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arXiv · 0910.5823

Gravitational lenses as cosmic rulers: density of dark matter and dark energy from time delays and velocity dispersions

Danuta Paraficz·Jens Hjorth
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Abstract

We show that a cosmic standard ruler can be constructed from the joint measurement of the time delay (dt) between gravitationally lensed quasar images and the velocity dispersion (sigma^2) of the lensing galaxy. This is specifically shown, for a singular isothermal sphere lens, where the angular diameter distance to the lens is proportional to dt/sigma^2. Using MCMC simulations we illustrate the constraints set in the density of dark matter and dark energy plane from future observations.

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Danuta Paraficz, Jens Hjorth. 2009-10-30. Gravitational lenses as cosmic rulers: density of dark matter and dark energy from time delays and velocity dispersions. https://doi.org/10.1051/0004-6361%2F200913307

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