Published August 1, 2018 | Version v1
Journal article

Cored DARKexp systems with finite size: numerical results

  • 1. Dipartimento di Fisica G. Occhialini, Università Milano-Bicocca and INFN—Sezione di Milano-Bicocca, Piazza della Scienza 3, 20126 Milano (Italy)

Description

In the DARKexp framework for collisionless isotropic relaxation of self-gravitating matter, the central object is the differential energy distribution n(E), which takes a maximum-entropy form proportional to exp[−β(E − Φ(0))] − 1, Φ(0) being the depth of the potential well and β the standard Lagrange multiplier. Then the first and quite non-trivial problem consists in the determination of an ergodic phase-space distribution which reproduces this n(E). In this work we present a very extensive and accurate numerical solution of such DARKexp problem for systems with cored mass density and finite size. This solution holds throughout the energy interval Φ(0)≤ E≤ 0 and is double-valued for a certain interval of β. The size of the system represents a unique identifier for each member of this solution family and diverges as β approaches a specific value. In this limit, the tail of the mass density ρ(r) dies off as r−4, while at small radii it always starts off linearly in r, that is ρ(r)−ρ(0) r.

Availability note (English)

Available from http://dx.doi.org/10.1088/1475-7516/2018/08/026

Additional details

Publishing Information

Journal Title
Journal of Cosmology and Astroparticle Physics
Journal Volume
2018
Journal Issue
08
Journal Page Range
p. 026
ISSN
1475-7516

INIS

Country of Publication
United Kingdom
Country of Input or Organization
International Atomic Energy Agency (IAEA)
INIS RN
51057418
Subject category
S79: ASTROPHYSICS, COSMOLOGY AND ASTRONOMY;
Descriptors DEI
ENERGY SPECTRA; ENTROPY; GRAVITATION; ISOTROPY; LAGRANGIAN FUNCTION; MASS; MATTER; NUMERICAL SOLUTION; PHASE SPACE; RELAXATION
Descriptors DEC
FUNCTIONS; MATHEMATICAL SOLUTIONS; MATHEMATICAL SPACE; PHYSICAL PROPERTIES; SPACE; SPECTRA; THERMODYNAMIC PROPERTIES