Revisiting Studies of the Statistical Property of a Strong Gravitational Lens System and Model-independent Constraint on the Curvature of the Universe

Understand

In this paper we use a recently compiled data set, which comprises 118 galactic-scale strong gravitational lensing (SGL) systems to constrain the statistic property of SGL system, as well as the curvature of universe without assuming any fiducial cosmological model.

• Based on the singular isothermal ellipsoid (SIE) model of SGL system, we obtain that the constrained curvature parameter $\Omega_{\rm k}$ is close to zero from the SGL data, which is consistent with the latest result of planck measurement.
• More interestingly, we find that the parameter $f$ in the SIE model is strongly correlated with the curvature $\Omega_{\rm k}$.
• Neglecting this correlation in the analysis will significantly overestimate the constraining power of SGL data on the curvature.