What Is The Expected Timescale For The Onset Of Non-linear Dynamo Action In A 2-3 Solar Mass Asymptotic Giant Branch Star, And How Might This Influence The Development Of Large-scale Magnetic Fields During The Subsequent Helium Flash Phase?

The expected timescale for the onset of non-linear dynamo action in a 2-3 solar mass asymptotic giant branch (AGB) star is on the order of a few thousand years. This process is driven by the vigorous convection and rotational dynamics of the star, enabling the rapid generation and amplification of magnetic fields.

During the subsequent helium flash phase, which occurs as part of a thermal pulse in the AGB phase, these pre-established magnetic fields can significantly influence the dynamics of the flash. The magnetic fields may suppress or modify convection patterns, leading to more ordered convective flows. This, in turn, can affect the transport of energy and material, potentially altering the duration or intensity of the flash. Additionally, the magnetic fields may provide pressure support and influence the star's rotation, impacting angular momentum transfer and the overall structure of the layers involved in the flash.

Thus, the presence of strong magnetic fields from the non-linear dynamo action can play a crucial role in shaping the characteristics of the helium flash during the thermal pulse, contributing to a more structured and coherent energy release process.