Chirality, Helicity, and Joy’s Law

Abstract

AbstractConnections between the morphology of filaments and the global topology of the sun’s magnetic field, are an important topic that seems ready for assembly into a coherent picture. We suggest that the chirality of mid-and high-latitude filaments described by Martin et al. is most easily understood if they form in evolved “Type 1” neutral lines within active region bipoles, rather than in the “Type 2” neutral lines formed at the boundaries between bipoles, where lower-latitude filaments tend to form. This interpretation removes the disagreement between filament chirality and the well-known tilt of bipolar active regions described by Joy’s law, which exists if the high-latitude filaments formed at Type 2 neutral lines. Dynamical explanation of these two observed regularities probably implies quantitative understanding of the processes that govern the sign and magnitude of the α and ѡ-effects in a solar dynamo.