Relic Neutrino Energy Density and the Mass Budget: Omega_nu h^2 Across the Allowed Sum-of-Masses Range

For the minimum mass sum allowed by oscillation data, about 0.06 eV, relic neutrinos contribute Omega_nu h^2 = 0.00064, which is 0.54 percent of the dark matter density. At a sum of 0.12 eV the contribution doubles to 0.00129, and at 0.30 eV it reaches 0.00322. This paper derives the conversion between mass sum and density parameter from the number-density budget, tabulates the full allowed range, and identifies where the relic background stops being a trace component and starts to matter for structure formation budgets. The frame under study supplies no additional energy-density component in this sector, so the standard budget stands unchanged, a negative result for any hoped-for bounce contribution. All values are computed, not measured.