2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/6816It is shown that the mass loss due to rotation-driven hydrodynamical instability during the catastrophic collapse of the star is small. Neutron star is formed with a large rotational kinetic energy and the spin-down takes place in the following life of neutron star as a pulsar.3 pagesAstrophysicstext