of the cooling front as $$V_{\rm front}~=~{2\over 3}\alpha_0 \left( {H\over R} \right)^{N+1}
      {C_{\rm s}\over w}R,$$ where $H$ = $C_{\rm s}{\Omega}$ is the vertical scale height at radius $R$, C$_{\rm s}$ is the sound speed, $\Omega$ is the Keplerian angular velocity, $w$ is the width of the cooling front and the viscosity parameter is given by $\alpha$ = $\alpha_0(H/R)^N$. The results of our numerical models are in reasonable agreement with this expression for our assumed $\alpha$ prescription and logarithmic zoning. In the first 40 days after the maximum, the velocity of the cooling wave, $V_{\rm front}$, is almost the same in both the irradiated and the non-irradiated models, but slightly slower in the irradiated case. At later times, the cooling-wave speed in the irradiated model is somewhat faster than that for the non-irradiated case, although both become very slow, less than $10^3$ cm s$^{-1}$ after 100 days. The overall shapes of the velocity profiles are rather similar in both models.

Although a certain range has been explored, we have not undertaken a systematic parameter study of these computationally expensive irradiated models. Varying $C_{\rm X}$, ${\alpha}_0$, and $N$ gives different slopes of the light curves in the decay and different intervals between 