Structure Formation by the Fifth Force III: Segregation of Baryons and Dark Matter

Abstract

In this paper we present the results of $N$-body simulations with a scalar field coupled differently to cold dark matter (CDM) and baryons. The scalar field potential and coupling function are chosen such that the scalar field acquires a heavy mass in regions with high CDM density and thus behaves like a chameleon. We focus on how the existence of the scalar field affects the formation of nonlinear large-scale structure, and how the different couplings of the scalar field to baryons and CDM particles lead to different distributions and evolutions for these two matter species, both on large scales and inside virialized halos. As expected, the baryon-CDM segregation increases in regions where the fifth force is strong, and little segregation in dense regions. We also introduce an approximation method to identify the virialized halos in coupled scalar field models which takes into account the scalar field coupling and which is easy to implement numerically. It is find that the chameleon nature of the scalar field makes the internal density profiles of halos dependent on the environment in a very nontrivial way.

22 pages, 11 figures, 1 table. Revised version accepted for publication in Phys. Rev. D. For a high resolution version see http://www.damtp.cam.ac.uk/user/bl267/Li_Zhao/N_body_segregation.pdf

References in corpus (16)

• Dynamics of dark energy
• Models of f(R) Cosmic Acceleration that Evade Solar-System Tests
• Are f(R) dark energy models cosmologically viable ?
• Evading Equivalence Principle Violations, Cosmological and other Experimental Constraints in Scalar Field Theories with a Strong Coupling to Matter
• The Cosmology of f(R) Gravity in the Metric Variational Approach
• f(R) Gravity and Chameleon Theories
• The speed of the `bullet' in the merging galaxy cluster 1E0657-56
• Non-linear evolution of f(R) cosmologies II: power spectrum
• Strongly Coupled Chameleon Fields: New Horizons in Scalar Field Theory
• Non-linear evolution of f(R) cosmologies I: methodology
• Tidal Tails Test the Equivalence Principle in the Dark Sector
• Galilean Equivalence for Galactic Dark Matter
• Accurate estimators of power spectra in N-body simulations
• A New Force in the Dark Sector?
• Galaxy Satellites and the Weak Equivalence Principle
• Structure Formation by Fifth Force: Power Spectrum from N-Body Simulations

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