About nuclear liquid boiling in core-collapse supernova explosions Dmytro Iakubovskyi (Bogolyubov Institute for Theoretical Physics, Kiev, Ukraine)

The evolution of the stalled supernova shock after core bounce. Conventional neutrino-driven «delayed shock» scenario:

The problem is its low efficiency (only 1-2% of electron (anti) neutrino luminosity is converted to kinetic energy, Bethe 1993, Janka 2001)! To explain the SN 1987A observed kinetic energy, one needs to radiate at least 50 foe during the shock revival (several hundred of msecs)! But there is the observational limitation! According to Bethe 1993, total energy, emitted in electron (anti) neutrinos from SN1987A, is only about 58 foe in first 2 seconds! Therefore, finding the method of increasing the efficiency is crucial!

The macroscopic bubbles of lighter phase 2 originate inside the phase 1, moving outwards due to gravitational force Boiling inside the PNS: schematic picture.

For fixed values p and T thermodynamic system tends to have the least value of Gibbs free energy The electron neutrinos (L) are tightly coupled to nuclear matter, so the third term do not vary during our phase transition. The second term is zero because of average electral neytrality, therefore, only the first term is important, including chemical potential of neutrons (B).

From that we obtain the condition of coexistence between phases 1 and 2: where we mark with 0 the values of parameters straight on coexistence line between two phases. Phase 1 will be metastable if Finally, the criterion for boiling to exist: It is possible to satisfy this criterion using at least one equation of state (Suraud 1985). Therefore, the boiling can exist inside the supernova core!

Consequences from supernova matter boiling: -The thickness of the boiling layer is km (at the radial coordinate 10 km); - total mass of boiling layer is M sun (at the same moment of time); -the bubbles accelerate to ~1000 km/sec during ~0.1 msec; - the temperature of the neutrinosphere increases by 3-10%; - there will be the additional pressure ~1-10 keV/fm 3 that diminish the accretion rate on the proto-neutron star.

Thank you for your attention!