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تسجيل مستخدم جديدCosmological constraints on alternative model to Chaplygin fluid revisited
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In this work we explore an alternative phenomenological model to Chaplygin gas proposed by H. Hova et. al., consisting on a modification of a perfect fluid, to explain the dynamics of dark matter and dark energy at cosmological scales immerse in a flat or curved universe. Adopting properties similar to a Chaplygin gas, the proposed model is a mixture of dark matter and dark energy components parameterized by only one free parameter denoted as $mu$. We focus on contrasting this model with the most recent cosmological observations of Type Ia Supernovae and Hubble parameter measurements. Our joint analysis yields a value $mu = 0.843^{+0.014}_{-0.015},$ ($0.822^{+0.022}_{-0.024}$) for a flat (curved) universe. Furthermore, with these constraints we also estimate the deceleration parameter today $q_0=-0.67 pm 0.02,(-0.51pm 0.07)$, the acceleration-deceleration transition redshift $z_t=0.57pm 0.04, (0.50 pm 0.06)$, and the universe age $t_A = 13.108^{+0.270}_{-0.260},times (12.314^{+0.590}_{-0.430}),$Gyrs. We also report a best value of $Omega_k = 0.183^{+0.073}_{-0.079}$ consistent at $3sigma$ with the one reported by Planck Collaboration. Our analysis confirm the results by Hova et al, this Chaplygin gas-like is a plausible alternative to explain the nature of the dark sector of the universe.
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