Vampire white dwarfs can form the universe's most extreme dead stars, scientists find

A team at ETH Zurich led by Laurenz Thümmler described the mechanism of accretion-induced collapse: a white dwarf made of oxygen, neon, and magnesium pulling matter from a companion star collapses into a neutron star. Conditions must be 'just right' — accretion rate in a narrow range, or nova flashes or stellar wind will disrupt the process.

• Neutron stars usually form from stars about 8 solar masses via supernova
• AIC requires an oxygen-neon-magnesium white dwarf — a rare minority
• Accretion rate must be neither low nor high — otherwise collapse will not occur
• Neutron-rich matter emerges at mid-latitudes, not along the rotation axis