Transient events in the solar photosphere at high spatial and temporal resolution

Abstract

The research presented in this thesis showcases some of the diverse and abundant transient events seen in observed and simulated magnetic and velocity ?elds in the solar photosphere. This thesis emphasizes the use and understanding of inversion codes to infer the magnetic and velocity ?elds from polarized spectral line pro?les. These techniques were applied to quiet sun as well as active region observations and simulations. The analysis of the small-scale magnetic ?eld evolution, as presented in Chapters II and III, sheds light on the evolution of the quiet sun magnetism. This brings us closer to understanding its dynamics and interplay with the weakly magnetized gas, which is suspected to be the root cause for the majority of the heat transfer from the photosphere into the chromosphere and corona. The data set studied in Chapter IV is intriguing as it shows the magnetic and velocity ?eld evolution during a ?are with high temporal cadence. The analysis of unusual Stokes pro?les connects the lower photosphere to the dynamics in the chromosphere and corona. The last chapter, Chapter V, shows that the comparison of highly realistic 3 D simulations with observations can tell us more about the underlying physical mechanisms of the observed spectral signatures. The study not only con?rms the validity of the theoretical model, but also exposes the violent, high-speed dynamics present in the photospheric granulation