2003/10/23 by Prasenjit Saha · 1 citation
Physics and Astronomy · #Astronomy and Astrophysical Research #Galaxies: Formation, Evolution, Phenomena #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.1051/0004-6361:20034184
published as Astron.Astrophys. 414 (2004) 425-428 · To appear in A&A
arxiv created 2003/10/23 · openalex publication_date 2004/01/19 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We can think of a lensed quasar as taking the Hubble time, shrinking it by ~10-11, and then presenting the result to us as a time delay; the shrinking factor is of the order of fractional sky-area that the lens occupies. This cute fact is a straightforward consequence of lensing theory, and enables a simple rescaling of time delays. Observed time delays have a 40-fold range, but after rescaling the range reduces to 5-fold. The latter range depends on details of the lens and lensing configuration--for example, quads have systematically shorter rescaled time delays than doubles--and is as expected from a simple model. The hypothesis that observed time-delay lenses all come from a generalized-isothermal family can be ruled out. But there is no indication of drastically different populations either.