Sign on

SAO/NASA ADS Astronomy Abstract Service

· Find Similar Abstracts (with default settings below)
· Electronic Refereed Journal Article (HTML)
· Full Refereed Journal Article (PDF/Postscript)
· arXiv e-print (arXiv:astro-ph/0608499)
· On-line Data
· References in the article
· Citations to the Article (40) (Citation History)
· Refereed Citations to the Article
· SIMBAD Objects (8)
· NED Objects (2)
· Also-Read Articles (Reads History)
·
· Translate This Page
Title:
Using Weak-Lensing Dilution to Improve Measurements of the Luminous and Dark Matter in A1689
Authors:
Medezinski, Elinor; Broadhurst, Tom; Umetsu, Keiichi; Coe, Dan; Benítez, Narciso; Ford, Holland; Rephaeli, Yoel; Arimoto, Nobuo; Kong, Xu
Affiliation:
AA(School of Physics and Astronomy, Tel Aviv University, Israel.), AB(School of Physics and Astronomy, Tel Aviv University, Israel.), AC(Institute of Astronomy and Astrophysics, Academia Sinica, P.O. Box 23-141, Taipei 106, Taiwan.), AD(Physics and Astronomy Department, The Johns Hopkins University, Baltimore Maryland; Instituto de Astrofísica de Andalucía (CSIC), Granada, Spain.), AE(Instituto de Astrofísica de Andalucía (CSIC), Granada, Spain.), AF(Physics and Astronomy Department, The Johns Hopkins University, Baltimore Maryland.), AG(School of Physics and Astronomy, Tel Aviv University, Israel.), AH(National Astronomical Observatory of Japan, Mitaka 181-8588, Japan.), AI(Center for Astrophysics, University of Science and Technology of China, Hefei, 230026, Anhui, China.)
Publication:
The Astrophysical Journal, Volume 663, Issue 2, pp. 717-733. (ApJ Homepage)
Publication Date:
07/2007
Origin:
UCP
Astronomy Keywords:
Cosmology: Observations, Cosmology: Gravitational Lensing, Galaxies: Clusters: Individual: Name: Abell 1689
DOI:
10.1086/518638
Bibliographic Code:
2007ApJ...663..717M

Abstract

The E/S0 sequence of a cluster defines a boundary redward of which a reliable weak-lensing signal can be obtained from background galaxies, uncontaminated by cluster members. For bluer colors, both background and cluster members are present, reducing the average distortion signal by the proportion of unlensed cluster members. In deep Subaru and HST/ACS images of A1689, the tangential distortion of galaxies with bluer colors falls rapidly toward the cluster center relative to lensing signal of the red background. We use this dilution effect to derive the cluster light profile and luminosity function to large radius, with the advantage that no subtraction of far-field background counts is required. The light profile declines smoothly to the limit of the data, r<2 h-1 Mpc, with a constant slope, dlog(L)/dlog(r)=-1.12+/-0.06, unlike the lensing mass profile which steepens continuously with radius, so that M/L peaks at an intermediate radius, ~=100 h-1 kpc. A flatter behavior is found for the more physically meaningful ratio of dark matter to stellar matter when accounting for the color-mass relation of cluster members. The cluster luminosity function has a flat slope, α=-1.05+/-0.05, independent of radius and with no faint upturn to Mi'<-12. We establish that the very bluest objects are negligibly contaminated by the cluster [(V-i')AB<0.2], because their distortion profile rises toward the center following the red background, but offset higher by ~=20%. This larger amplitude is consistent with the greater estimated depth of the faint blue galaxies, <z>~2 compared to <z>~0.85 for the red background, a purely geometric effect related to cosmological parameters. Finally, we improve on our earlier mass profile by combining both the red and blue background populations, clearly excluding low-concentration CDM profiles.
Bibtex entry for this abstract   Preferred format for this abstract (see Preferences)
   

Find Similar Abstracts:

Use: Authors
Title
Keywords (in text query field)
Abstract Text
Return: Query Results Return    items starting with number
Query Form
Database: Astronomy
Physics
arXiv e-prints