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 nonlinear 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 goodnessoffit 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 »
 Authors:
 Departamento de Física, Facultad de Ciencia, Universidad de Santiago de Chile, Casilla 307, Santiago (Chile)
 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, Email: norman.cruz@usach.cl, Email: guillermo.palma@usach.cl, Email: david.zambrano@gmail.com, Email: avelino@fisica.ugto.mx. Interacting warm dark matter. United States: N. p., 2013.
Web. doi:10.1088/14757516/2013/05/034.
Cruz, Norman, Palma, Guillermo, Zambrano, David, & Avelino, Arturo, Email: norman.cruz@usach.cl, Email: guillermo.palma@usach.cl, Email: david.zambrano@gmail.com, Email: avelino@fisica.ugto.mx. Interacting warm dark matter. United States. doi:10.1088/14757516/2013/05/034.
Cruz, Norman, Palma, Guillermo, Zambrano, David, and Avelino, Arturo, Email: norman.cruz@usach.cl, Email: guillermo.palma@usach.cl, Email: david.zambrano@gmail.com, Email: avelino@fisica.ugto.mx. 2013.
"Interacting warm dark matter". United States.
doi:10.1088/14757516/2013/05/034.
@article{osti_22282887,
title = {Interacting warm dark matter},
author = {Cruz, Norman and Palma, Guillermo and Zambrano, David and Avelino, Arturo, Email: norman.cruz@usach.cl, Email: guillermo.palma@usach.cl, Email: david.zambrano@gmail.com, Email: 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 nonlinear 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 goodnessoffit 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 goodnessoffit to data of the model, we find that a large variety of theirs values are well compatible with the observational data used.},
doi = {10.1088/14757516/2013/05/034},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 05,
volume = 2013,
place = {United States},
year = 2013,
month = 5
}

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