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Related papers: Transport in neutron star mergers

200 papers

We study out-of-thermodynamic equilibrium effects in neutron star mergers with 3D general-relativistic neutrino-radiation large-eddy simulations. During merger, the cores of the neutron stars remain cold ($T \sim$ a few MeV) and out of…

In the violent post-merger of binary neutron-star mergers strong oscillations are present that impact the emitted gravitational-wave (GW) signal. The frequencies, temperatures and densities involved in these oscillations allow for…

General Relativity and Quantum Cosmology · Physics 2025-03-11 Michail Chabanov , Luciano Rezzolla

We analyze the isospin equilibration properties of neutrinoless nuclear ($npe$) matter in the temperature and density range that is relevant to neutron star mergers. Our analysis incorporates neutrino-transparency corrections to the isospin…

Nuclear Theory · Physics 2024-05-14 Mark G. Alford , Alexander Haber , Ziyuan Zhang

We consider transport properties of the hypernuclear matter in neutron star cores. In particular, we calculate the thermal conductivity, the shear viscosity, and the momentum transfer rates for np$\Sigma^{-}\Lambda e\mu$ composition of…

High Energy Astrophysical Phenomena · Physics 2021-06-24 Peter Shternin , Isaac Vidaña

Merging neutron stars are expected to produce hot, metastable remnants in rapid differential rotation, which subsequently cool and evolve into rigidly rotating neutron stars or collapse to black holes. Studying this metastable phase and its…

High Energy Astrophysical Phenomena · Physics 2021-03-19 Giovanni Camelio , Tim Dietrich , Stephan Rosswog , Brynmor Haskell

In this work, we estimate how much bulk viscosity driven by Urca processes is likely to affect the gravitational wave signal of a neutron star coalescence. In the late inspiral, we show that bulk viscosity affects the binding energy at…

The bulk viscosity of the neutron star matter due to the direct Urca processes involving nucleons, electrons and muons is studied taking into account possible superfluidity of nucleons in the neutron star cores. The cases of singlet-state…

Astrophysics · Physics 2009-05-13 P. Haensel , K. P. Levenfish , D. G. Yakovlev

Neutron star mergers are amongst the most promising sources for the joint detection of gravitational waves and electromagnetic signals. They are also potential sites for the production of r-process elements and probes of the equation of…

High Energy Astrophysical Phenomena · Physics 2026-05-29 Samantha Rath , Francois Foucart , Lawrence E. Kidder , Harald P. Pfeiffer , Mark A. Scheel

Recent studies invoke a unified description of different neutron star observables using metamodels, which parametrize the Equation of State (EoS) of neutron star matter close to nuclear saturation density in terms of few nuclear parameters.…

High Energy Physics - Phenomenology · Physics 2026-03-26 José Luis Hernández , Cristina Manuel , Laura Tolos

Gravitational waves and electromagnetic signals from merging neutron star binaries provide valuable information about the the properties of dense matter, the formation of heavy elements, and high-energy astrophysics. To fully leverage…

High Energy Astrophysical Phenomena · Physics 2020-10-23 Francois Foucart , Matthew D. Duez , Francois Hebert , Lawrence E. Kidder , Harald P. Pfeiffer , Mark A. Scheel

We study the bulk viscosity of moderately hot and dense, neutrino-transparent color superconducting quark matter arising from weak-interaction-driven direct URCA processes. The quark matter is modeled using the Nambu--Jona-Lasinio model…

Nuclear Theory · Physics 2024-09-16 Mark Alford , Arus Harutyunyan , Armen Sedrakian , Stefanos Tsiopelas

Neutrino transport and neutrino-matter interactions are known to play an important role in the evolution of neutron star mergers, and of their post-merger remnants. Neutrinos cool remnants, drive post-merger winds, and deposit energy in the…

High Energy Astrophysical Phenomena · Physics 2021-11-18 Francois Foucart , Matthew D. Duez , Francois Hebert , Lawrence E. Kidder , Phillip Kovarik , Harald P. Pfeiffer , Mark A. Scheel

Neutrino-matter interactions play a key role in binary neutron star mergers. Thermodynamics conditions at the surfaces where neutrinos decouple from matter influence neutrino spectra, ultimately affecting the evolution of the remnant and…

The stability of the $\beta$-equilibrated dense nuclear matter is analyzed with respect to the thermodynamic stability conditions. Based on the density dependent M3Y effective nucleon-nucleon interaction, the effects of the nuclear…

Nuclear Theory · Physics 2014-09-05 Debasis Atta , D. N. Basu

Numerical simulations of neutron star--neutron star and neutron star--black hole binaries play an important role in our ability to model gravitational wave and electromagnetic signals powered by these systems. These simulations have to take…

High Energy Astrophysical Phenomena · Physics 2023-03-17 Francois Foucart

Mergers of neutron stars (NS+NS) or neutron stars and stellar mass black holes (NS+BS) eject a small fraction of matter with a sub-relativistic velocity. Upon rapid decompression nuclear density medium condenses into neutron rich nuclei,…

Astrophysics · Physics 2009-10-30 Li-Xin Li , Bohdan Paczyński

The dissipative properties of relativistic strongly interacting nuclear matter significantly influence the damping of stellar oscillations and density fluctuations during compact star mergers. In this work, we derive the evolution equation…

High Energy Physics - Phenomenology · Physics 2026-02-18 José Luis Hernandez , Cristina Manuel , Saga Säppi , Laura Tolos

We study bulk viscosity arising from weak current Urca processes in dense baryonic matter at and beyond nuclear saturation density. We consider the temperature regime where neutrinos are trapped and therefore have nonzero chemical…

High Energy Astrophysical Phenomena · Physics 2019-11-27 Mark Alford , Arus Harutyunyan , Armen Sedrakian

We study the shear and bulk viscosity coefficients as well as the thermal conductivity as arising from the collisions among phonons in superfluid neutron stars. We use effective field theory techniques to extract the allowed phonon…

Solar and Stellar Astrophysics · Physics 2014-12-01 Laura Tolos , Cristina Manuel , Sreemoyee Sarkar , Jaume Tarrus

We show that the commonly used criterion for beta equilibrium in neutrino-transparent dense nuclear matter becomes invalid as temperatures rise above 1 MeV. Such temperatures are attained in neutron star mergers. By numerically computing…

Nuclear Theory · Physics 2019-01-02 Mark G. Alford , Steven P. Harris