Wide-field weak lensing by RX J1347-1145

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We present an analysis of weak-lensing observations for RX J1347-1145 over a 43' × 43' field taken in B and R filters on the Blanco 4 m telescope at CTIO. RX J1347-1145 is a massive cluster at redshift z = 0.45. Using a population of galaxies with 20 < R < 26, we detect a weak-lensing signal at the p < 0.0005 level, finding best-fit parameters of σv = 1400 km s-1 for a singular isothermal sphere model and r200 = 3.5 Mpc with c = 15 for an NFW model in an Ωm = 0.3, ΩΛ = 0.7 cosmology. In addition, a mass-to-light ratio M/LR = 90 ± 20 M/LR was determined. These values are consistent with the previous weak-lensing study of RX J1347-1145 by Fischer & Tyson, giving strong evidence that systemic bias was not introduced by the relatively small field of view in that study. Our best-fit parameter values are also consistent with recent X-ray studies by Allen et al. and Ettori et al. but are not consistent with recent optical velocity dispersion measurements by Cohen & Kneib.

Original Citation

Kling T.P., Dell'Antonio I., Wittman D., Tyson J.A. (2005). Wide-field weak lensing by RX J1347-1145. Astrophysical Journal, 625(2), 643-655. https://doi.org/10.1086/428891