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Related papers: Stability of rotating spherical stellar systems

200 papers

We study secular stability against a quasi-radial oscillation for rigidly rotating stars with soft equations of state in general relativity. The polytropic equations of state with polytropic index $n$ between 3 and 3.05 are adopted for…

Astrophysics · Physics 2009-11-10 Masaru Shibata

We describe a one-parameter family of models of stable spherical stellar systems in which the phase-space distribution function depends only on energy. The models have similar density profiles in their outer parts ($\rho\propto r^{-4}$) and…

Early-type galaxies -- slow and fast rotating ellipticals (E-SRs and E-FRs) and S0s/lenticulars -- define a Fundamental Plane (FP) in the space of half-light radius $R_e$, enclosed surface brightness $I_e$ and velocity dispersion…

Astrophysics of Galaxies · Physics 2020-05-13 M. Bernardi , H. Domínguez Sanchez , B. Margalef-Bentabol , F. Nikakhtar , R. K. Sheth

Newly born neutron stars can present differential rotation, even if later it should be suppressed by viscosity or a sufficiently strong magnetic field. And in this early stage of its life, a neutron star is expected to have a strong…

General Relativity and Quantum Cosmology · Physics 2013-02-22 Cecilia Chirenti , Jozef Skakala , Shin'ichirou Yoshida

Context. We have investigated the structure and kinematics of triaxial final models formed due to radial-orbit instability from a set of equilibrium anisotropic spherical systems of the Osipkov-Merritt type. Aims. We show that the…

Astrophysics · Physics 2008-11-18 Piffl T. , Sotnikova N. Ya

We describe the astrophysical and numerical basis of N-body simulations, both of collisional stellar systems (dense star clusters and galactic centres) and collisionless stellar dynamics (galaxies and large-scale structure). We explain and…

Instrumentation and Methods for Astrophysics · Physics 2011-05-26 Walter Dehnen , Justin Read

We show that the stellar surface-brightness profiles in disc galaxies---observed to be approximately exponential---can be explained if radial migration efficiently scrambles the individual stars' angular momenta while conserving the…

Astrophysics of Galaxies · Physics 2017-06-13 Jakob Herpich , Scott Tremaine , Hans-Walter Rix

We present the results of a novel type of numerical simulation that realizes a rotating Universe with a shear-free, rigid body rotation inspired by a G\"{o}del-like metric. We run cosmological simulations of unperturbed glasses with various…

Cosmology and Nongalactic Astrophysics · Physics 2024-12-03 Balázs Pál , Tze Goh , Gábor Rácz , István Szapudi

We study the effects of rotation on the torsional modes of oscillating relativistic stars with a solid crust. Earlier works in Newtonian theory provided estimates of the rotational corrections for the torsional modes and suggested that they…

General Relativity and Quantum Cosmology · Physics 2008-11-26 M. Vavoulidis , A. Stavridis , K. D. Kokkotas , H. Beyer

The present paper is devoted to a study of the equilibrium configurations of slowly rotating anisotropic stars in the framework of general relativity. For that purpose, we provide the equations of structure where the rotation is treated to…

General Relativity and Quantum Cosmology · Physics 2024-07-23 Philip Beltracchi , Camilo Posada

Stability is one of the most fundamental aspects regarding planetary systems. It plays an important role in our understanding on the formation channel of the planetary systems, as well as their habitability. Many approaches have been…

Earth and Planetary Astrophysics · Physics 2024-07-22 Hareesh Gautham Bhaskar , Nathaniel W. H. Moore , Jiapeng Gao , Gongjie Li , Billy Quarles

Rotation has a number of important effects on the evolution of stars. Apart from structural changes because of the centrifugal force, turbulent mixing and meridional circulation caused by rotation can dramatically affect a star's chemical…

Solar and Stellar Astrophysics · Physics 2015-06-04 Adrian T. Potter , Christopher A. Tout , Ines Brott

We analyze orbits of stars and dark matter out to three effective radii for 42 galaxies formed in cosmological zoom simulations. Box orbits always dominate at the centers and $z$-tubes become important at larger radii. We connect the…

Astrophysics of Galaxies · Physics 2015-01-06 Bernhard Röttgers , Thorsten Naab , Ludwig Oser

In this paper, we study the dynamics of a system of $n$ coupled, self-propelled particles: $\ddot r_k = (\alpha-\beta |\dot r_k|^2)\dot r_k - \frac{\gamma}{n}\sum_{m=1}^n(r_k-r_m)$, $r_k\in \mathbb R^2.$ Numerical experiments indicate that,…

Dynamical Systems · Mathematics 2025-11-17 Carl Kolon , Constantine Medynets , Irina Popovici

We analyse maps of the spatially-resolved nebular emission of $\approx$1500 star-forming galaxies at $z\approx0.6$-$2.2$ from deep KMOS and MUSE observations to measure the average shape of their rotation curves. We use these to test claims…

We have studied the dynamical evolution of rotating globular clusters with direct $N$-body models. Our initial models are rotating King models; we obtained results for both equal-mass systems and systems composed out of two mass components.…

Astrophysics · Physics 2009-10-07 Andreas Ernst , Patrick Glaschke , Jose Fiestas , Andreas Just , Rainer Spurzem

Large dips in the brightness for a number of stars have been observed, for which the tentative explanation is occultation of the star by a transiting circumplanetary disk or ring system. In order for the circumplanetary disk/rings to block…

Earth and Planetary Astrophysics · Physics 2020-09-11 Jessica Speedie , J. J. Zanazzi

We present N-body/SPH simulations of the evolution of an isolated dwarf galaxy including a detailed model for the ISM, star formation and stellar feedback. Depending on the strength of the feedback, the modelled dwarf galaxy shows periodic…

Astrophysics · Physics 2009-11-10 F. I. Pelupessy , P. P. van der Werf , V. Icke

Many exoplanets are discovered in binary star systems in internal or in circumbinary orbits. Whether the planet can be habitable or not depends on the possibility to maintain liquid water on its surface, and therefore on the luminosity of…

Earth and Planetary Astrophysics · Physics 2021-06-23 G. De Cesare , R. Capuzzo-Dolcetta

An overview of selected topical problems on modelling oscillation properties in solar-like stars is presented. High-quality oscillation data from both space-borne intensity observations and ground-based spectroscopic measurements provide…

Solar and Stellar Astrophysics · Physics 2011-03-28 Gunter Houdek