Current constraints on the epoch of cosmic acceleration |
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| Authors: | B SantosJC Carvalho JS Alcaniz |
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| Institution: | a Departamento de Astronomia, Observatório Nacional, 20921-400 Rio de Janeiro, RJ, Brazil
b Departamento de Física, Universidade Federal do Rio Grande do Norte, 59072-970 Natal, RN, Brazil |
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| Abstract: | The cosmographic expansion history of the universe is investigated by using the 557 type Ia supernovae from the Union2 Compilation set along with the current estimates involving the product of the CMB acoustic scale ?A and the BAO peak at two different redshifts. Using a well-behaved parameterization for the deceleration parameter, q(z) = q0 + q1z/(1 + z), we estimate the accelerating redshift zacc = −q0/(q0 + q1) (at which the universe switches from deceleration to acceleration) and investigate the influence of a non-vanishing spatial curvature on these estimates. We also use the asymptotic value of q(z) at high-z to place more restrictive bounds on the model parameters q0 and q1, which results in a more precise determination of the epoch of cosmic acceleration. |
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| Keywords: | Cosmology Cosmic acceleration Cosmography |
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