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Title: Interacting warm dark matter

Abstract

We explore a cosmological model composed by a dark matter fluid interacting with a dark energy fluid. The interaction term has the non-linear λρ{sub m}{sup α}ρ{sub e}{sup β} form, where ρ{sub m} and ρ{sub e} are the energy densities of the dark matter and dark energy, respectively. The parameters α and β are in principle not constrained to take any particular values, and were estimated from observations. We perform an analytical study of the evolution equations, finding the fixed points and their stability properties in order to characterize suitable physical regions in the phase space of the dark matter and dark energy densities. The constants (λ,α,β) as well as w{sub m} and w{sub e} of the EoS of dark matter and dark energy respectively, were estimated using the cosmological observations of the type Ia supernovae and the Hubble expansion rate H(z) data sets. We find that the best estimated values for the free parameters of the model correspond to a warm dark matter interacting with a phantom dark energy component, with a well goodness-of-fit to data. However, using the Bayesian Information Criterion (BIC) we find that this model is overcame by a warm dark matter – phantom dark energy modelmore » without interaction, as well as by the ΛCDM model. We find also a large dispersion on the best estimated values of the (λ,α,β) parameters, so even if we are not able to set strong constraints on their values, given the goodness-of-fit to data of the model, we find that a large variety of theirs values are well compatible with the observational data used.« less

Authors:
; ;  [1];  [2]
  1. Departamento de Física, Facultad de Ciencia, Universidad de Santiago de Chile, Casilla 307, Santiago (Chile)
  2. Departamento de Física, DCI, Campus León, Universidad de Guanajuato, CP. 37150, León, Guanajuato (Mexico)
Publication Date:
OSTI Identifier:
22282887
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2013; Journal Issue: 05; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; COSMOLOGICAL CONSTANT; COSMOLOGICAL MODELS; DENSITY; ENERGY DENSITY; EVOLUTION; EXPANSION; LIMITING VALUES; NONLINEAR PROBLEMS; NONLUMINOUS MATTER; PHASE SPACE; SUPERNOVAE

Citation Formats

Cruz, Norman, Palma, Guillermo, Zambrano, David, and Avelino, Arturo, E-mail: norman.cruz@usach.cl, E-mail: guillermo.palma@usach.cl, E-mail: david.zambrano@gmail.com, E-mail: avelino@fisica.ugto.mx. Interacting warm dark matter. United States: N. p., 2013. Web. doi:10.1088/1475-7516/2013/05/034.
Cruz, Norman, Palma, Guillermo, Zambrano, David, & Avelino, Arturo, E-mail: norman.cruz@usach.cl, E-mail: guillermo.palma@usach.cl, E-mail: david.zambrano@gmail.com, E-mail: avelino@fisica.ugto.mx. Interacting warm dark matter. United States. doi:10.1088/1475-7516/2013/05/034.
Cruz, Norman, Palma, Guillermo, Zambrano, David, and Avelino, Arturo, E-mail: norman.cruz@usach.cl, E-mail: guillermo.palma@usach.cl, E-mail: david.zambrano@gmail.com, E-mail: avelino@fisica.ugto.mx. 2013. "Interacting warm dark matter". United States. doi:10.1088/1475-7516/2013/05/034.
@article{osti_22282887,
title = {Interacting warm dark matter},
author = {Cruz, Norman and Palma, Guillermo and Zambrano, David and Avelino, Arturo, E-mail: norman.cruz@usach.cl, E-mail: guillermo.palma@usach.cl, E-mail: david.zambrano@gmail.com, E-mail: avelino@fisica.ugto.mx},
abstractNote = {We explore a cosmological model composed by a dark matter fluid interacting with a dark energy fluid. The interaction term has the non-linear λρ{sub m}{sup α}ρ{sub e}{sup β} form, where ρ{sub m} and ρ{sub e} are the energy densities of the dark matter and dark energy, respectively. The parameters α and β are in principle not constrained to take any particular values, and were estimated from observations. We perform an analytical study of the evolution equations, finding the fixed points and their stability properties in order to characterize suitable physical regions in the phase space of the dark matter and dark energy densities. The constants (λ,α,β) as well as w{sub m} and w{sub e} of the EoS of dark matter and dark energy respectively, were estimated using the cosmological observations of the type Ia supernovae and the Hubble expansion rate H(z) data sets. We find that the best estimated values for the free parameters of the model correspond to a warm dark matter interacting with a phantom dark energy component, with a well goodness-of-fit to data. However, using the Bayesian Information Criterion (BIC) we find that this model is overcame by a warm dark matter – phantom dark energy model without interaction, as well as by the ΛCDM model. We find also a large dispersion on the best estimated values of the (λ,α,β) parameters, so even if we are not able to set strong constraints on their values, given the goodness-of-fit to data of the model, we find that a large variety of theirs values are well compatible with the observational data used.},
doi = {10.1088/1475-7516/2013/05/034},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 05,
volume = 2013,
place = {United States},
year = 2013,
month = 5
}
  • It has been shown by many independent studies that the cold dark matter scenario produces singular galactic dark halos, in strong contrast with observations. Possible remedies are that either the dark matter is warm so that it has significant thermal motion or that the dark matter has strong self-interactions. We combine these ideas to calculate the linear mass power spectrum and the spectrum of cosmic microwave background (CMB) fluctuations for self-interacting warm dark matter. Our results indicate that such models have more power on small scales than is the case for the standard warm dark matter model, with a CMBmore » fluctuation spectrum which is nearly indistinguishable from standard cold dark matter. This enhanced small-scale power may provide better agreement with the observations than does standard warm dark matter. (c) 2000 The American Physical Society.« less
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