Galaxy clusters in presence of dark energy: a kinetic approach

Abstract

Context. The external regions of galaxy clusters may be under strong influence of the dark energy, discovered by observations of the SN Ia at redshift z < 1. Aims. The presence of the dark energy in the gravitational equilibrium equation, with the Einstein $\Lambda$ term, contrasts the gravity, making the equilibrium configuration more extended in radius. Methods. In this paper we derive and solve the kinetic equation for an equilibrium configuration in presence of the dark energy, by considering the Newtonian regime, being the observed velocities of the galaxies inside a cluster largely smaller than the light velocity. Results. The presence of the dark energy in the gravitational equilibrium equation leads to wide regions in the $W_0-{\rho }_{\Lambda }$ diagram where the equilibrium solutions are not permitted, due to the prevalence of the effects of the dark energy on the gravity.

arXiv comment10 pages; 6 figures article submitted to Astronomy and Astrophysics

References in corpus (10)

• Observational Evidence from Supernovae for an Accelerating Universe and a Cosmological Constant
• Measurements of Omega and Lambda from 42 High-Redshift Supernovae
• First Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Determination of Cosmological Parameters
• Cosmological parameters from SDSS and WMAP
• Dark energy and the structure of the Coma cluster of galaxies
• Astrophysical Configurations with Background Cosmology: Probing Dark Energy at Astrophysical Scales
• Dark energy and key physical parameters of clusters of galaxies
• Ellipsoidal configurations in the de Sitter spacetime
• Selfgravitating Gas Spheres in a Box and Relativistic Clusters: Relation between Dynamical and Thermodynamical Stability
• Galactic cluster winds in presence of a dark energy

Cited by in corpus (5)

• Constraining phantom braneworld model from cosmic structure sizes
• Does the Corona Borealis Supercluster form a giant binary-like system?
• Orbital precession and other properties of two-body motion in the presence of dark energy
• Two body problem in presence of cosmological constant
• The effects of a non-zero cosmological constant on the Veltmann models