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arXiv 1809.06378astro-ph.COastro-ph.GA
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高信噪比Planck星系团候选星系的高置信度光学计算

High Confidence Optical Confirmations Among the High Signal-to-Noise Planck Cluster Candidates

Steven Boada, John P. Hughes, Felipe Menanteau, Peter Doze, L. Felipe Barrientos, L. Infante

摘要:

本文报道了从第二个全天\textit{Planck} Sunyaev-Zel'dovich(SZ)星表(PSZ 2)的高信噪比($>5$ - $σ$)端新发现的星系团。这些星团是在2014年至2017年期间由基特峰国家天文台4米Mayall望远镜拍摄的深层光学成像中确定的。在这里,我们专注于最高丰富度的系统,并确定星系团通过maxBCG算法和视觉图像检查相结合。星系团被认为是确认,如果他们都丰富和空间重合($\lesssim 6'$)与报告的PSZ 2的位置。在观测到的85个包含未经证实的PSZ 2候选者的区域中,我们发现了15个(占观测样本的17.6%)对应的星系团($ 0.13 < z < 0.78$),其中12个以前未被识别为对应物。为了解释这种低识别率,我们考虑了三种可能的情况:集群(1)主要位于低z,(2)主要位于高z,或(3)位于具有高对象密度的场中。这些情况都不能单独解释在高信噪比的PSZ 2未经证实的候选者中丰富的星系团的低纯度。

英文摘要:

We report on newly identified galaxy clusters from the high signal-to-noise ($>5$-$σ$) end of the second all-sky \textit{Planck} Sunyaev-Zel'dovich (SZ) catalog (PSZ2). The clusters are identified in deep, optical imaging from the Kitt Peak National Observatory 4m Mayall telescope taken between 2014 and 2017. Here we focus on the highest richness systems, and identify galaxy clusters through a combination of the maxBCG algorithm and visual image inspection. Galaxy clusters are considered to be confirmed if they are both rich and spatially coincident ($\lesssim 6'$) with the reported PSZ2 position. Of the 85 fields containing unconfirmed PSZ2 candidates observed, we find 15 (17.6% of the observed sample) corresponding galaxy clusters ($ 0.13 < z < 0.78$), 12 of which are previously unrecognized as counterparts. To explain this low identification fraction, we consider three possible scenarios: that clusters are (1) mostly at low-z, (2) mostly at high-z, or (3) located in fields with high object density. None of these scenarios alone can account for the low purity of rich galaxy clusters among the high signal-to-noise PSZ2 unconfirmed candidates.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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