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arXiv · 1501.05051

Resolving the Merging Planck Cluster PLCK G147.3-16.6 with GISMO

T. Mroczkowski·A. Kovács·E. Bulbul·J. Staguhn·D. J. Benford·T. E. Clarke·R. J. van Weeren·H. T. Intema·S. Randall
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Abstract

The $Planck$ satellite has recently completed an all-sky galaxy cluster survey exploiting the thermal Sunyaev-Zel'dovich (SZ) effect to locate some of the most massive systems observable. With a median redshift of $\left =0.22$, the clusters found by $Planck$ at $z>0.3$ are proving to be exceptionally massive and/or disturbed systems. One notable $Planck$ discovery at $z=0.645$, PLCK G147.3-16.6, has a dual core and hosts a radio halo, indicating it is likely in the process of merging. We present a 16."5 resolution SZ observation of this high-$z$ merger using the Goddard-IRAM Superconducting 2 Millimeter Observer (GISMO), and compare it to X-ray follow-up observations with XMM-$Newton$. We find the SZ pressure substructure is offset from the core components seen in X-ray. We interpret this offset as possible line of sight temperature or density substructure due to the on-going merger.

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T. Mroczkowski, A. Kovács, E. Bulbul, J. Staguhn, D. J. Benford, T. E. Clarke, R. J. van Weeren, H. T. Intema, S. Randall. 2015-06-09. Resolving the Merging Planck Cluster PLCK G147.3-16.6 with GISMO. https://doi.org/10.1088/2041-8205%2F808%2F1%2Fl6

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