Gravitational Waves from Supernovae

• when a massive (> 1.4 solar masses) star burns out its nuclear fuel, the core of the star collapses into a neutron star.
• during the collapse, the atmosphere of the star is hurled explosively outward, creating a supernova.
• the collapse is though not to produce strong gravitational waves, since it is nearly axially symmetric.
• (bar mode) instabilities in the neutron fluid may deform the neutron star immediately after the collapse.
• neutron stars with bar mode instabilities produce much stronger gravitational waves.
• only approximate theoretical predictions of gravitational waveforms from neutron star cores are available.