Determine the sign of the large-scale magnetic field

Determine which of the alpha effect or beta effect determines the sign, or handedness, of the large-scale magnetic field during the very early dynamics of the dynamo.

Background

The paper compares alpha- and beta-effect models for reconstructing the large-scale magnetic field from DNS data. It finds that the beta effect dominates magnetic-field amplification and maintenance across the kinematic and nonlinear regimes, whereas the alpha effect becomes important primarily for sustaining saturation in the nonlinear regime.

The authors state that the sign or handedness of the large-scale field remains unresolved during the very early evolution. They attribute this ambiguity to the assumption that the alpha and beta formulations are based on a homogeneous and isotropic system, leaving open which coefficient determines the field's initial sign.

References

An investigation into the very early dynamics of $\alpha$ and $\beta$ effects leaves it as yet unclear which factor determines the sign (or handedness) of the large-scale magnetic field. This ambiguity arises because the $\alpha$ and $\beta$ formulations in this study fundamentally assume a homogeneous and isotropic system.

— Connecting Dynamo Theory with DNS Data: A Computational Analysis of α and \b{eta} Effects  (2609.09767 - Park, 9 Sep 2026) in Section Summary and Discussion