Context. Recent progress in instrumentation enablessolar observations with high resolution simultaneously in the spatial,temporal, and spectral domains. Aims. We use such high-resolution observations tostudy small-scale structures and dynamics in the chromosphere of thequiet Sun. Methods. We analyse time series of spectral scansthrough the Ca Results. ii 854.2nm spectralline obtained with the CRISPinstrument at the Swedish 1-mSolar Telescope. The targets are quiet Sun regions inside coronal holesclose to disc-centre. Conclusions. The line core maps exhibit relativelyfew fibrils compared to what is normally observed in quiet Sun regionsoutside coronal holes. The time series show a chaotic and dynamic scenethat includes spatially confined ``swirl'' events. These events featuredark and bright rotating patches, which can consist of arcs, spiralarms, rings or ring fragments. The width of the fragments typicallyappears to be of the order of only02, which is close to theeffective spatial resolution. They exhibit Doppler shifts of -2 to-4kms-1 but sometimes up to-7kms-1, indicating fastupflows. The diameter of a swirl is usually of the order of2.Atthe location of these swirls, the line wing and wide-bandmaps show close groups of photospheric bright points that move withrespect to each other. Arg5. A likely explanation is that the relativemotion of the bright points twists the associated magnetic field in thechromosphere above. Plasma or propagating waves may then spiral upwardsguided by the magnetic flux structure, thereby producing the observedintensity signature of Doppler-shifted ring fragments. Key words: Sun: atmosphere - Sun:chromosphere - Sun: magnetic fields
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