NOAO >   Observing Info >   Approved Programs >   2008A-0356

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Proposal Information for 2008A-0356


PI: Rachel Mandelbaum, Institute for Advanced Study, rmandelb@sns.ias.edu
Address: School of Natural Sciences, Einstein Drive, Princeton, NJ 08540, USA

CoI: Reiko Nakajima, University of Pennsylvania
CoI: Gary Bernstein, University of Pennsylvania
CoI: Megan Donahue, Michigan State University
CoI: Charles R. Keeton, Rutgers University
CoI: John P. Hughes, Rutgers University
CoI: Neta Bahcall, Princeton University
CoI: Tim Schrabback, Universitaet Bonn
CoI: Nikhil Padmanabhan, Lawrence Berkeley National Laboratory
CoI: Satoshi Miyazaki, National Astronomical Obs of Japan (NAOJ), Subaru Telescope
CoI: Andrey V. Kravtsov, University of Chicago
CoI: Kenneth Cavagnolo, Michigan State University
CoI: Brian McLeod, Harvard-Smithsonian Center for Astrophysics

Title: Normalization and scatter of the mass-temperature relation for supermassive galaxy clusters

Abstract: We propose a high-accuracy survey of the 20 most massive clusters in the northern hemisphere at 0.15<z<0.3, to yield a uniform catalog of X- ray, galaxy, and dark-matter properties (from weak gravitational lensing, WL). All quantities will be determined with high S/N and low systematic errors. The major scientific goals are to (a) determine the normalization \em and scatter in the mass-temperature relation for massive clusters, which is essential for the use of clusters to constrain cosmological parameters, and (b) use the relations between WL mass, X-ray temperature, and other structural variables to validate numerical models of cluster evolution. There has to date been no cluster lensing survey with sufficiently large sample size and sufficiently low random and systematic errors to infer the intrinsic component of the M-T scatter. We expect to determine the scatter in the M-T relation to +/- 5%. All targets have existing Chandra, XMM, and ASCA X-ray data, HST strong-lensing imaging, and most have existing good-seeing images from Subaru. Our project will complete the WL imaging and, with this proposal, obtain multiband Mosaic observations for photometric redshifts. Uniform photo-z's are essential to properly calibrate the WL data and isolate the (unlensed) cluster member galaxies.


National Optical Astronomy Observatory, 950 North Cherry Avenue, P.O. Box 26732, Tucson, Arizona 85726, Phone: (520) 318-8000, Fax: (520) 318-8360



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