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@Article{KumarNuneYada:2019:TeWaDa,
               author = "Kumar, Suresh and Nunes, Rafael da Costa and Yadav, Santosh 
                         Kumar",
          affiliation = "{BITS Pilani} and {Instituto Nacional de Pesquisas Espaciais 
                         (INPE)} and {BITS Pilani}",
                title = "Testing the warmness of dark matter",
              journal = "Monthly Notices of the Royal Astronomical Society",
                 year = "2019",
               volume = "490",
               number = "1",
                pages = "1406--1414",
                month = "Nov.",
             keywords = "cosmological parameters, dark energy, dark matter, cosmology: 
                         observations.",
             abstract = "Dark matter (DM) as a pressureless perfect fluid provides a good 
                         fit of the standard Lambda cold dark matter (Lambda CDM) model to 
                         the astrophysical and cosmological data. In this paper, we 
                         investigate two extended properties of DM: a possible time 
                         dependence of the equation of state of DM via 
                         Chevallier-Polarski-Linder parametrization, w(dm) = w(dm0) + 
                         w(dm1)(1 - a), and the constant non-null sound speed (c) over cap 
                         (2)(s,dm). We analyse these DM properties on top of the base 
                         Lambda CDM model by using the data from Planck cosmic microwave 
                         background (CMB) temperature and polarization anisotropy, baryonic 
                         acoustic oscillations (BAOs), and the local value of the Hubble 
                         constant from the Hubble Space Telescope (HST). We find new and 
                         robust constraints on the extended free parameters of DM. The most 
                         tight constraints are imposed by CMB+BAO data, where the three 
                         parameters w(dm0), w(dm1), and (c) over cap (2)(s,dm) are, 
                         respectively, constrained to be less than 1.43 x 10(-3), 1.44 x 
                         10(-3), and 1.79 x 10(-6) at 95 per cent CL. All the extended 
                         parameters of DM show consistency with zero at 95 per cent CL, 
                         indicating no evidence beyond the CDM paradigm. We notice that the 
                         extended properties of DM significantly affect several parameters 
                         of the base Lambda CDM model. In particular, in all the analyses 
                         performed here, we find significantly larger mean values of H-0 
                         and lower mean values of sigma(8) in comparison to the base Lambda 
                         CDM model. Thus, the well-known H-0 and sigma(8) tensions might be 
                         reconciled in the presence of extended DM parameters within the 
                         Lambda CDM framework. Also, we estimate the warmness of DM 
                         particles as well as its mass scale, and find a lower bound: 
                         similar to 500 eV from our analyses.",
                  doi = "10.1093/mnras/stz2676",
                  url = "http://dx.doi.org/10.1093/mnras/stz2676",
                 issn = "0035-8711 and 1365-2966",
             language = "en",
           targetfile = "kumar_testing.pdf",
        urlaccessdate = "27 abr. 2024"
}


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