arXiv subjects

Karen Fiuza

Publications and source records attributed to Karen Fiuza.

3 recordsLinked to original sources

arXiv2004

Powerful gravitational-wave bursts from supernova neutrino oscillations

During supernova core collapse and bounce resonant active-to-active, as well as active-to-sterile, neutrino ($ν$) oscillations can take place. Over this phase weak magnetism increases antineutrino mean free paths, and thus its luminosity. Because oscillations feed mass-energy into the target $ν$ species, the large mass-squared difference between $ν$ states implies a huge amount of power to be given off as gravitational waves (GWs) due to the universal {\it spin-rotation} and the spin-magnetic coupling driven $ν$ anisotropic flow, which is coherent over the oscillation length. The spacetime strain produced is about two orders of magnitude larger than those from $ν$ difussion or neutron star matter anisotropies. GWs observatories as LIGO, VIRGO, GEO-600, TAMA-300, etc., can search for these bursts far out to the VIRGO cluster of galaxies.

astro-ph↗

arXiv2004

Neutrino Oscillations at Supernova Core Bounce Generate the Strongest Gravitational-Wave Bursts

During the core bounce of a supernova collapse resonant active-to-active ($ν_a \to ν_a$), as well as active-to-sterile ($ν_a \to ν_s$) neutrino ($ν$) oscillations can take place. Besides, over this phase weak magnetism increases antineutrino ($\barν$) mean free paths, and thus its luminosity. Because the oscillation feeds mass-energy into the target $ν$ species, the large mass-squared difference between species ($ν_a \to ν_s$) implies a huge amount of power to be given off as gravitational waves ($L_{\textrm{GWs}} \sim 10^{49}erg s$^{-1}$), due to anisotropic but coherent $ν$ flow over the oscillation length. This anisotropy in the $ν$-flux is driven by both the {\it universal spin-rotation} and the spin-magnetic coupling. The new spacetime strain estimated this way is still several orders of magnitude larger than those from $ν$ diffusion (convection and cooling) or quadrupole moments of the neutron star matter. This new feature turns these bursts the more promising supernova gravitational-wave signal that may be detected by observatories as LIGO, VIRGO, etc., for distances far out to the VIRGO cluster of galaxies.

astro-ph↗

arXiv2004

Strongest gravitational waves from neutrino oscillations at supernova core bounce

Resonant active-to-active ($ν_a \to ν_a$), as well as active-to-sterile ($ν_a \to ν_s$) neutrino ($ν$) oscillations can take place during the core bounce of a supernova collapse. Besides, over this phase, weak magnetism increases antineutrino ($\barν$) mean free paths, and thus its luminosity. Because the oscillation feeds mass-energy into the target $ν$ species, the large mass-squared difference between species ($ν_a \to ν_s$) 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 $ν$ flow over the oscillation length. This asymmetric $ν$-flux is driven by both the spin-magnetic and the {\it universal spin-rotation} coupling. The novel contribution of this paper stems from 1) the new computation of the anisotropy parameter $α\sim 0.1-0.01$, 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 $ν_s$ that can be resonantly produced during the flavor conversions makes it a good candidate for dark matter as suggested by Fuller et {\it al.} (2003). The new spacetime strain thus estimated is still several orders of magnitude larger than those from $ν$ 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.

astro-ph↗