SOLARNET Conference: The Many Scales of the Magnetic Sun

In November 2021, Solar Orbiter started its nominal mission phase. The remote sensing instruments, onboard the spacecraft, acquired scientific data during three observing windows surrounding the perihelion of the first orbit of this phase. The High Resolution Telescope (HRT) of the Polarimetric and Helioseismic Imager (SO/PHI) onboard the Solar Orbiter acquired a high-cadence dataset of an active region during the Nanoflares Solar Orbiter Observing Plan. The combination of the excellent polarimetric sensitivity of the instrument and absence of interference of the Earth’s atmosphere provide an ideal scenario to study the presence of MHD waves in the solar photosphere. A B-$\omega$ and phase-difference analyses are applied on the line of sight velocity, the circular polarization maps and other averaged quantities. We find that several MHD modes at different frequencies are excited in all analyzed structures. The results focus mainly on the leading sunspot and on a small pore in the same active region. The SO/PHI measurements clearly confirm the presence of magnetic and velocity oscillations compatible with one or more MHD wave modes in a pore and a sunspot. Improvements in modeling are still necessary to interpret the relation between fluctuations of different diagnostics.