What process, potentially triggered in O/Ne/Mg white dwarfs nearing critical mass, can lead to the formation of a neutron star?

Answer

Electron capture (neutronization) followed by collapse

In some massive white dwarfs, crushing density can trigger electron capture (neutronization) in the core before fusion ignites, causing rapid collapse halted by neutron degeneracy pressure, resulting in a neutron star.

What process, potentially triggered in O/Ne/Mg white dwarfs nearing critical mass, can lead to the formation of a neutron star?
starsstellar evolutionastrophysicswhite dwarfBlack Dwarf