#sgrb annihilator

[florshedworf]

thunder respecting shiny’s new name seconds after he said it. a true ally

dialouge under cut:

Shiny: Shock and awe! Ohohoho. Maybe that can be my new call sign. “Shock and Awe”! Ooh, how about “Shock and Oooh.” Or, orrrr… “Annihilator.”

Thunder: Evolutions cruel inevitability has finally caught up to you, Thunder. And it is called… Annihilator.

[bgsartcavern]

Hey uhhhhh why would you do that to the boy

(Okay to reblog, do not repost.)

[arxt1]

A magnetar engine for short GRBs and kilonovae. (arXiv:2003.06043v4 [astro-ph.HE] UPDATED)

We investigate the influence of magnetic fields on the evolution of binary neutron-star (BNS) merger remnants via three-dimensional (3D) dynamical-spacetime general-relativistic (GR) magnetohydrodynamic (MHD) simulations. We evolve a postmerger remnant with an initial poloidal magnetic field, resolve the magnetoturbulence driven by shear flows, and include a microphysical finite-temperature equation of state (EOS). A neutrino leakage scheme that captures the overall energetics and lepton number exchange is also included. We find that turbulence induced by the magnetorotational instability (MRI) in the hypermassive neutron star (HMNS) amplifies magnetic field to beyond magnetar-strength ($10^{15}\, \mathrm{G}$). The ultra-strong toroidal field is able to launch a relativistic jet from the HMNS. We also find a magnetized wind that ejects neutron-rich material with a rate of $\dot{M}_{\mathrm{ej}} \simeq 1 \times10^{-1}\, \mathrm{M_{\odot}\, s^{-1}}$. The total ejecta mass in our simulation is $5\times 10^{-3}\, \mathrm{M_{\odot}}$. This makes the ejecta from the HMNS an important component in BNS mergers and a promising source of $r$-process elements that can power a kilonova. The jet from the HMNS reaches a terminal Lorentz factor of $\sim 5$ in our highest-resolution simulation. The formation of this jet is aided by neutrino-cooling preventing the accretion disk from protruding into the polar region. As neutrino pair-annihilation and radiative processes in the jet (which were not included in the simulations) will boost the Lorentz factor in the jet further, our simulations demonstrate that magnetars formed in BNS mergers are a viable engine for short gamma-ray bursts (sGRBs).

from astro-ph.HE updates on arXiv.org https://ift.tt/39SlhEt

[arxt1]

A magnetar engine for short GRBs and kilonovae. (arXiv:2003.06043v4 [astro-ph.HE] UPDATED)

We investigate the influence of magnetic fields on the evolution of binary neutron-star (BNS) merger remnants via three-dimensional (3D) dynamical-spacetime general-relativistic (GR) magnetohydrodynamic (MHD) simulations. We evolve a postmerger remnant with an initial poloidal magnetic field, resolve the magnetoturbulence driven by shear flows, and include a microphysical finite-temperature equation of state (EOS). A neutrino leakage scheme that captures the overall energetics and lepton number exchange is also included. We find that turbulence induced by the magnetorotational instability (MRI) in the hypermassive neutron star (HMNS) amplifies magnetic field to beyond magnetar-strength ($10^{15}\, \mathrm{G}$). The ultra-strong toroidal field is able to launch a relativistic jet from the HMNS. We also find a magnetized wind that ejects neutron-rich material with a rate of $\dot{M}_{\mathrm{ej}} \simeq 1 \times10^{-1}\, \mathrm{M_{\odot}\, s^{-1}}$. The total ejecta mass in our simulation is $5\times 10^{-3}\, \mathrm{M_{\odot}}$. This makes the ejecta from the HMNS an important component in BNS mergers and a promising source of $r$-process elements that can power a kilonova. The jet from the HMNS reaches a terminal Lorentz factor of $\sim 5$ in our highest-resolution simulation. The formation of this jet is aided by neutrino-cooling preventing the accretion disk from protruding into the polar region. As neutrino pair-annihilation and radiative processes in the jet (which were not included in the simulations) will boost the Lorentz factor in the jet further, our simulations demonstrate that magnetars formed in BNS mergers are a viable engine for short gamma-ray bursts (sGRBs).

from gr-qc updates on arXiv.org https://ift.tt/39SlhEt

[arxt1]

A magnetar engine for short GRBs and kilonovae. (arXiv:2003.06043v3 [astro-ph.HE] UPDATED)

We investigate the influence of magnetic fields on the evolution of binary neutron-star (BNS) merger remnants via three-dimensional (3D) dynamical-spacetime general-relativistic (GR) magnetohydrodynamic (MHD) simulations. We evolve a postmerger remnant with an initial poloidal magnetic field, resolve the magnetoturbulence driven by shear flows, and include a microphysical finite-temperature equation of state (EOS). A neutrino leakage scheme that captures the overall energetics and lepton number exchange is also included. We find that turbulence induced by the magnetorotational instability (MRI) in the hypermassive neutron star (HMNS) amplifies magnetic field to beyond magnetar-strength ($10^{15}\, \mathrm{G}$). The ultra-strong toroidal field is able to launch a relativistic jet from the HMNS. We also find a magnetized wind that ejects neutron-rich material with a rate of $\dot{M}_{\mathrm{ej}} \simeq 1 \times10^{-1}\, \mathrm{M_{\odot}\, s^{-1}}$. The total ejecta mass in our simulation is $5\times 10^{-3}\, \mathrm{M_{\odot}}$. This makes the ejecta from the HMNS an important component in BNS mergers and a promising source of $r$-process elements that can power a kilonova. The jet from the HMNS reaches a terminal Lorentz factor of $\sim 5$ in our highest-resolution simulation. The formation of this jet is aided by neutrino-cooling preventing the accretion disk from protruding into the polar region. As neutrino pair-annihilation and radiative processes in the jet (which were not included in the simulations) will boost the Lorentz factor in the jet further, our simulations demonstrate that magnetars formed in BNS mergers are a viable engine for short gamma-ray bursts (sGRBs).

from astro-ph.HE updates on arXiv.org https://ift.tt/39SlhEt