Neutrino signatures and the neutrino-driven wind in Binary Neutron Star Mergers

Details Neutrino signatures and the neutrino-driven wind in Binary Neutron Star Mergers Neutrino signatures and the neutrino-driven wind in Binary Neutron Star Mergers

2008-06-26

arxiv.org/abs/0806.4380v1

Astronomy and Astrophysics

Astrophysics

23 pages, 20 figures, 2 tables, submitted to ApJ, high resolution version of the paper available at http://hermes.as.arizona.e

Scientific paper

10.1088/0004-637X/690/2/1681

We present VULCAN/2D multi-group flux-limited-diffusion radiation hydrodynamics simulations of binary neutron star (BNS) mergers, using the Shen equation of state, covering ~100 ms, and starting from azimuthal-averaged 2D slices obtained from 3D SPH simulations of Rosswog & Price for 1.4 Msun (baryonic) neutron stars with no initial spins, co-rotating spins, and counter-rotating spins. Snapshots are post-processed at 10 ms intervals with a multi-angle neutrino-transport solver. We find polar-enhanced neutrino luminosities, dominated by $\bar{\nu}_e$ and ``$\nu_\mu$'' neutrinos at peak, although $\nu_e$ emission may be stronger at late times. We obtain typical peak neutrino energies for $\nu_e$, $\bar{\nu}_e$, and ``$\nu_\mu$'' of ~12, ~16, and ~22 MeV. The super-massive neutron star (SMNS) formed from the merger has a cooling timescale of ~1 s. Charge-current neutrino reactions lead to the formation of a thermally-driven bipolar wind with <$\dot{M}$> ~10$^{-3}$ Msun/s, baryon-loading the polar regions, and preventing any production of a GRB prior to black-hole formation. The large budget of rotational free energy suggests magneto-rotational effects could produce a much greater polar mass loss. We estimate that ~10$^{-4}$ Msun of material with electron fraction in the range 0.1-0.2 become unbound during this SMNS phase as a result of neutrino heating. We present a new formalism to compute the $\nu_i\bar{\nu}_i$ annihilation rate based on moments of the neutrino specific intensity computed with our multi-angle solver. Cumulative annihilation rates, which decay as $t^{-1.8}$, decrease over our 100 ms window from a few 10$^{50}$ to ~10$^{49}$ erg/s, equivalent to a few 10$^{54}$ to ~10$^{53}$ $e^-e^+$ pairs per second.

Affiliated with

Also associated with

No associations

Rating

Neutrino signatures and the neutrino-driven wind in Binary Neutron Star Mergers does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Neutrino signatures and the neutrino-driven wind in Binary Neutron Star Mergers, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Neutrino signatures and the neutrino-driven wind in Binary Neutron Star Mergers will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-691933