Weak Lensing Discovery and Tomography of a Cluster at z=0.68

D. Wittman; V. E. Margoniner; J. A. Tyson; J. G. Cohen; I. P. Dell'Antonio; A. C. Becker

doi:10.1086/378344

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arXiv · astro-ph/0210120

Weak Lensing Discovery and Tomography of a Cluster at z=0.68

D. Wittman·V. E. Margoniner·J. A. Tyson·J. G. Cohen·I. P. Dell'Antonio·A. C. Becker

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Abstract

We report the weak lensing discovery, spectroscopic confirmation, and weak lensing tomography of a massive cluster of galaxies at $z=0.68$, demonstrating that shear selection of clusters works at redshifts high enough to be cosmologically interesting. The mass estimate from weak lensing, $11.1 +- 2.8 x 10^{14} (r/Mpc)$ solar masses within projected radius r, agrees with that derived from the spectroscopy ($σ_v = 980 km s^{-1}$), and with the position of an arc which is likely to be a strongly lensed background galaxy. The redshift estimate from weak lensing tomography is consistent with the spectroscopy, demonstrating the feasibility of baryon-unbiased mass surveys. This tomographic technique will be able to roughly identify the redshifts of any dark clusters which may appear in shear-selected samples, up to z ~ 1.

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D. Wittman, V. E. Margoniner, J. A. Tyson, J. G. Cohen, I. P. Dell'Antonio, A. C. Becker. 2003-11-05. Weak Lensing Discovery and Tomography of a Cluster at z=0.68. https://doi.org/10.1086/378344

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