Left: comparison of the mass density, ⁵⁶Ni mass fraction, and electron density for the 1D models used to build the 2D ejecta 2D-X1-X2b and 2D-X1-X2B. Right: same as Fig. 13, but now comparing the results for the hybrid model 2D-X1-X2b (bipolar ejecta with an enhanced ⁵⁶Ni mass fraction along the polar regions) and the hybrid model 2D-X1-X2B (bipolar ejecta with an enhanced explosion energy along the polar regions). In both models the angle β_1∕2 is 22.5 deg. (See Sect. 6.3 for discussion.)