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arXiv · 1704.07614

No evidence for the evolution of mass density power-law index $\gamma$ from strong gravitational lensing observation

Jing-Lei Cui·Hai-Li Li·Xin Zhang
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Abstract

In this paper, we consider the singular isothermal sphere lensing model that has a spherically symmetric power-law mass distribution $\rho_{tot}(r)\sim r^{-\gamma}$. We investigate whether the mass density power-law index $\gamma$ is cosmologically evolutionary by using the strong gravitational lensing (SGL) observation, in combination with other cosmological observations. We also check whether the constraint result of $\gamma$ is affected by the cosmological model, by considering several simple dynamical dark energy models. We find that the constraint on $\gamma$ is mainly decided by the SGL observation and independent of the cosmological model, and we find no evidence for the evolution of $\gamma$ from the SGL observation.

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Jing-Lei Cui, Hai-Li Li, Xin Zhang. 2017-04-25. No evidence for the evolution of mass density power-law index $\gamma$ from strong gravitational lensing observation. https://doi.org/10.1007/s11433-017-9054-5

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