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arXiv · 2206.09856

A Mass Model for the Lensing Cluster SDSS J1004+4112: Constraints From the Third Time Delay

R. Forés-Toribio·J. A. Muñoz·C. S. Kochanek·E. Mediavilla
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Abstract

We have built a new model for the lens system SDSS J1004+4112 including the recently measured time delay of the fourth quasar image. This time delay has a strong influence on the inner mass distribution of the lensing cluster ($\rho \propto r^{-\alpha}$) allowing us to determine $\alpha=1.18^{+0.02(+0.11)}_{-0.03(-0.18)}$ at the 68% (95%) confidence level in agreement with hydrodynamical simulations of massive galaxy clusters. We find an offset between the brightest cluster galaxy (BCG) and the dark matter halo of $3.8^{+0.6(+1.4)}_{-0.7(-1.3)}$ kpc at 68% (95%) confidence which is compatible with other galaxy cluster measurements. As an observational challenge, the estimated time delay between the leading image C and the faint (I=24.7) fifth image E is roughly 8 yr.

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R. Forés-Toribio, J. A. Muñoz, C. S. Kochanek, E. Mediavilla. 2022-06-20. A Mass Model for the Lensing Cluster SDSS J1004+4112: Constraints From the Third Time Delay. https://doi.org/10.3847/1538-4357/ac8c40

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