What is the mechanism that creates the extremely luminous Type II core-collapse supernova explosion?

Answer

The sudden, catastrophic halting and rebound of the inward-falling core

As the core collapses inward at high speed and compresses matter to nuclear density, the halt causes a powerful rebound, generating an outward-moving shock wave that causes the brilliant explosion.

What is the mechanism that creates the extremely luminous Type II core-collapse supernova explosion?
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