SOLARNET Conference: The Many Scales of the Magnetic Sun

Signatures of an impulsive jet in a small-scale magnetic tornado: Spectro-polarimetric observations of a dynamic photospheric small-scale magnetic vortex associated with a chromospheric swirl

Not scheduled

20m

Haus H, Telegrafenberg

Poster presentation 2) Small and large-scale magnetic features – from bright points to sunspots (Observations and Theory) Small and large-scale magnetic features – from bright points to sunspots (Observations and Theory)

Speaker

Ms Saida Milena Diaz Castillo (Leibniz-Institut für Sonnenphysik (KIS))

Description

High-resolution solar observations revealed the existence of small-scale swirling vortices in chromospheric intensity maps and velocity diagnostics. Frequently, vortices have been observed near magnetic flux concentrations, indicating a link between swirls and the evolution of the small-scale magnetic fields. Vortices were also studied with MHD numerical simulations of the solar atmosphere, revealing their complexity, dynamics, and magnetic nature. In particular, it has been suggested that the chromospheric swirling plasma motion is due to a rotating magnetic field structure, which again is driven by a photospheric vortex flow at its footprint. In this contribution, we present a complete and comprehensive description of a small-scale bright magnetic flux concentration affected by convective instability, which interacts with an intergranular vortex flow yielding the formation of a chromospheric swirl. Within a minute, it suffers a sudden further intensification and deformation occurring simultaneously with the observation of a Rapid Blue-shift Excursion - RBE as a chromospheric jet. We study observations taken with the CRisp Imaging SpectroPolarimeter (CRISP) instrument and the CHROMospheric Imaging Spectrometer (CHROMIS) at the 1m Swedish Solar Telescope (SST) in April 2019 as part of a SOLARNET access program. The data were taken at quiet-Sun disk-center, recording full Stokes photospheric maps in the Fe I line at 617nm, full Stokes data in the Ca II infrared triplet line at 854nm, and spectroscopic maps in the H$\alpha$ 656nm and Ca II K line at 393nm. Utilizing the multi-wavelength data and applying height-dependent Stokes inversion, local correlation tracking methods and wavelet analysis, we are able to study several atmospheric properties during the event lifetime, which allowed us to interpret the spatial and temporal connectivity between the photosphere and the chromosphere. We identified signatures of a rebound upflow in the magnetic flux concentration that eventually steepened, producing an acoustic shock wave that dissipated in the lower chromosphere, which seems to trigger the impulsive jet. Our analysis indicates that we have observed a rotating magnetic object reaching from the photosphere to the chromosphere affected by a propagating shock wave and by a subsequent dissipation process, exhibiting an impulsive jet.