Self-similar Expansion of Axisymmetric Voids

Abstract

view Abstract Citations (7) References (18) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Self-similar Expansion of Axisymmetric Voids Ryden, Barbara S. Abstract Self-similar solutions are found for the collisionless expansion of axisymmetric density deficits (voids) in an Einstein-de Sitter universe. At large radii, the isodensity contours of the model voids are assumed to be either oblate spheroids, with axis ratio 3:5, or prolate spheroids, with axis ratio 5:3. The asymptotic density profile has the form δ ∝ -r-ν. I investigate voids with ν = 1 to ν = 2.5. Both oblate and prolate voids with ν > 2 form nearly spherical dense shells surrounding the central void. Models with ν = 2 form partial shells, taking the form of polar caps for an oblate void and an equatorial belt for a prolate void. Models with ν <2 which are oblate at large radii have isodensity contours which are approximately spherical at intermediate radii and even become prolate in the central regions, where δ ≲ -0.9. Similarly, models with ν > 2 which are prolate at large radii become oblate in the central regions. In all the models examined, the peculiar velocity of each particle is smaller than its Hubble velocity relative to the void center. Publication: The Astrophysical Journal Pub Date: March 1994 DOI: 10.1086/173832 Bibcode: 1994ApJ...423..534R Keywords: COSMOLOGY: THEORY; GALAXIES: CLUSTERING full text sources ADS |