Abstract Details


Name: Hirdesh Kumar
Affiliation: Instituto de Astrofísica de Canarias
Conference ID: TVS202510161
Title: Magnetoacoustic Shocks and Spectropolarimetric Signals in the He I triplet at 10830 A
Authors and Co-Authors: Tobias Felipe, Christoph Kuckein, Sergio Javier González Manrique, A. Asensio Ramos
Abstract Type: Contributory Presentation
Abstract: Sunspots host different kinds of magnetohydrodynamic waves. These waves play an important role in the dynamics of the solar atmosphere. Slow magnetoacoustic waves propagate into the higher solar atmosphere and dissipate their energy in the form of shocks. These shocks are commonly observed as a sawtooth pattern in the line-of-sight velocity signal. Using spectropolarimetric observations in the photospheric Si I 10827 A and the chromospheric He I 10830 A spectral lines acquired from the GRIS instrument installed at the GREGOR telescope, we analyse five different sunspots located near the disc center of the Sun. Hazel2 spectropolarimetric inversion code is used to extract the information of line-of-sight velocity and magnetic fields of the photosphere and chromosphere. During the different phases of the shocks, striking changes in circular polarization (Stokes V) are detected. They can be explained by remarkable changes in the longitudinal magnetic field or by strong gradients in the line-of-sight velocity signal. In this talk, I will discuss these two scenarios.