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arXiv · 1005.3811

LoCuSS: Shedding New Light on the Massive Lensing Cluster Abell 1689 - The View From Herschel

C. P. Haines·G. P. Smith·M. J. Pereira·E. Egami·S. M. Moran·E. Hardegree-Ullman·T. D. Rawle·M. Rex
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Abstract

We present wide-field Herschel/PACS observations of Abell 1689, a massive galaxy cluster at z=0.1832, from our Open Time Key Programme. We detect 39 spectroscopically confirmed 100micron-selected cluster members down to 1.5x10^10 Lsun. These galaxies are forming stars at rates in the range 1-10 Msun/yr, and appear to comprise two distinct populations: two-thirds are unremarkable blue, late-type spirals found throughout the cluster; the remainder are dusty red sequence galaxies whose star formation is heavily obscured with A(Halpha)~2 mag, and are found only in the cluster outskirts. The specific-SFRs of these dusty red galaxies are lower than the blue late-types, suggesting that the former are in the process of being quenched, perhaps via pre-processing, the unobscured star formation being terminated first. We also detect an excess of 100micron-selected galaxies extending ~6 Mpc in length along an axis that runs NE-SW through the cluster centre at >95% confidence. Qualitatively this structure is consistent with previous reports of substructure in X-ray, lensing, and near-infrared maps of this cluster, further supporting the view that this cluster is a dynamically active, merging system.

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C. P. Haines, G. P. Smith, M. J. Pereira, E. Egami, S. M. Moran, E. Hardegree-Ullman, T. D. Rawle, M. Rex. 2010-05-20. LoCuSS: Shedding New Light on the Massive Lensing Cluster Abell 1689 - The View From Herschel. https://doi.org/10.1051/0004-6361/201014692

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