# The Hubble Constant from Gravitational Lens Time Delays

@inproceedings{Kochanek2003TheHC, title={The Hubble Constant from Gravitational Lens Time Delays}, author={Christopher S. Kochanek and P. S'ari Harvard-Smithsonian Center for Astrophysics and Mit}, year={2003} }

There are now 10 firm time delay measurements in gravitational lenses. The physics of time delays is well understood, and the only important variable for interpreting the time delays to determine H_0 is the mean surface mass density(in units of the critical density for gravitational lensing) of the lens galaxy at the radius of the lensed images. More centrally concentrated mass distributions with lowerpredict higher Hubble constants, with H_0~1-to lowest order. While we cannot determinedirectly… Expand

#### 13 Citations

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Time delays of gravitationally lensed sources can be used to constrain the mass model of a deflector and determine cosmological parameters. We here present an analysis of the time-delay distribution… Expand

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We investigate the effect of the redshift drift in strong gravitational lensing. The redshift drift produces a time variation of $i)$ the apparent position of a lensed source and $ii)$ the time delay… Expand

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