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Discovery of a Galaxy Cluster via Weak Lensing

Wittman, D. and Tyson, J. A. and Margoniner, V. E. and Cohen, J. G. and Dell’Antonio, I. P. (2001) Discovery of a Galaxy Cluster via Weak Lensing. Astrophysical Journal, 557 (2). L89-L92. ISSN 0004-637X. doi:10.1086/323173.

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We report the discovery of a cluster of galaxies via its weak gravitational lensing effect on background galaxies, the first spectroscopically confirmed cluster to be discovered through its gravitational effects rather than by its electromagnetic radiation. This fundamentally different selection mechanism promises to yield mass-selected, rather than baryon- or photon-selected, samples of these important cosmological probes. We have confirmed this cluster with spectroscopic redshifts of 15 members at z= 0.276, with a velocity dispersion of 615 km s^(-1). We use the tangential shear as a function of source photometric redshift to estimate the lens redshift independently and find z_l = 0.30 ± 0.08. The good agreement with the spectroscopy indicates that the redshift evolution of the mass function may be measurable from the imaging data alone in shear-selected surveys.

Item Type:Article
Related URLs:
URLURL TypeDescription Paper
Wittman, D.0000-0002-0813-5888
Cohen, J. G.0000-0002-8039-4673
Additional Information:© 2001 The American Astronomical Society. Received 2001 April 5; accepted 2001 July 10; published 2001 July 23. We thank P. Guhathakurta for providing spectroscopic redshifts outside the cluster and the CTIO staff for their help with the BTC project and for their upgrading and maintenance of the delivered image quality of the Blanco telescope. The CTIO is a division of National Optical Astronomy Observatory (NOAO), which is operated by the Association of Universities for Research in Astronomy, Inc., under cooperative agreement with the National Science Foundation (NSF). BTC construction was partially funded by the NSF.
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Subject Keywords:galaxies: clusters: general—gravitational lensing
Issue or Number:2
Record Number:CaltechAUTHORS:20190524-093701611
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Official Citation:D. Wittman et al 2001 ApJ 557 L89
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:95780
Deposited By: Tony Diaz
Deposited On:24 May 2019 16:42
Last Modified:16 Nov 2021 17:15

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