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Related papers: Neutron Stars in Scalar-tensor Gravity with Quarti…

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We investigate the effect of a strong magnetic field on the structure of neutron stars in a model with perturbative $f(R)$ gravity. The effect of an interior strong magnetic field of about $10^{17 \sim 18}$ G on the equation of state is…

High Energy Astrophysical Phenomena · Physics 2015-06-15 Myung-Ki Cheoun , Cemsinan Deliduman , Can Güngör , Vildan Keleş , C. Y. Ryu , Toshitaka Kajino , Grant J. Mathews

In this work we investigate neutron stars (NS) in $f(\mathcal{R,T})$ gravity for the case $R+2\lambda\mathcal{T}$, $\mathcal{R}$ is the Ricci scalar and $\mathcal{T}$ the trace of the energy-momentum tensor. The hydrostatic equilibrium…

High Energy Astrophysical Phenomena · Physics 2021-01-01 R. Lobato , O. Lourenço , P. H. R. S. Moraes , C. H. Lenzi , M. de Avellar , W. de Paula , M. Dutra , M. Malheiro

We consider neutron star configurations in the scalar-tensor theory of gravity with the coupling between the kinetic term of a scalar field and the Einstein tensor (such the model is a subclass of Horndeski gravity). Neutron stars in this…

General Relativity and Quantum Cosmology · Physics 2023-01-18 Pavel E. Kashargin , Sergey V. Sushkov

We analyze numerically the dynamical transition to spontaneous scalarization in neutron stars in the framework of a scalar-tensor theory of gravity where the scalar field is free but massive, and it is coupled nonminimally to gravity in the…

General Relativity and Quantum Cosmology · Physics 2024-10-04 Juan Carlos Degollado , Néstor Ortiz , Marcelo Salgado

The current work investigates the structural properties of neutron stars in the presence of a strong magnetic field within the framework of f(R,T) modified gravity, where the matter-geometry coupling leads to deviations from general…

General Relativity and Quantum Cosmology · Physics 2026-03-24 Charul Rathod , M. Mishra , Prasanta Kumar Das

The properties of neutron stars are determined by the nature of the matter that they contain. These properties can be constrained by measurements of the star's size. We obtain stringent constraints on neutron-star radii by combining…

High Energy Astrophysical Phenomena · Physics 2020-03-25 Collin D. Capano , Ingo Tews , Stephanie M. Brown , Ben Margalit , Soumi De , Sumit Kumar , Duncan A. Brown , Badri Krishnan , Sanjay Reddy

A novel equation of state with the surface tension induced by particles' interactions was generalized to describe the properties of the neutron stars (NSs). In this equation the interaction between particles occurs via the hard core…

High Energy Astrophysical Phenomena · Physics 2017-12-19 Violetta V. Sagun , Ilidio Lopes

Combining the GW observations of merging systems of binary neutron stars and quasi-universal relations, we set constraints on the maximum mass that can be attained by nonrotating stellar models of neutron stars. More specifically,…

High Energy Astrophysical Phenomena · Physics 2018-09-06 Luciano Rezzolla , Elias R. Most , Lukas R. Weih

We study the interaction of massless scalar fields with self-gravitating neutron stars by means of fully dynamic numerical simulations of the Einstein-Klein-Gordon perfect fluid system. Our investigation is restricted to spherical symmetry…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Florian Siebel , Jose A. Font , Philippos Papadopoulos

We investigate the properties of the neutron star with relativistic mean field models. We incorporate in the quantum hadrodynamics and in the quark-meson coupling models a possible reduction of meson masses in nuclear matter. The equation…

Nuclear Theory · Physics 2007-05-23 C. Y. Ryu , C. H. Hyun , S. W. Hong , B. K. Jennings

Neutron star models in perturbative $f(R)$ gravity are considered with realistic equations of state. In particular, we consider the FPS, SLy and other equations of state and a case of piecewise equation of state for stars with quark cores.…

General Relativity and Quantum Cosmology · Physics 2015-06-17 Artyom V. Astashenok , Salvatore Capozziello , Sergei D. Odintsov

Hybrid neutron stars, the compact objects consisting hadronic matter and strange quark matter, can be considered as the probes for the scalar tensor gravity. In this work, we explore the scalarization of hybrid neutron stars in the scalar…

High Energy Astrophysical Phenomena · Physics 2025-10-08 Fahimeh Rahimi , Zeinab Rezaei

The realistic models of neutron stars are considered for simple $R+\alpha R^2$ gravity and equivalent Brance-Dicke theory with dilaton field in Einsein frame. For negative values of $\alpha$ we have no acceptable results from astrophysical…

General Relativity and Quantum Cosmology · Physics 2018-12-27 Artyom V. Astashenok , Alexey S. Baigashov , Sergey A. Lapin

We construct rapidly rotating neutron star models in scalar-tensor theories with a massive scalar field. The fact that the scalar field has nonzero mass leads to very interesting results since the allowed range of values of the coupling…

General Relativity and Quantum Cosmology · Physics 2016-11-15 Daniela D. Doneva , Stoytcho S. Yazadjiev

In this work, we investigate the existence of neutron stars (NS) in the framework of $f$($\mathbb{T}$,$\mathcal{T}$) gravity, where $\mathbb{T}$ is the torsion tensor and $\mathcal{T}$ is the trace of the energy-momentum tensor. The…

High Energy Astrophysical Phenomena · Physics 2023-01-11 Clésio E. Mota , Luis C. N. Santos , Franciele M. da Silva , Cesar V. Flores , Iarley P. Lobo , Valdir B. Bezerra

We construct parameter sets of the relativistic mean-field model fitted to the recent constraints on the asymmetry energy $J$ and the slope parameter $L$ for pure neutron matter. We find cases of unphysical behaviour, i.e.\ the appearance…

High Energy Astrophysical Phenomena · Physics 2018-12-19 Nadine Hornick , Laura Tolos , Andreas Zacchi , Jan-Erik Christian , Jürgen Schaffner-Bielich

We study how light scalar fields can change the stellar landscape by triggering a new phase of nuclear matter. Scalars coupled to nucleons can develop a non-trivial expectation value at finite baryon density. This sourcing of a scalar…

High Energy Physics - Phenomenology · Physics 2023-07-28 Reuven Balkin , Javi Serra , Konstantin Springmann , Stefan Stelzl , Andreas Weiler

An isovector-scalar meson is incorporated self-consistently into the quark-meson coupling description of nuclear matter and its most prominent effects on the structure of neutron stars are investigated. The recent measurement of GW170817 is…

Nuclear Theory · Physics 2019-08-07 T. F. Motta , A. M. Kalaitzis , S. Antić , P. A. M. Guichon , J. R. Stone , A. W. Thomas

We present solutions for non-spherically symmetric neutron stars. We begin by deriving the Tolman-Oppenheimer-Volkoff equations from a parameterized metric that takes into account the deformation of the star due to differences in equatorial…

General Relativity and Quantum Cosmology · Physics 2024-03-01 J. T. Quartuccio , P. H. R. S. Moraes , J. D. V. Arbañil

In this work we study static neutron stars in the context of several inflationary models which are popular in cosmology. These inflationary models are non-minimally coupled scalar theories which yield a viable inflationary phenomenology in…

General Relativity and Quantum Cosmology · Physics 2023-05-31 S. D. Odintsov , V. K. Oikonomou