| Presentation Title: | Small-scale turbulence can heat the solar chromosphere in plage regions. |
| Author(s): | Juan Martínez-Sykora, Sam Evans, Bart De Pontieu, Meer Oppenheim, Yakov Dimant, Mats Carlsson. |
Abstract:
The chromosphere is the interface region between the solar surface and the multi-million-degree corona. It is critical to understand energy flows within and through this region. Yet, in the chromosphere, particularly in plage regions, radiative MHD models have difficulties reproducing chromospheric observables. In this study, we combine IRIS observations with radiative magnetohydrodynamic (MHD) numerical models and multi-fluid models to more accurately model energy flows in the chromosphere. Specifically, we observe that within plage regions, between flux concentrations, the optically thin O I chromospheric line observed by IRIS shows a large non-thermal broadening. Combining radiative MHD simulations with the linear theory behind the Thermal Farley Buneman instability (TFB), we show that TFB instability should occur in these regions. This will create small-scale (meter) turbulence, leading to heating and changes in the electric field, which, in turn, can explain the source of non-thermal broadening of the O I spectral line.