Dynamical Coupling of the Solar Subsurface Shear Layer and the Atmosphere

The dynamical coupling of subsurface and surface layers of the Sun is crucial for understanding how phenomena observed in the solar atmosphere reflect the evolution of subsurface plasma flows in the present global-scale rotation. In this work, we use long time-series (over 100-hours) of high-resolution 3D radiative hydrodynamic simulations obtained for an 80-Mm wide and 25-Mm deep computational domain, using the SolarBox code, to investigate the formation and dynamics of the Subsurface Shear Layer (SSL) and observational manifestations. The solar rotation is modeled in the f-plane approximation at 30 degrees latitude. The simulation results reveal the formation of the SSL, and meridional circulation. To compare the simulation results with the SDO/HMI observations, we generate synthetic time series of the Fe I (6173A) line profile for different locations on the solar disk, using the SPINOR radiative transfer code. The line-profile data are converted into the SDO/HMI observables using an HMI pipeline emulator and analyzed for both the modeled and instrumental resolutions. The analysis results reproduce the photospheric structure and dynamics as well as various helioseismic properties such as rotational frequency splitting, ring- and time-distance diagrams, and the center-to-limb effect. This work provides a basis for a deeper understanding of the solar subsurface dynamics and physical interpretation of observational data.