http://arxiv.org/abs/1906.04107
Inspired by a new compilation of strong lensing systems (SLS), which consist of 205 points in the redshift range $0.0625< z_{l} < 0.958$ for the lens galaxy and $0.196< z_{s} < 3.595$ for the source, we constrain three models that generate a late cosmic acceleration: the $\omega$-cold dark matter model, the Chevallier-Polarski-Linder and the Jassal-Bagla-Padmanabhan parametrizations. Our compilation contains only those systems with early type galaxies acting as lenses, with spectroscopically measured stellar velocity dispersions, estimated Einstein radius of each system, and both the lens and source redshifts. We assume an axially symmetric mass distribution in the lens equation, using a correction to alleviate differences between the measured velocity dispersion ($\sigma$) and the dark matter halo velocity dispersion ($\sigma_{DM}$) as well as other systematic errors that may affect the measurements. To investigate the impact of some observables, such as the velocity dispersion, the Einstein radius and the redshift interval probed by the lens galaxies, we have considered different sub-samples to constrain the cosmological parameters of each model. Our results show that cosmological constraints are very sensitive to the selected data: some cases show convergence problems in the estimation of cosmological parameters (e.g. systems with observed distance ratio $D^{obs}<0.5$), others show high values for the chi-square function (e.g. systems with a lens equation $D^{obs} >1$ or high velocity dispersion $\sigma > 276$ km s$^{-1}$). Model selection criteria show that using SLS, the $\omega$-cold dark matter and Chevallier-Polarski-Linder models are preferred in different regions of the data.
M. Amante, J. Magaña, V. Motta, et. al.
Tue, 11 Jun 19
7/60
Comments: 18 pages, 18 figures, submitted to MNRAS
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