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arXiv · 1909.00090

Gaussian Process Estimation of Transition Redshift

J. F. Jesus·R. Valentim·A. A. Escobal·S. H. Pereira
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Abstract

This paper aims to put constraints on the transition redshift $z_t$, which determines the onset of cosmic acceleration, in cosmological-model independent frameworks. In order to do that, we use the non-parametric Gaussian Process method with $H(z)$ and SNe Ia data. The deceleration parameter reconstruction from $H(z)$ data yields $z_t=0.59^{+0.12}_{-0.11}$. The reconstruction from SNe Ia data assumes spatial flatness and yields $z_t=0.683^{+0.11}_{-0.082}$. These results were found with a Gaussian kernel and we show that they are consistent with two other kernel choices.

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J. F. Jesus, R. Valentim, A. A. Escobal, S. H. Pereira. 2019-08-30. Gaussian Process Estimation of Transition Redshift. https://doi.org/10.1088/1475-7516%2F2020%2F04%2F053

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