Spatial distribution of the ejecta of the BLh_q1.49 model after 1 day. Top-left quadrant: electron fraction at the beginning of the SNEC simulation. Top-right quadrant: mass fraction of ⁵⁶Ni. Bottom-left quadrant: initial entropy at the beginning of the SNEC simulation. Bottom-right quadrant: local heating rate. The magenta line indicates the position of the photosphere. Regions with Y_e ≳ 0.48 and s ≲ 50k_B/baryon produce a large amount of ⁵⁶Ni, which has a significant impact on the heating rate on the timescale of days.