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Related papers: Newtonian and relativistic polytropes

200 papers

The inner structure of neutron stars is still an open question. To make progress and understand the qualitative impact of gauge interactions on the neutron star structure we study neutron stars in a modified version of QCD. In this…

High Energy Astrophysical Phenomena · Physics 2017-10-23 Ouraman Hajizadeh , Axel Maas

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

The confluence of major theoretical, experimental, and observational advances are providing a unique perspective on the equation of state of dense neutron-rich matter -- particularly its symmetry energy -- and its imprint on the mass-radius…

Nuclear Theory · Physics 2023-04-13 Marc Salinas , Jorge Piekarewicz

Phenomenological calculations of the properties of dense matter, such as relativistic mean-field theories, represent a pathway to predicting the microscopic and macroscopic properties of neutron stars. However, such theories do not…

Nuclear Theory · Physics 2025-11-03 Isaac Legred , Liam Brodie , Alexander Haber , Reed Essick , Katerina Chatziioannou

Neutron stars are cosmic laboratories to study dense matter in Quantum Chromodynamics (QCD). The observable mass-radius relations of neutron stars are determined by QCD equations of state, and can reflect the properties of QCD phase…

Nuclear Theory · Physics 2021-05-04 Toru Kojo

We present a class of exact solutions of Einstein's gravitational field equations describing spherically symmetric and static anisotropic stellar type configurations. The solutions are obtained by assuming a particular form of the…

General Relativity and Quantum Cosmology · Physics 2017-10-04 T. Harko , M. K. Mak

In this paper we will discuss charged stars with polytropic equation of state, where we will try to derive an equation analogous to the Lane-Emden equation. We will assume that these stars are spherically symmetric, and the electric field…

Astrophysics · Physics 2009-11-10 Rodrigo Picanco , Manuel Malheiro , Subharthi Ray

We study the properties of neutron stars adopting relativistic equations of state of neutron star matter, calculated in the framework of the relativistic Brueckner-Hartree-Fock approximation for electrically charge neutral neutron star…

Nuclear Theory · Physics 2009-10-30 H. Huber , F. Weber , M. K. Weigel , Ch. Schaab

We investigate theoretical and observational constraints on the mass-radius relations for neutron stars. For that purpose we consider the model of neutron stars taking into considerations strong, weak, electromagnetic and gravitational…

High Energy Astrophysical Phenomena · Physics 2016-06-28 Kuantay Boshkayev , Jorge A. Rueda , Marco Muccino

The equations of state for a characteristic spacetime are studied in the context of the spherically symmetric interior exact and analytical solutions in Horava gravity and Einstein-aether theory in which anisotropic fluids are considered.…

General Relativity and Quantum Cosmology · Physics 2018-08-06 Daniele Vernieri

The gravitational properties of astrophysical objects depend sensitively on their internal structure. In Newtonian theory, the gravitational potential of a rotating star can be fully described by an infinite number of multipole moments of…

General Relativity and Quantum Cosmology · Physics 2014-10-01 Katerina Chatziioannou , Kent Yagi , Nicolas Yunes

One of the key goals of observing neutron stars is to infer the equation of state (EoS) of the cold, ultradense matter in their interiors. We present here a Bayesian statistical method of inferring the pressures at five fixed densities,…

High Energy Astrophysical Phenomena · Physics 2017-08-09 Carolyn A. Raithel , Feryal Özel , Dimitrios Psaltis

A fully self-consistent model of the neutron star inner crust based upon models of the nucleonic equation of state at zero temperature is constructed. The results nearly match those of previous calculations of the inner crust given the same…

Nuclear Theory · Physics 2008-11-26 Andrew W. Steiner

Spherically symmetric relativistic stars with the polytropic equation of state (EoS), which possess the local pressure anisotropy, are considered within the framework of general relativity. The generalized Lane-Emden equations are derived…

General Relativity and Quantum Cosmology · Physics 2018-01-12 A. A. Isayev

Neutron star observations, including direct mass and radius measurements as well as the analysis of gravitational wave signals emitted by stellar mergers, provide valuable and unique insights into the properties of strongly interacting…

Nuclear Theory · Physics 2019-02-20 Aleksi Vuorinen

A central open problem in nuclear physics is the determination of a physically robust equation of state (EoS) for dense nuclear matter, which directly informs our understanding of the internal composition and macroscopic properties of…

Nuclear Theory · Physics 2025-12-08 I. Stergakis , Th. Diakonidis , Ch. C. Moustakidis

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

We contribute a publicly available set of tables and code to provide Equations of State (EoS) for matter at neutron star densities. Our EoSes are constrained only by input from hadron physics and fundamental principles, without feedback…

General Relativity and Quantum Cosmology · Physics 2021-03-24 Eva Lope Oter , Andreas Windisch , Felipe J. Llanes-Estrada , Mark Alford

Microscopic calculations of neutron matter based on nuclear interactions derived from chiral effective field theory, combined with the recent observation of a 1.97 +- 0.04 M_sun neutron star, constrain the equation of state of neutron-rich…

Solar and Stellar Astrophysics · Physics 2013-07-23 K. Hebeler , J. M. Lattimer , C. J. Pethick , A. Schwenk

Recent progress in the determination of both masses and radii of neutron stars are starting to place stringent constraints on the dense matter equation of state. In particular, new theoretical developments together with improved statistical…

Nuclear Theory · Physics 2015-10-21 Wei-Chia Chen , J. Piekarewicz