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Related papers: Rapidly rotating compact stars in Rastall's gravit…

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We present the first calculations of the gravitational radiation produced by nonaxisymmetric dynamical instability in a rapidly rotating compact star. The star deforms into a bar shape, shedding $\sim 4\%$ of its mass and $\sim 17\%$ of its…

General Relativity and Quantum Cosmology · Physics 2009-01-23 J. L. Houser , J. M. Centrella , S. C. Smith

The present paper is devoted to investigate the possible emergence of relativistic compact stellar objects through modified $f(R,T)$ gravity. For anisotropic matter distribution, we used Krori and Barura solutions and two notable and viable…

General Physics · Physics 2018-05-29 Z. Yousaf , M. Zaeem-ul-Haq Bhatti , M. Ilyas

A new non-perturbative method to compute accurate oscillation modes in rapidly rotating stars is presented. In this paper, the effect of the centrifugal force is fully taken into account while the Coriolis force is neglected. This…

Astrophysics · Physics 2009-11-11 F. Lignieres , M. Rieutord , D. Reese

We study by computational means the dynamical stability against bar-mode deformation of rapidly and differentially rotating stars in a post-Newtonian approximation of general relativity. We vary the compaction of the star $M/R$ (where $M$…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Motoyuki Saijo , Masaru Shibata , Thomas W. Baumgarte , Stuart L. Shapiro

We investigate the gravitational models with the non-minimal $Y(R)F^2$ coupled electromagnetic fields to gravity, in order to describe charged compact stars, where $Y(R) $ denotes a function of the Ricci curvature scalar $R$ and $F^2$…

General Relativity and Quantum Cosmology · Physics 2018-03-28 Özcan Sert

We study the gravitational collapse of a spherically symmetric anisotropic relativistic star within Einstein theory of gravity making use of one of our recently developed collapsing stellar models [{\it Astrophys. Space Sci.} {\bf361} 99…

General Relativity and Quantum Cosmology · Physics 2022-01-05 Shyam Das , Bikash Chandra Paul , Ranjan Sharma

A new numerical code for computing stationary axisymmetric rapidly rotating stars in general relativity is presented. The formulation is based on a fully constrained-evolution scheme for 3+1 numerical relativity using the Dirac gauge and…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Lap-Ming Lin , Jerome Novak

The kinetic motion of the stars of a galaxy is considered within the framework of a relativistic scalar theory of gravitation. This model, even though unphysical, may represent a good laboratory where to study in a rigorous, mathematical…

Mathematical Physics · Physics 2017-08-23 Simone Calogero

I discuss and consider the status of observational determinations of the rotation velocities of white dwarf stars via asteroseismology and spectroscopy. While these observations have important implications on our understanding of the…

Solar and Stellar Astrophysics · Physics 2014-10-28 Steven D. Kawaler

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

The properties of uniformly rotating white dwarfs are analyzed within the framework of general relativity. Hartle's formalism is applied to construct self-consistently the internal and external solutions to the Einstein equations. The mass,…

Solar and Stellar Astrophysics · Physics 2012-10-29 Kuantay Boshkayev , Jorge Rueda , Remo Ruffini

In this paper, the gravitational field equations for static spherically symmetric perfect fluid models with a polytropic equation of state, $p=k\rho^{1+1/n}$, are recast into two complementary 3-dimensional {\it regular} systems of ordinary…

General Relativity and Quantum Cosmology · Physics 2009-10-31 U. S. Nilsson , C. Uggla

This work is based on stability analysis of spherically symmetric collapsing star surrounding in locally anisotropic environment in $f(R,T)$ gravity, where $R$ is Ricci scalar and $T$ corresponds to the trace of energy momentum tensor.…

General Physics · Physics 2014-11-26 Ifra Noureen , M. Zubair

We propose a new numerical method to calculate irrotational binary systems composed of compressible gaseous stars in Newtonian gravity. Assuming irrotationality, i.e. vanishing of the vorticity vector everywhere in the star in the inertial…

Astrophysics · Physics 2009-10-30 Koji Uryu , Yoshiharu Eriguchi

We will briefly discuss the necessary conditions for stability of polytropies in $f(\hat R)$ Palatini gravity and the differences with the General Relativity ones.

General Relativity and Quantum Cosmology · Physics 2020-01-03 Aneta Wojnar

The present work investigates the numerical evolution of linearized oscillations of non-rotating, spherically symmetric neutron stars within the framework of general relativity. We derive the appropriate equations using the (3+1)-formalism.…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Johannes Ruoff

The measured rotation velocity profiles of mature spiral galaxies are successfully described with a gravitational model consisting of a thin axisymmetric disk of finte radius. The disk is assumed uniformly thin but with variable radial mass…

Astrophysics · Physics 2008-03-06 James Q. Feng , C. F. Gallo

We study models of uniformly and differentially rotating neutron stars in the framework of post-Newtonian approximation in general relativity as established by Chandrasechar. In particular, we adopt the polytropic equation of state in order…

High Energy Astrophysical Phenomena · Physics 2023-05-05 Athanasios Fotopoulos , Vasileios G. Karageorgopoulos , Vassilis S. Geroyannis

We consider a further extension of our previous works in the treatment of the three-dimensional general relativistic Poynting-Robertson effect, which describes the motion of a test particle around a compact object as affected by the…

General Relativity and Quantum Cosmology · Physics 2021-05-12 Vittorio De Falco , Maciek Wielgus

The interest in studying relativistic compact objects play an important role in modern astrophysics with an aim to understand several astrophysical issues. It is therefore natural to ask for internal structure and physical properties of…

General Physics · Physics 2018-09-19 S. K. Maurya , Ayan Banerjee , Y. K. Gupta