Resonant active-to-active ( \nu _ { a } \rightarrow \nu _ { a } ) , as well as active-to-sterile ( \nu _ { a } \rightarrow \nu _ { s } ) neutrino ( \nu ) oscillations can take place during the core bounce of a supernova collapse . Besides , over this phase , weak magnetism increases antineutrino ( \bar { \nu } ) mean free paths , and thus its luminosity . Because the oscillation feeds mass-energy into the target \nu species , the large mass-squared difference between species ( \nu _ { a } \rightarrow \nu _ { s } ) implies a huge amount of energy to be given off as gravitational waves ( L _ { \textrm { GWs } } \sim 10 ^ { 49 } erg s ^ { -1 } ) , due to anisotropic but coherent \nu flow over the oscillation length . This asymmetric \nu -flux is driven by both the spin-magnetic and the universal spin-rotation coupling . The novel contribution of this paper stems from 1 ) the new computation of the anisotropy parameter \alpha \sim 0.1 - 0.01 , and 2 ) the use of the tight constraints from neutrino experiments as SNO and KamLAND , and the cosmic probe WMAP , to compute the gravitational-wave emission during neutrino oscillations in supernovae core collapse and bounce . We show that the mass of the sterile neutrino \nu _ { s } that can be resonantly produced during the flavor conversions makes it a good candidate for dark matter as suggested by Fuller et al . ( 2003 ) . The new spacetime strain thus estimated is still several orders of magnitude larger than those from \nu difussion ( convection and cooling ) or quadrupole moments of neutron star matter . This new feature turns these bursts the more promissing supernova gravitational-wave signal that may be detected by observatories as LIGO , VIRGO , etc. , for distances far out to the VIRGO cluster of galaxies .