English
Related papers

Related papers: Bulk viscosity transport coefficients in neutron s…

200 papers

We investigate the weak-interaction-driven bulk-viscous transport properties of $npe$ matter in the neutrino transparent regime. Previous works assumed that the induced bulk viscosity correction to pressure, near beta equilibrium, is linear…

Nuclear Theory · Physics 2023-12-20 Yumu Yang , Mauricio Hippert , Enrico Speranza , Jorge Noronha

In neutron stars, flavor-changing weak interactions determine the equilibrium fraction of protons over neutrons. In binary neutron-star mergers, violent changes in density modify this equilibrium value at timescales of milliseconds,…

Nuclear Theory · Physics 2024-02-13 Yumu Yang , Mauricio Hippert , Enrico Speranza , Jorge Noronha

After an introduction to the QCD phase diagram, the nuclear equations of state, and neutron star mergers, I discuss three projects related to transport and nuclear matter in neutron star mergers. The first is the nature of beta equilibrium…

Nuclear Theory · Physics 2021-11-24 Steven P. Harris

In nuclear matter in isolated neutron stars, the flavor content (e.g., proton fraction) is subject to weak interactions, establishing flavor ($\beta$-)equilibrium. However, there can be deviations from this equilibrium during the merger of…

High Energy Astrophysical Phenomena · Physics 2024-09-04 Elias R. Most , Alexander Haber , Steven P. Harris , Ziyuan Zhang , Mark G. Alford , Jorge Noronha

We present a numerical study of shear viscosity and thermal conductivity of symmetric nuclear matter, pure neutron matter and $\beta$-stable nuclear matter, in the framework of the Brueckner theory. The calculation of in-medium cross…

Solar and Stellar Astrophysics · Physics 2014-11-21 H. F. Zhang , U. Lombardo , W. Zuo

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

We clarify how the weak-interaction-driven bulk viscosity $\zeta$ and the bulk relaxation time $\tau_\Pi$ of neutrino-transparent $npe$ matter depend on the nuclear symmetry energy. We show that, at saturation density, the equation-of-state…

Nuclear Theory · Physics 2025-11-11 Yumu Yang , Mauricio Hippert , Enrico Speranza , Jorge Noronha

The transport property of cold and dense nucleon matter is important for nuclear physics but is relatively less studied than that at finite temperatures. In this paper, we present a primary study of bulk and shear viscosities in the limit…

Nuclear Theory · Physics 2025-04-09 Jianing Li , Weiyao Ke

We calculate the coefficient of bulk viscosity by considering the non-leptonic weak interactions in the cores of hybrid stars with both hyperons and quarks. We first determine the dependence of the production rate of neutrons on the…

Astrophysics · Physics 2009-11-11 Nana Pan , Xiaoping Zheng , Jiarong Li

In this work, we have calculated the transport coefficients: shear viscosity and thermal conductivity inside the neutron star core. Our calculation is based on the relativistic kinetic theory approach using a modified BUU equation for…

Nuclear Theory · Physics 2026-03-20 Utsab Gangopadhyaya , Suman Pal , Gargi Chaudhuri

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 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

Hydrodynamic simulations of neutron star mergers rely on the clear separation between the strong-interaction, weak-interaction, and hydrodynamic timescales. In this effective framework, weak Urca interactions are typically the slowest…

High Energy Astrophysical Phenomena · Physics 2026-03-17 Jamie M. Karthein , Maneesha Sushama Pradeep , Rachel Steinhorst

In order to evaluate qualitatively the space-time evolution of hot and dense nuclear matter the underlying equation of state and transport coefficients must be known. In this study a specific equation of state is studied: the pion gas. The…

Nuclear Theory · Physics 2008-11-26 Azwinndini Muronga

We calculate thermal conductivity and shear viscosity of nucleons in dense nuclear matter of neutron star cores in the non-relativistic Brueckner-Hartree-Fock framework. Nucleon-nucleon interaction is described by the Argonne v18 potential…

Solar and Stellar Astrophysics · Physics 2015-06-17 P. S. Shternin , M. Baldo , P. Haensel

The early post-merger phase of a binary neutron-star coalescence is shaped by characteristic rotational velocities as well as violent density oscillations and offers the possibility to constrain the properties of neutron star matter by…

General Relativity and Quantum Cosmology · Physics 2025-03-10 Michail Chabanov , Luciano Rezzolla

We compute the transport coefficients that appear in the fluid-dynamical equations for the bulk viscous pressure and shear-stress tensor using the 14-moment approximation in the limit of small, but finite, masses. In this limit, we are able…

Nuclear Theory · Physics 2015-06-19 G. S. Denicol , S. Jeon , C. Gale

The transport properties of neutron star matter play an important role in many astrophysical processes. We report the results of a calculation of the shear viscosity and thermal conductivity coefficients of the hard-sphere fermion system of…

Nuclear Theory · Physics 2016-03-23 Angela Mecca , Alessandro Lovato , Omar Benhar , Artur Polls

We review the calculations of the kinetic coefficients (thermal conductivity, shear viscosity, momentum transfer rates) of the neutron star core matter within the framework of the Landau Fermi-liquid theory. We restrict ourselves to the…

Nuclear Theory · Physics 2022-03-23 Peter Shternin , Dmitry Ofengeim

Extraction of bulk nuclear properties by comparing reaction observables to results from semiclassical transport-model simulations is discussed. Specific properties include the nuclear viscosity, incompressibility and constraints on the…

Nuclear Theory · Physics 2007-05-23 P. Danielewicz
‹ Prev 1 2 3 10 Next ›