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Reconstruction of a Deceleration Parameter from the Latest Type Ia Supernovae Gold Dataset

Lixin Xu·Chengwu Zhang·Baorong Chang·Hongya Liu
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Abstract

In this paper, a parameterized deceleration parameter $q(z)= 1/2 - a/(1 + z)^b$ is reconstructed from the latest type Ia supernovae gold dataset. It is found out that the transition redshift from decelerated expansion to accelerated expansion is at $z_T=0.35^{+0.14}_{-0.07}$ with $1σ$ confidence level in this parameterized deceleration parameter. And, the best fit values of parameters in $1σ$ errors are $a=1.56^{+0.99}_{-0.55}$ and $b=3.82^{+3.70}_{-2.27}$.

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Lixin Xu, Chengwu Zhang, Baorong Chang, Hongya Liu. 2007-01-17. Reconstruction of a Deceleration Parameter from the Latest Type Ia Supernovae Gold Dataset. https://arxiv.org/abs/astro-ph/0701490

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