What Do Gravitational Lens Time Delays Measure?
نویسندگان
چکیده
منابع مشابه
What Do Gravitational Lens Time Delays Measure?
Gravitational lens time delays depend on the Hubble constant, the observed image positions, and the surface mass density of the lens in the annulus between the images. Simple time delay lenses like PG1115+080, SBS1520+530, B1600+434, PKS1830–211 and HE2149–2745 have H 0 = A(1 − κ) + Bκ(η − 1) where the two coefficients A ≃ 90 km/s Mpc and B ≃ 10 km/s Mpc depend on the measured delays and the ob...
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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 H0 is the mean surface mass density 〈κ〉 (in units of the critical density for gravitational lensing) of the lens galaxy at the radius of the lensed images. More centrally concentrated mass distribution...
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ژورنال
عنوان ژورنال: The Astrophysical Journal
سال: 2002
ISSN: 0004-637X,1538-4357
DOI: 10.1086/342476