DOT Tomography of the Solar Atmosphere VII. Chromospheric Response to Acoustic Events

Abstract

We use synchronous movies from the Dutch Open Telescope sampling the G band, Ca II and Halpha with five-wavelength profile sampling to study the response of the chromosphere to acoustic events in the underlying photosphere. We first compare the visibility of the chromosphere in Ca II H and Halpha, demonstrate that studying the chromosphere requires Halpha data, and summarize recent developments in understanding why this is so. We construct divergence and vorticity maps of the photospheric flow field from the G-band images and locate specific events through the appearance of bright Ca II H grains. The reaction of the Halpha chromosphere is diagnosed in terms of brightness and Doppler shift. We show and discuss three particular cases in detail: a regular acoustic grain marking shock excitation by granular dynamics, a persistent flasher which probably marks magnetic-field concentration, and an exploding granule. All three appear to buffet overlying fibrils, most clearly in Dopplergrams. Although our diagnostic displays to dissect these phenomena are unprecedentedly comprehensive, adding even more information (photospheric Doppler tomography and magnetograms, chromospheric imaging and Doppler mapping in the ultraviolet) is warranted.

arXiv commentaccepted by Solar Physics

References in corpus (8)

• Dynamic Hydrogen Ionization
• High Resolution Observations and Modeling of Dynamic Fibrils
• Non-equilibrium hydrogen ionization in 2D simulations of the solar atmosphere
• Magnetoacoustic shocks as driver of quiet Sun mottles
• The origin of the reversed granulation in the solar photosphere
• DOT tomography of the solar atmosphere. IV. Magnetic patches in internetwork areas
• On the origin of solar oscillations
• On the fine structure of the quiet solar \Ca II K atmosphere

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