タイトル | Spectroscopic Confirmation of Two Massive Red-sequence-selected Galaxy Clusters at Z ~ Approximately Equal to 1.2 in the Sparcs-North Cluster Survey |
本文(外部サイト) | http://hdl.handle.net/2060/20080045434 |
著者(英) | Lacy, Mark; Majumdar, Subhabrata; Demarco, Ricardo; Gilbank, David; Muzzin, Adam; Blindert, Kris; Gardner, Jonathan P.; Yee, H.K.C.; Gladders, Mike; Wilson, Gillian; Lonsdale, Carol; Surace, Jason; Hoekstra, Henk |
著者所属(英) | NASA Goddard Space Flight Center |
発行日 | 2008-01-01 |
言語 | eng |
内容記述 | The Spitzer Adaptation of the Red-sequence Cluster Survey (SpARCS) is a deep z -band imaging survey covering the Spitzer SWIRE Legacy fields designed to create the first large homogeneously-selected sample of massive clusters at z > 1 using an infrared adaptation of the cluster red-sequence method. We present an overview of the northern component of the survey which has been observed with CFHT/MegaCam and covers 28.3 deg(sup 2). The southern component of the survey was observed with CTIO/MOSAICII, covers 13.6 deg(sup 2), and is summarized in a companion paper by Wilson et al. (2008). We also present spectroscopic confirmation of two rich cluster candidates at z approx. 1.2. Based on Nod-and- Shuffle spectroscopy from GMOS-N on Gemini there are 17 and 28 confirmed cluster members in SpARCS J163435+402151 and SpARCS J163852+403843 which have spectroscopic redshifts of 1.1798 and 1.1963, respectively. The clusters have velocity dispersions of 490 +/- 140 km/s and 650 +/- 160 km/s, respectively which imply masses (M(sub 200)) of (1.0 +/- 0.9) x 10(exp 14) Stellar Mass and (2.4 +/- 1.8) x 10(exp 14) Stellar Mass. Confirmation of these candidates as bonafide massive clusters demonstrates that two-filter imaging is an effective, yet observationally efficient, method for selecting clusters at z > 1. |
NASA分類 | Astrophysics |
権利 | Copyright, Distribution as joint owner in the copyright |
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