  We perform some experimental simulations in spherical symmetry and
axisymmetry to understand the post-shock-revival evolution of core-collapse
supernovae. Assuming that the stalled shock wave is relaunched by neutrino
heating and employing the so-called light bulb approximation, we induce shock
revival by raising the neutrino luminosity by hand up to the critical value,
which is also de- termined by dynamical simulations. A 15M_{sun} progenitor
model is employed. We incorporate nuclear network calculations with a
consistent equation of state in the simulations to account for the energy
release by nuclear reactions and their feedback to hydrodynamics. Varying the
shock-relaunch time rather arbitrarily, we investigate the ensuing long-term
evolutions systematically, paying particular attention to the explosion energy
and nucleosynthetic yields as a function of this relaunch time, or equivalently
the accretion rate at shock revival. We study in detail how the diagnostic
explosion energy approaches the asymptotic value and which physical processes
contribute to the explosion energy in what proportions as well as their
dependence on the relaunch time and the dimension of dynamics. We find that the
contribution of nuclear reactions to the explosion energy is comparable to or
greater than that of neutrino heating. In particular, recombinations are
dominant over burnings in the contributions of nuclear reactions. Interestingly
1D models studied in this paper cannot produce the appropriate explosion energy
and nickel mass simultaneously, overproducing nickels, whereas this problem is
resolved in 2D models if the shock is relaunched at 300-400ms after bounce.
