Normalized flux density profiles of an adiabatically expanding plasma cloud as a function of radius for all frequencies. The continuous flux profiles use the expressions given in Yusef-Zadeh et al. (2008), with a particle spectral index of 1 as was determined to be the best-fitting value in that work. Note that the initial radius used by Yusef-Zadeh et al. (2008) (~3 Schwarzschild radii) is different from the initial radius that follows from using the size-frequency relation (~11 Schwarzschild radii).