Constraints on cosmological models from strong gravitational lensing systems

Abstract

Strong lensing has developed into an important astrophysical tool for probing both cosmology and galaxies (their structure, formation, and evolution). Using the gravitational lensing theory and cluster mass distribution model, we try to collect a relatively complete observational data concerning the Hubble constant independent ratio between two angular diameter distances D ds /D s from various large systematic gravitational lens surveys and lensing by galaxy clusters combined with X-ray observations, and check the possibility to use it in the future as complementary to other cosmological probes. On one hand, strongly gravitationally lensed quasar-galaxy systems create such a new opportunity by combining stellar kinematics (central velocity dispersion measurements) with lensing geometry (Einstein radius determination from position of images). We apply such a method to a combined gravitational lens data set including 70 data points from Sloan Lens ACS (SLACS) and Lens Structure and Dynamics survey (LSD). On the other hand, a new sample of 10 lensing galaxy clusters with redshifts ranging from 0.1 to 0.6 carefully selected from strong gravitational lensing systems with both X-ray satellite observations and optical giant luminous arcs, is also used to constrain three dark energy models (ΛCDM, constant w and CPL) under a flat universe assumption. For the full sample (n = 80) and the restricted sample (n = 46) including 36 two-image lenses and 10 strong lensing arcs, we obtain relatively good fitting values of basic cosmological parameters, which generally agree with the results already known in the literature. This results encourages further development of this method and its use on larger samples obtained in the future.

Constraints on holographic cosmologies from strong lensing systems

“…In what concern to data manipulation, and following [29], we selected 59 strong lens systems from the Sloan Lens ACS Survey (SLACS, [51]) and the Lens Structure and Dynamic survey (LSD, [43,44]), and 11 from CfA-Arizona Space Telescope LEns Survey [72]. SLACS systems where selected from the Sloan Digital Sky Survey (SDSS) based on the presence of absorption-dominated galaxy continuum at one redshift and emission lines at another higher redshift ( [50]).…”

“…The authors of [29] and [78] have used a SIS model and an extra factor f E to account for: (i) systematical errors in the observed velocity dispersion, (ii) differences between θ E obtained from SIS and SIE and image separation.…”

“…The idea of using such systems was discussed first in [27] and also in [28]. We use the data set first used in [29] (see also [30]) consisting in 70 data points from Sloan Lens ACS (SLACS), and galaxy clusters from optical and X-ray surveys [53,54].…”

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

“…where θ E is the Einstein radius, σ c is the central velocity dispersion of the lensing galaxy , c is the speed of light and f is a phenomenological coefficient which includes several systematic errors caused by: the difference between the observed stellar velocity dispersion and that of the SIS model, the assumption of SIS model in calculating the theoretical Einstein radius, and the softened isothermal sphere potentials (Ofek et al 2003;Cao et al 2012). For the standard SIS model, the coefficient parameter reduces to f = 1.…”

Constraints on Dark Energy Models from Selected Galaxy Clusters (S-Z + X-Ray Data) and Gravitational Lensing Data

“…Θ is the vector of the parameters of the cosmological model [16]. Here, we use a sample of 80 strong lensing systems by [10] which contains 70 data points from SLACS and LSD and 10 data points from galaxy clusters.…”