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Gemini and Chandra observations of Abell 586, a relaxed strong-lensing cluster

E. S. Cypriano·G. B. Lima Neto·L. Sodré Jr·Jean Paul Kneib·Luis E. Campusano
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Abstract

We analyze the mass content of the massive strong-lensing cluster Abell 586 ($z = 0.17$). We use optical data (imaging and spectroscopy) obtained with the Gemini Multi-Object Spectrograph (GMOS) mounted on the 8-m Gemini-North telescope, together with publicly available X-ray data taken with the \textit{Chandra} space telescope. Employing different techniques -- velocity distribution of galaxies, weak gravitational lensing, and X-ray spatially resolved spectroscopy -- we derive mass and velocity dispersion estimates from each of them. All estimates agree well with each other, within a 68% confidence level, indicating a velocity dispersion of 1000 -- 1250 \kms. The projected mass distributions obtained through weak-lensing and X-ray emission are strikingly similar, having nearly circular geometry. We suggest that Abell 586 is probably a truly relaxed cluster, whose last major merger occurred more than $\sim 4$ Gyr ago

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E. S. Cypriano, G. B. Lima Neto, L. Sodré Jr, Jean Paul Kneib, Luis E. Campusano. 2005-04-04. Gemini and Chandra observations of Abell 586, a relaxed strong-lensing cluster. https://doi.org/10.1086/430661

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