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We use cosmological hydrodynamical galaxy formation simulations from theNIHAO project to investigate the response of cold dark matter (CDM) haloes tobaryonic processes. Previous work has shown that the halo response is primarilya function of the ratio between galaxy stellar mass and total virial mass, andthe density threshold above which gas is eligible to form stars, $n [{\rmcm}^{-3}]$. At low $n$ all simulations in the literature agree that dwarfgalaxy haloes are cuspy, but at high $n\ge 100$ there is no consensus. We tracehalo contraction in dwarf galaxies with $n\ge 100$ reported in some previoussimulations to insufficient spatial resolution. Provided the adopted starformation threshold is appropriate for the resolution of the simulation, weshow that the halo response is remarkably stable for $n\ge 5$, up to thehighest star formation threshold that we test, $n=500$. This free parameter canbe calibrated using the observed clustering of young stars. Simulations withlow thresholds $n\le 1$ predict clustering that is too weak, while simulationswith high star formation thresholds $n\ge 5$, are consistent with the observedclustering. Finally, we test the CDM predictions against the circularvelocities of nearby dwarf galaxies. Low thresholds predict velocities that aretoo high, while simulations with $n\sim 10$ provide a good match to theobservations. We thus conclude that the CDM model provides a good descriptionof the structure of galaxies on kpc scales provided the effects of baryons areproperly captured.

NIHAO -- XXV. Convergence in the cusp-core transformation of cold dark matter haloes at high star formation thresholds