Figure 4
SAR as a function of the mean particle size D for variable volumetric packing fraction 
including noninteracting case (
) and two values Ms = 200 emu/cm3 and 400 emu/cm3.
For low Ms = 200 emu/cm3 the dipolar interactions are weak and SAR does not depend on 
. The solid line represents the solutions by means of RT. (b): SAR vs. D for different packing fractions and the values of K = 3 × 105 erg/cm3 (curve set 1), 1.5 × 105 erg/cm3 (curve set 2) and 0.5 × 105 erg/cm3 (curves set 3). Calculations correspond to log-normal distributions of size and anisotropy constants both with standard deviations 0.1, spherically distributed anisotropy axes and field amplitude H0 = 300 Oe.
