The problem
A massive star’s core can collapse while a shock pushes outward into the rest of the star. That shock can stall. What lets it move outward again and drive an explosion, and which stars fail to launch one? Neutrinos from the hot central remnant can heat surrounding matter; swirling gas can help this heating revive the shock.[1] [2]
A collapsing massive-star core launches a shock that can stall instead of expelling the star. Which conditions revive it, and can models predict outcomes across different starting structures?
The shock spends energy breaking up infalling nuclei. Neutrinos from the hot central remnant deposit energy behind it. This neutrino heating, aided by moving gas, can support expansion. But denser material falling inward also presses against the shock. A sharp density drop between stellar layers can ease that pressure, letting adequate heating drive expansion in simulations. Both the starting density profile and the neutrino treatment matter, so initial stellar mass alone is not a universal outcome rule.[1] [2]
Scope
A predictive physical account of shock revival and explosion outcomes across massive-star core collapse, including neutrino heating and multidimensional flow.
What remains open
Why it matters
An explosion throws some stellar material into surrounding space; matter that falls back can instead enlarge the remnant. The outcome helps determine which elements reach a galaxy’s gas and which stay in its compact remnants.[1]
A revived shock heats stellar layers, changing their composition through nuclear reactions, and expels some of that material. Other material can fall back into the remnant, a process called fallback. Predicting that division connects the observed remnant population with the chemical enrichment of galactic gas, rather than treating element ejection independently of the explosion.[1]
Definitions
3 terms
Shock
A moving compression front. During core collapse its energy losses and gains determine whether it continues outward to help expel stellar material.[1] [2]
Sources
- The physics of Core-Collapse Supernovae: explosion mechanism and explosive nucleosynthesis
Notes on The physics of Core-Collapse Supernovae: explosion mechanism and explosive nucleosynthesis
Researcher-authored review explains collapse, stalled-shock heating and element ejection while retaining stellar/model uncertainties.
- Core-Collapse Supernovae and their Gravitational Wave Signals: The Status of Theory and Modeling
Notes on Core-Collapse Supernovae and their Gravitational Wave Signals: The Status of Theory and Modeling
2026 review manuscript describes neutrino heating and multidimensional flow, with model uncertainties; gravitational waves remain a prospective diagnostic.