Fraction of modeled synchrotron emissivity of protostars recovered after accounting for SSA, FFA, and the RTE. The fractional emissivity at 144 MHz is shown as a function of ⟨B_⊥⟩ and N_e. The temperature of the ionized gas causing FFA is considered to be 10⁴ K. The extinction processes are averaged within 0.03 pc from the modeled protostar, or the LOFAR FWHM at the distance of Perseus. A vertical dash-dotted black line marks the estimated N_e value for our protostellar core sample.