Radiative efficiency f_acc versus mass accretion rate Ṁ_sc at the protostellar surface (top) and time since protostellar birth (bottom). Both panels show outcomes from a 1D spherical setup with different initial molecular cloud core masses using the PLUTO code. Also shown as black circles in both panels are data from a 1 M_⊙ 3D RAMSES simulation with an initial turbulent Mach number of 0.2. Each plot includes a top subplot with a linear f_acc axis ranging from 0 to 1. Typical constant values of f_acc used in the literature lie within the grey hatched region.