Project Dinos II: Redshift evolution of dark and luminous matter density profiles in strong-lensing elliptical galaxies across $0.1 < z < 0.9$

• DOI: 10.48550/arxiv.2408.10316
• Publication Date: 2024-08-19
• Authors: William Sheu; Anowar J. Shajib; Tommaso Treu; Alessandro Sonnen...; Simon Birrer; Michele Cappellari; Lindsay Oldham; Chin Yi Tan
• Keywords: Cosmology and Nongalactic Astrophysics (astro-ph.CO); Astrophysics of Galaxies (astro-ph.GA); FOS: Physical sciences; Astrophysics - Astrophysics of Galaxies; Astrophysics - Cosmology and Nongalactic Astrophysics

We present a new measurement of the dark and luminous matter distribution massive elliptical galaxies, their evolution with redshift, by combining strong lensing dynamical observables. Our sample 58 lens galaxies covers redshift range $0.090\leq z_{\rm l}\leq0.884$. By Hubble Space Telescope imaging previously observed velocity dispersion line-of-sight measurements, we decompose profile from perform Bayesian hierarchical analysis to constrain population-level properties both profiles. find that inner slope density ("cusp"; $\rho_{\rm DM}\propto r^{-\gamma_{\rm in}}$) is slightly steeper ($\mu_{\gamma_{\rm in}}=1.18^{+0.03}_{-0.03}$ at $z=0.35$ $\leq0.16$ intrinsic scatter) than standard Navarro$-$Frenk$-$White (NFW; $\gamma_{\rm in}=1$), an appreciable ($d\log(\gamma_{\rm in})/dz=-0.33\pm0.13$) consistent NFW-like distributions higher redshifts ($z\geq0.56$ for $\leq1\sigma$ consistency). Additionally, stellar mass-to-light ratio population level Salpeter initial mass function, small gradient ($\kappa_{*}(r)\propto r^{-\eta}$, $\overline{\eta}\leq9.4\times10^{-3}$), isotropic orbits. averaged total power-law within $0.25-4$ Einstein radii ($\overline{\gamma}=2.14\pm0.06$), internal mass-sheet transformation parameter $\overline{\lambda}=1.02\pm0.01$ no sheet. findings confirm validity models used time-delay cosmography. However, our results are in tension predictions hydrodynamical simulations such as IllustrisTNG, highlighting need better understand formation galaxies.