Astronomy and Astrophysics – Astrophysics
Scientific paper
2003-06-05
Astrophys.J.595:29-42,2003
Astronomy and Astrophysics
Astrophysics
30 pages including 6 figures, to be published in ApJ
Scientific paper
10.1086/377356
We introduce a self-similar mass model for early-type galaxies, and constrain it using the aperture mass-radius relations determined from the geometries of 22 gravitational lenses. The model consists of two components: a concentrated component which traces the light distribution, and a more extended power-law component (rho propto r^-n) which represents the dark matter. We find that lens galaxies have total mass profiles which are nearly isothermal, or slightly steeper, on the several-kiloparsec radial scale spanned by the lensed images. In the limit of a single-component, power-law radial profile, the model implies n=2.07+/-0.13, consistent with isothermal (n=2). Models in which mass traces light are excluded at >99 percent confidence. An n=1 cusp (such as the Navarro-Frenk-White profile) requires a projected dark matter mass fraction of f_cdm = 0.22+/-0.10 inside 2 effective radii. These are the best statistical constraints yet obtained on the mass profiles of lenses, and provide clear evidence for a small but non-zero dark matter mass fraction in the inner regions of early-type galaxies. In addition, we derive the first strong lensing constraint on the relation between stellar mass-to-light ratio (Upsilon) and galaxy luminosity (L): Upsilon propto L^[0.14 (+0.16)(-0.12)], which is consistent with the relation suggested by the fundamental plane. Finally, we apply our self-similar mass models to current problems regarding the interpretation of time delays and flux ratio anomalies in gravitational lens systems.
Keeton Charles R.
Kochanek Chris S.
Rusin David
No associations
LandOfFree
Self-Similar Models for the Mass Profiles of Early-type Lens Galaxies does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Self-Similar Models for the Mass Profiles of Early-type Lens Galaxies, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Self-Similar Models for the Mass Profiles of Early-type Lens Galaxies will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-24407