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Related papers: Further stable neutron star models from f(R) gravi…

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We study the Starobinsky or $R^2$ model of $f(R)=R+\alpha R^2$ for neutron stars with the structure equations represented by the coupled differential equations and the \emph{polytropic} type of the matter equation of state. The junction…

General Relativity and Quantum Cosmology · Physics 2017-10-11 Wei-Xiang Feng , Chao-Qiang Geng , W. F. Kao , Ling-Wei Luo

The increasing number and precision of measurements of neutron star masses, radii, and, in the near future, moments of inertia offer the possibility of precisely determining the neutron star equation of state. One way to facilitate the…

High Energy Astrophysical Phenomena · Physics 2016-12-14 Carolyn A. Raithel , Feryal Özel , Dimitrios Psaltis

Nuclear matter and neutron stars are studied in the framework of an extended relativistic mean-field (RMF) model with higher-order derivative and density dependent couplings of nucleons to the meson fields. The derivative couplings lead to…

Nuclear Theory · Physics 2015-05-20 Sofija Antić , Stefan Typel

The so-called hyperon puzzle in the theory of neutron stars is considered in the framework of modified $f(R)$ gravity. We show that for simple hyperon equations of state, it is possible to obtain the maximal neutron star mass which…

General Relativity and Quantum Cosmology · Physics 2015-06-18 Artyom V. Astashenok , Salvatore Capozziello , Sergei D. Odintsov

For the propose of confronting updated pulsar observations with developed neutron star equation of states (EoSs), we employ four unified EoSs for both the core and the crust, namely BCPM, BSk20, BSk21, Shen-TM1, as well as two non-unified…

High Energy Astrophysical Phenomena · Physics 2018-01-23 A. Li , N. B. Zhang , B. Qi , G. F. Burgio

We reexamine the equation of state for the nucleonic and hyperonic inner core of neutron stars that satisfies the 2$M_{\odot}$ observations as well as the recent determinations of stellar radii below 13 km, while fulfilling the saturation…

High Energy Astrophysical Phenomena · Physics 2017-12-08 Laura Tolos , Mario Centelles , Angels Ramos

A new scheme for testing nuclear matter equations of state (EsoS) at high densities using constraints from neutron star phenomenology and a flow data analysis of heavy-ion collisions is suggested. An acceptable EoS shall not allow the…

Probably No! As an example, using soft EOSs consistent with existing terrestrial nuclear laboratory experiments for hybrid neutron stars containing a quark core described with MIT bag model using reasonable parameters, we show that the…

Solar and Stellar Astrophysics · Physics 2011-01-11 De-Hua Wen , Bao-An Li , Lie-Wen Chen

We investigate the equilibrium and radial stability of spherically symmetric relativistic stars, considering a polytropic equation of state (EoS), within the framework of $f(R,T)$ gravity with a conservative energy-momentum tensor. Both…

General Relativity and Quantum Cosmology · Physics 2021-08-26 Juan M. Z. Pretel , Sergio E. Jorás , Ribamar R. R. Reis , José D. V. Arbañil

We obtain a new equation of state for the nucleonic and hyperonic inner core of neutron stars that fulfills the 2$M_{\odot}$ observations as well as the recent determinations of stellar radii below 13 km. The nucleonic equation of state is…

High Energy Astrophysical Phenomena · Physics 2016-12-28 Laura Tolos , Mario Centelles , Angels Ramos

The existence of neutron stars with $2M_\odot$ requires the strong stiffness of the equation of state (EoS) of neutron-star matter. We introduce a multi-pomeron exchange potential (MPP) working universally among 3- and 4-baryons to stiffen…

Nuclear Theory · Physics 2017-12-27 Y. Yamamoto , H. Togashi , T. Tamagawa , T. Furumoto , N. Yasutake , Th. A. Rijken

We investigate a conservative formulation of $f(R,T)$ gravity motivated by a key limitation of several existing approaches: the gravitational function is often reconstructed from a chosen equation of state, making the gravity sector…

General Relativity and Quantum Cosmology · Physics 2026-05-12 Ronaldo V. Lobato , Geanderson A. Carvalho , Carlos E. C. Montaña , Jose F. Rodriguez-Ruiz

In the context of f(R) gravity theories, we show that the apparent mass of a neutron star as seen from an observer at infinity is numerically calculable but requires careful matching, first at the star's edge, between interior and exterior…

General Relativity and Quantum Cosmology · Physics 2016-09-14 Miguel Aparicio Resco , Alvaro de la Cruz-Dombriz , Felipe J. Llanes-Estrada , Victor Zapatero Castrillo

We construct equilibrium configurations of uniformly rotating neutron stars for selected relativistic mean-field nuclear matter equations of state (EOS). We compute in particular the gravitational mass ($M$), equatorial ($R_{\rm eq}$) and…

Solar and Stellar Astrophysics · Physics 2015-08-06 Federico Cipolletta , Christian Cherubini , Simonetta Filippi , Jorge A. Rueda , Remo Ruffini

Simultaneous measurement of mass and radius with high precision is essential to unravel the equation of state of matter at the centre of neutron stars. Measurement of massive pulsars indicates that the equation of state has to be stiff at…

Solar and Stellar Astrophysics · Physics 2024-07-19 Asim Kumar Saha , Ritam Mallick

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

The equation of state (EOS) of dense matter has been a long-sought goal of nuclear physics. Equations of state generate unique mass versus radius (M-R) relations for neutron stars, the ultra-dense remnants of stellar evolution. In this…

Nuclear Theory · Physics 2015-06-05 Andrew W. Steiner , James M. Lattimer , Edward F. Brown

We discuss neutron stars with strong magnetic mean fields in the framework of Extended Theories of Gravity. In particular, we take into account models derived from $f(R)$ and $f(\cal G)$ extensions of General Relativity where functions of…

General Relativity and Quantum Cosmology · Physics 2015-06-22 Artyom V. Astashenok , Salvatore Capozziello , Sergei D. Odintsov

Modern multi-messenger astronomical observations and heavy ion experiments provide new insights into the structure of compact objects. Nevertheless, much ambiguity remains when it comes to super dense matter above the nuclear saturation…

General Relativity and Quantum Cosmology · Physics 2021-02-03 Victor I. Danchev , Daniela D. Doneva

Neutron stars with strong magnetic fields are considered in the framework of f(R) gravity. In order to describe dense matter in magnetic field, the model with baryon octet interacting through $\sigma$$\rho$$\omega$-fields is used. The…

General Relativity and Quantum Cosmology · Physics 2015-06-19 Artyom V. Astashenok , Salvatore Capozziello , Sergei D. Odintsov