Partial regularity for variational integrals with Morrey-Hölder zero-order terms, and the limit exponent in Massari's regularity theorem

We revisit the partial ${\mathrm{C}}^{1,\alpha }$ regularity theory for minimizers of non-parametric integrals with emphasis on sharp dependence of the Hölder exponent $\alpha$ on structural assumptions for general zero-order terms. A particular case of our conclusions carries over to the parametric setting of Massari’s regularity theorem for prescribed-mean-curvature hypersurfaces and there confirms optimal regularity up to the limit exponent.