Abstrakt
Analyses of the vector magnetic field on solar magnetic structures led to the Jurčák criterion, an empirical law that connects a critical value of the vertical component of the magnetic field to the umbral magnetoconvective mode in stable sunspots. We study the evolution of the vertical component of the magnetic field (Bver) on evolving pores and the existence of an equivalent critical vertical magnetic value to provide steadiness.
Indeed, we find that areas with weak Bver are unstable and granulation takes over them. However, areas with strong Bver show longer lifetimes.