Monodromy of stratified braid groups, II

The space of monic squarefree polynomials has a stratification according to the multiplicities of the critical points, called the equicritical stratification. Tracking the positions of roots and critical points, there is a map from the fundamental group of a stratum into a braid group. We give a complete determination of this map. It turns out to be characterized by the geometry of the translation surface structure on ${\mathbb{C}\mathbb{P}}^1$ induced by the logarithmic derivative $df\mathrm{/}f$ of a polynomial in the stratum.