Impact of kinetic and potential self-interactions on scalar dark matter
| Autor: | Philippe Brax, Patrick Valageas, Jose A. R. Cembranos |
|---|---|
| Přispěvatelé: | Institut de Physique Théorique - UMR CNRS 3681 (IPHT), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS) |
| Jazyk: | angličtina |
| Rok vydání: | 2019 |
| Předmět: |
cosmological model
nonpolynomial 01 natural sciences General Relativity and Quantum Cosmology law.invention Gravitation pressure halo: density law dark matter: scalar Conservation of mass Physics virial theorem interaction: scalar velocity: acoustic Cosmology finite size Quantum electrodynamics symbols [PHYS.GRQC]Physics [physics]/General Relativity and Quantum Cosmology [gr-qc] Vector field dark matter: fuzzy k-essence Scalar field soliton Astrophysics - Cosmology and Nongalactic Astrophysics Cosmology and Nongalactic Astrophysics (astro-ph.CO) Dark matter FOS: Physical sciences General Relativity and Quantum Cosmology (gr-qc) Astrophysics::Cosmology and Extragalactic Astrophysics dark matter: density approximation: fluid nonrelativistic symbols.namesake 0103 physical sciences conservation law 010306 general physics halo: mass perturbation theory 010308 nuclear & particles physics Scalar (physics) Física stability Euler equations field theory: scalar 13. Climate action gravitation density dependence model: scalar galaxy Hydrostatic equilibrium [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] |
| Zdroj: | Phys.Rev.D Phys.Rev.D, 2019, 100 (2), pp.023526. ⟨10.1103/PhysRevD.100.023526⟩ E-Prints Complutense: Archivo Institucional de la UCM Universidad Complutense de Madrid Physical Review D E-Prints Complutense. Archivo Institucional de la UCM instname Physical Review D, American Physical Society, 2019, 100 (2), pp.023526. ⟨10.1103/PhysRevD.100.023526⟩ |
| ISSN: | 1550-7998 1550-2368 |
| DOI: | 10.1103/PhysRevD.100.023526⟩ |
| Popis: | We consider models of scalar dark matter with a generic interaction potential and non-canonical kinetic terms of the K-essence type that are subleading with respect to the canonical term. We analyze the low-energy regime and derive, in the nonrelativistic limit, the effective equations of motions. In the fluid approximation they reduce to the conservation of matter and to the Euler equation for the velocity field. We focus on the case where the scalar field mass $10^{-21} \ll m \lesssim 10^{-4} \, {\rm eV}$ is much larger than for fuzzy dark matter, so that the quantum pressure is negligible on cosmological and galactic scales, while the self-interaction potential and non-canonical kinetic terms generate a significant repulsive pressure. At the level of cosmological perturbations, this provides a dark-matter density-dependent speed of sound. At the nonlinear level, the hydrostatic equilibrium obtained by balancing the gravitational and scalar interactions imply that virialized structures have a solitonic core of finite size depending on the speed of sound of the dark matter fluid. For the most relevant potential in $\lambda_4 \phi^4/4$ or K-essence with a $(\partial \phi)^4$ interaction, the size of such stable cores cannot exceed 60 kpc. Structures with a density contrast larger than $10^6$ can be accommodated with a speed of sound $c_s\lesssim 10^{-6}$. We also consider the case of a cosine self-interaction, as an example of bounded nonpolynomial self-interaction. This gives similar results in low-mass and low-density halos whereas solitonic cores are shown to be absent in massive halos. Comment: 25 pages |
| Databáze: | OpenAIRE |
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