Radially averaged profiles at t = 0.8 of the Evrard collapse test. Clockwise from the top left panel: profiles of density, entropy, artificial conductivity parameter α^C, and radial velocity. Curves with different line styles and colors refer to SPH runs performed using different kernels and with (AC) or without (NOAC) the AC term in the SPH energy equation. The black solid lines indicate the 1D PPM reference solution of Steinmetz & Mueller (1993).