibrils (DFs) display in the chromosphere repetitive mass loading by acoustic shocks driven by the global oscillations in the underlying photosphere. This scenario assumes that considerable power of photospheric 5-min oscillations is concentrated at the bases of inclined magnetic fluxtubes giving rise to the chromospheric DFs.
Using H alpha filtergrams obtained by the Dutch Open Telescope we have shown that the DFs exhibit also significant variations in orientation, which are faster for shorter DFs. Recently, downflows and upflows occurring at the base and tops of mottles, respectively, were reported.
To explain this dynamic structure the magnetic reconnection as a potential driver of mottles was suggested.
As an extension of the works mentioned above, in this proposal we aim at identification of the center-to-limb variation of kinematic properties of dynamic fibrils and also center-to-limb variation of terminal wavelength shift of visibility of the fibrils and mottles in the H alpha line profile.
Thus, the spectral observations of chromosphere with the best, spatial and spectral resolution, are needed.
More details: campaign page: http://www.astro.sk/~choc/open/08_dot/08_dot.html