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Related papers: I-Q relation for rapidly rotating neutron stars

200 papers

We are investigating universal relations between different normalisations of the moment of inertia and the compactness of neutron and strange stars. Slowly rotating as well as rapidly rotating models are studied in General Relativity,…

General Relativity and Quantum Cosmology · Physics 2016-04-13 Kalin V. Staykov , Daniela D. Doneva , Stoytcho S. Yazadjiev

We investigate the quantum hadrodynamic equation of state for neutron stars (with and without including hyperons) in the presence of strong magnetic fields. The deduced masses and radii are consistent with recent observations of high mass…

High Energy Astrophysical Phenomena · Physics 2012-11-19 Chung-Yeol Ryu , Myung-Ki Cheoun , Toshitaka Kajino , Tomoyuki Maruyama , Grant J. Mathews

Existing estimates of the gravitational-wave damping timescale of the dominant quadrupole oscillation mode in the case of rapidly rotating stars are based on using a Newtonian estimate for the energy of the mode, in combination with the…

General Relativity and Quantum Cosmology · Physics 2018-01-10 Georgios Lioutas , Nikolaos Stergioulas

In this short note, we investigate the existence of universal relations between the gravimagnetic Love number of irrotational stars and the dimensionless moment of inertia. These Love numbers take into account the internal motion of the…

General Relativity and Quantum Cosmology · Physics 2015-04-29 Térence Delsate

We assess the universal relations among second-order moments of relativistic stars, namely the moment of inertia, tidal deformability, and spin-induced quadrupole moment, via reformulated perturbation equations. After constructing the…

General Relativity and Quantum Cosmology · Physics 2025-07-29 Koutarou Kyutoku

A set of theoretical mass-radius relations for rigidly rotating neutron stars with exotic cores, obtained in various theories of dense matter, is reviewed. Two basic observational constraints are used: the largest measured rotation…

High Energy Astrophysical Phenomena · Physics 2016-04-20 P. Haensel , M. Bejger , M. Fortin , J. L. Zdunik

For neutron stars, there exist universal relations insensitive to the equation of states, the so called I-Love-Q relations, which show the connections among the moment of inertia, tidal Love number and quadrupole moment. In this paper, we…

High Energy Astrophysical Phenomena · Physics 2025-02-05 Jing-Yi Wu , Wei Li , Xin-Han Huang , Kilar Zhang

As some of the most compact stellar objects in the universe, neutron stars are unique cosmic laboratories. The study of neutron stars provides an ideal theoretical testbed for investigating both physics at supra-nuclear densities as well as…

High Energy Astrophysical Phenomena · Physics 2023-05-29 Grigorios Papigkiotis , George Pappas

In the modern era of abundant X-ray detections and the increasing momentum of gravitational waves astronomy, tests of General Relativity in strong field regime become increasingly feasible and their importance for probing gravity cannot be…

General Relativity and Quantum Cosmology · Physics 2020-09-25 Victor I. Danchev , Daniela D. Doneva , Stoytcho S. Yazadjiev

In recent years there has been a surge of interest in what has come to be known as the `universal relations' between various global properties of neutron stars. These universal relations are equation of state independent relations between…

General Relativity and Quantum Cosmology · Physics 2019-05-13 George Pappas , Daniela D. Doneva , Thomas P. Sotiriou , Stoytcho S. Yazadjiev , Kostas D. Kokkotas

First proposed in 2013 by Yagi and Yunes, the quasi-universal \emph{I-Love-Q relations} consist of a set of relations between the moment of inertia, the spin-induced quadrupole moment and the electric quadrupolar tidal deformability of…

High Energy Physics - Theory · Physics 2021-01-27 Christoph Adam , Alberto García Martín-Caro , Miguel Huidobro , Ricardo Vázquez , Andrzej Wereszczynski

Certain bulk properties of neutron stars, in particular their moment of inertia, rotational quadrupole moment and tidal Love number, when properly normalized, are related to one another in a nearly equation of state independent way. The…

General Relativity and Quantum Cosmology · Physics 2017-12-20 Hector O. Silva , Nicolas Yunes

In this work, we study the influence of $f(R,T)$ gravity on rapidly rotating neutron stars. First we discuss the main aspects of this modified theory of gravity where the gravitational Lagrangian is an arbitrary function of the Ricci scalar…

General Relativity and Quantum Cosmology · Physics 2023-05-03 F. M. da Silva , L. C. N. Santos , C. E. Mota , T. O. F. da Costa , J. C. Fabris

In this work, we study the impact of anisotropy on slowly rotating neutron stars by extending the Hartle-Thorne formalism in general relativity to include anisotropy in pressure up to second order in the angular velocity. We assess the…

General Relativity and Quantum Cosmology · Physics 2024-10-10 L. M. Becerra , E. A. Becerra-Vergara , F. D. Lora-Clavijo

We have developed a numerical code to study the deformation ($\varepsilon = (I_{zz}-I_{xx})/I_{zz}$, where $I_{ii}$ are the moments of inertia) of neutron stars in rapidly rotation in a fully general relativistic calculation. We have found…

Astrophysics · Physics 2007-05-23 J. C. N. de Araujo , J. A. de Freitas Pacheco , M. Cattani , J. E. Horvath

We consider rapidly rotating black holes and neutron stars in dilatonic Einstein-Gauss-Bonnet (EGBd) theory and determine their quadrupole moments, which receive a contribution from the dilaton. The quadrupole moment of EGBd black holes can…

General Relativity and Quantum Cosmology · Physics 2014-09-08 Burkhard Kleihaus , Jutta Kunz , Sindy Mojica

Neutron stars are highly compact astrophysical objects and therefore of utmost relevance to learn about theories of gravity. Whereas the proper equation of state of the nuclear matter inside neutron stars is not yet known, and a wide range…

General Relativity and Quantum Cosmology · Physics 2022-04-28 Jutta Kunz

No-hair like relations between the multipole moments of the exterior gravitational field of neutron stars have recently been found to be approximately independent of the star's internal structure. This approximate, equation-of-state…

General Relativity and Quantum Cosmology · Physics 2015-08-06 Barun Majumder , Kent Yagi , Nicolas Yunes

Certain relations among neutron-star observables that are insensitive to the equation of state are known to exist. Such universal relations have been shown to be valid for cold and stationary neutron stars. Here, we study these relations in…

High Energy Astrophysical Phenomena · Physics 2024-02-19 Victor Guedes , Shu Yan Lau , Cecilia Chirenti , Kent Yagi

Using the nuclear equation of states for a large variety of relativistic and non-relativistic force parameters, we calculate the static and rotating masses and radii of neutron stars. From these equation of states, we also evaluate the…

Solar and Stellar Astrophysics · Physics 2013-12-23 Shailesh K. Singh , S. K. Biswal , M. Bhuyan , T. K. Jha , S. K. Patra