Inferred mass, mass fraction, and depth of ⁵⁶Ni in PTF 10vgv for different explosion times. The ⁵⁶Ni mass M ₅₆ is inferred from Equation (6), and we only plot M ₅₆ and X ₅₆ for times at which the bolometric luminosity cannot be explained as a diffusive tail according to Figure 4. The mass fraction is estimated as X ₅₆ ≈ M ₅₆/Δ M _diff, where the diffusion depth is calculated according to Equation (8).