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تسجيل مستخدم جديدStrong Bounds on Sum of Neutrino Masses in a 12 Parameter Extended Scenario with Non-Phantom Dynamical Dark Energy ($w(z)geq -1$)
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We obtained constraints on a 12 parameter extended cosmological scenario including non-phantom dynamical dark energy (NPDDE) with CPL parametrization. We also include the six $Lambda$CDM parameters, number of relativistic neutrino species ($N_{textrm{eff}}$) and sum over active neutrino masses ($sum m_{ u}$), tensor-to-scalar ratio ($r_{0.05}$), and running of the spectral index ($n_{run}$). We use CMB Data from Planck 2015; BAO Measurements from SDSS BOSS DR12, MGS, and 6dFS; SNe Ia Luminosity Distance measurements from the Pantheon Sample; CMB B-mode polarization data from BICEP2/Keck collaboration (BK14); Planck lensing data; and a prior on Hubble constant ($73.24pm1.74$ km/sec/Mpc) from local measurements (HST). We have found strong bounds on the sum of the active neutrino masses. For instance, a strong bound of $sum m_{ u} <$ 0.123 eV (95% C.L.) comes from Planck+BK14+BAO. Although we are in such an extended parameter space, this bound is stronger than a bound of $sum m_{ u} <$ 0.158 eV (95% C.L.) obtained in $Lambda textrm{CDM}+sum m_{ u}$ with Planck+BAO. Varying $A_{textrm{lens}}$ instead of $r_{0.05}$ however leads to weaker bounds on $sum m_{ u}$. Inclusion of the HST leads to the standard value of $N_{textrm{eff}} = 3.045$ being discarded at more than 68% C.L., which increases to 95% C.L. when we vary $A_{textrm{lens}}$ instead of $r_{0.05}$, implying a small preference for dark radiation, driven by the $H_0$ tension.
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