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arXiv · 1102.3254

Observational constraints on decaying vacuum dark energy model

M. L. Tong·H. Noh
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Abstract

The decaying vacuum model (DV), treating dark energy as a varying vacuum, has been studied well recently. The vacuum energy decays linearly with the Hubble parameter in the late-times, $ρ_Λ(t) \propto H(t)$, and produces the additional matter component. We constrain the parameters of the DV model using the recent data-sets from supernovae, gamma-ray bursts, baryon acoustic oscillations, CMB, the Hubble rate and x-rays in galaxy clusters. It is found that the best fit of matter density contrast $Ω_m$ in the DV model is much lager than that in $Λ$CDM model. We give the confidence contours in the $Ω_m-h$ plane up to $3σ$ confidence level. Besides, the normalized likelihoods of $Ω_m$ and $h$ are presented, respectively. %

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M. L. Tong, H. Noh. 2011-02-16. Observational constraints on decaying vacuum dark energy model. https://doi.org/10.1140/epjc%2Fs10052-011-1586-5

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