before any activity from the inner disk, soft X-rays from the inner optically thick disk or hard or soft X-rays from any coronal emission. This is consistent with the results of multi-wavelength observations of Nova Muscae (see Lund 1993). A prediction of the absolute times of peak emission in any band is more uncertain in the absence of reliable models for the time-dependent power-law emission.

 The Shadow Effect
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The non-monotonic distribution of the disk height causes the middle portions of the disk to block the flux of direct radiation emitted from near the inner edge of the disk, and thus prevent the direct irradiation of outer parts of the disk. The shadowing of the outer disk is determined by the radial distribution of the opening angle, $\tan\theta=H/R$, assuming the radiation to arise from an inner region of small $H$ and $R$. A region with a given value of $H/R$ will thus be shadowed by a region at smaller $R$ with larger $H/R$. Outer regions with small $H/R$ in the wake of an inward-propagating cooling wave will clearly be in the shadow of inner, hot regions.

[4]{} [20pc]{} [Shadow effect for the direct irradiation. The hatched part in the figure 