English
Related papers

Related papers: Hyperon bulk viscosity in strong magnetic fields

200 papers

We study the effects of strong magnetic fields on the properties of hyperonic matter. We employ the relativistic mean field theory, which is known to provide excellent descriptions of nuclear matter and finite nuclei. The two additional…

Nuclear Theory · Physics 2009-03-04 P. Yue , F. Yang , H. Shen

The hydrodynamics, describing dynamical effects in superfluid neutron stars, essentially differs from the standard one-fluid hydrodynamics. In particular, we have four bulk viscosity coefficients in the theory instead of one. In this paper…

Astrophysics · Physics 2008-12-18 M. E. Gusakov

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 perform a systematic study of the dependence of the r-mode phenomenology in normal fluid pulsar neutron stars on the symmetry energy slope parameter $L$. An essential ingredient in this study is the bulk viscosity, which is evaluated…

Nuclear Theory · Physics 2020-06-30 T. R. Routray , S. P. Pattnaik , C. Gonzalez-Boquera , X. Viñas , M. Centelles , B. Behera

We use the field theoretical model to perform relativistic calculations of neutrino energy losses caused by the direct Urca processes on nucleons in the degenerate baryon matter. By our analysis, the direct neutron decay in the superdense…

High Energy Physics - Phenomenology · Physics 2009-11-07 L. B. Leinson

In this contribution we study the effects of strong magnetic fields on the particle population of neutron stars with hyperon degrees of freedom in their composition. The star matter is described by a multi-component model with parameterized…

Solar and Stellar Astrophysics · Physics 2014-09-04 R. O. Gomes , V. Dexheimer , C. A. Z. Vasconcellos

We examine bulk viscosity, taking into account trapped neutrinos in baryonic matter, in the context of binary neutron star mergers. Following the merging event, the binary star can yield a remnant compact object with densities up to $5$…

Nuclear Theory · Physics 2024-09-25 Sreemoyee Sarkar , Rana Nandi

Based on the Kaplan-Nelson Lagrangian, we investigate kaon condensation in dense neutron star matter allowing for the explicit presence of hyperons. Using various models we find that the condensate threshold is sensitive to the behavior of…

Nuclear Theory · Physics 2016-09-08 Paul J. Ellis , Roland Knorren , Madappa Prakash

Neutron stars are one of the most exotic objects in the universe and a unique laboratory to study the nuclear matter above the nuclear saturation density. In this work, we study the equation of state of the nuclear matter within a…

Nuclear Theory · Physics 2012-09-26 L. L. Lopes , D. P. Menezes

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 effect of a strong magnetic field on the proton and neutron spin polarization and magnetic susceptibility of asymmetric nuclear matter within a relativistic mean-field approach. It is shown that magnetic fields $B \sim 10^{16}…

Nuclear Theory · Physics 2015-06-23 A. Rabhi , M. A. Pérez-García , C. Providência , I. Vidaña

In this paper, we discuss the damping of density oscillations in dense nuclear matter in the temperature range relevant to neutron star mergers. This damping is due to bulk viscosity arising from the weak interaction ``Urca'' processes of…

Nuclear Theory · Physics 2020-06-23 Mark Alford , Arus Harutyunyan , Armen Sedrakian

We study the effect of magnetic field on the transport properties like shear and bulk viscosities of hot and dense hadronic matter within hadron resonance gas model. We estimate the bulk viscosity using low energy theorems for bilocal…

High Energy Physics - Phenomenology · Physics 2015-03-09 Guru Kadam

The likely presence of $\Lambda$ baryons in dense hadronic matter tends to soften the equation of state to an extend that the observed heaviest neutron stars are difficult to explain. We analyze this "hyperon problem" with a…

Nuclear Theory · Physics 2015-08-26 Paulo F. Bedaque , Andrew W. Steiner

We investigate the effects of strong magnetic fields on the properties of hyperon stars. The matter is described by a hadronic model with parametric coupling. The matter is considered to be at zero temperature, charge neutral,…

Nuclear Theory · Physics 2013-07-30 R. O. Gomes , V. Dexheimer , C. A. Z. Vasconcellos

Isospin-equilibrating weak processes, called ``Urca" processes, are of fundamental importance in astrophysical environments like (proto-)neutron stars, neutron star mergers, and supernovae. In these environments, matter can reach high…

Nuclear Theory · Physics 2025-04-18 Pranjal Tambe , Debarati Chatterjee , Mark Alford , Alexander Haber

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 construct a new equation of state for the baryonic matter under an intense magnetic field within the framework of covariant density functional theory. The composition of matter includes hyperons as well as $ \Delta$-resonances. The…

High Energy Physics - Phenomenology · Physics 2020-11-16 Vivek Baruah Thapa , Monika Sinha , Jia-Jie Li , Armen Sedrakian

Within the covariant density functional theory of hypernuclear matter we build a series of equations of state for hypernuclear compact stars, by calibrating the coupling constants of the $\Xi$-hyperon to the experimental binding energy of…

High Energy Physics - Phenomenology · Physics 2020-02-25 M. Fortin , A. R. Raduta , S. Avancini , C. Providência

In the mean field approximation, we study the effects of weak magnetism and pseudoscalar interaction in the neutrino energy losses caused by the direct Urca processes on relativistic nucleons in the degenerate baryon matter. Our formula for…

High Energy Physics - Phenomenology · Physics 2009-11-07 L. B. Leinson