Curated sample of 56 galaxies shows inner DM densities align with NIHAO, FIRE-2 and EDGE simulations across six orders of stellar mass

The study assembled rotation curves and stellar-mass profiles for galaxies spanning 10^6 to 10^11 solar masses, deriving inner DM density slopes and core radii via Jeans modeling and Markov-chain Monte Carlo fits. Core sizes proved energetically feasible with 0.1–1 % supernova coupling, matching the scatter seen in NIHAO, FIRE-2 and EDGE runs. Extreme outliers previously cited as tension were traced to uncertain inclination or gas-mass assumptions rather than new physics.

Residual mismatches remain at the high-mass end, where some simulated haloes retain steeper central slopes than observed; this points to differences in stellar-halo mass relations rather than dark-matter microphysics. The work therefore reframes the small-scale CDM problems as largely solved by improved observational curation and modest feedback, not requiring warm or self-interacting dark matter.

Future IFU surveys with 30-m-class telescopes will test whether the remaining high-mass discrepancy shrinks when stellar masses are anchored by dynamical modeling instead of photometry alone. If the alignment persists, the result tightens the allowed parameter space for alternative dark-matter models to sub-percent core-formation efficiencies.