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arXiv · 1411.0317

Measurements of the Sunyaev-Zel'dovich Effect in MACS J0647.7+7015 and MACS J1206.2-0847 at High Angular Resolution with MUSTANG

Alexander H. Young·Tony Mroczkowski·Charles Romero·Jack Sayers·Italo Balestra·Tracy E. Clarke·Nicole Czakon·Mark Devlin·Simon R. Dicker·Chiara Ferrari·Marisa Girardi·Sunil Golwala·Huib Intema·Phillip M. Korngut·Brian S. Mason·Amata Mercurio·Mario Nonino·Erik D. Reese·Piero Rosati·Craig Sarazin·Keiichi Umetsu
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Abstract

We present high resolution (9$^{\prime \prime}$) imaging of the Sunyaev-Zel'dovich Effect (SZE) toward two massive galaxy clusters, MACS J0647.7+7015 ($z=0.591$) and MACS J1206.2-0847 ($z=0.439$). We compare these 90 GHz measurements, taken with the MUSTANG receiver on the Green Bank Telescope, with generalized Navarro-Frenk-White (gNFW) models derived from Bolocam 140 GHz SZE data as well as maps of the thermal gas derived from {\it Chandra} X-ray observations. For MACS J0647.7+7015, we find a gNFW profile with core slope parameter $γ= 0.9$ fits the MUSTANG image with $χ^{2}_{red}=1.005$ and probability to exceed (PTE) = 0.34. For MACS J1206.2-0847, we find $γ=0.7$, $χ^{2}_{red}=0.993$, and PTE = 0.70. In addition, we find a significant ($>$3-$σ$) residual SZE feature in MACS J1206.2-0847 coincident with a group of galaxies identified in VLT data and filamentary structure found in a weak-lensing mass reconstruction. We suggest the detected sub-structure may be the SZE decrement from a low mass foreground group or an infalling group. GMRT measurements at 610 MHz reveal diffuse extended radio emission to the west, which we posit is either an AGN-driven radio lobe, a bubble expanding away from disturbed gas associated with the SZE signal, or a bubble detached and perhaps re-accelerated by sloshing within the cluster. Using the spectroscopic redshifts available, we find evidence for a foreground ($z=0.423$) or infalling group, coincident with the residual SZE feature.

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Alexander H. Young, Tony Mroczkowski, Charles Romero, Jack Sayers, Italo Balestra, Tracy E. Clarke, Nicole Czakon, Mark Devlin, Simon R. Dicker, Chiara Ferrari, Marisa Girardi, Sunil Golwala, Huib Intema, Phillip M. Korngut, Brian S. Mason, Amata Mercurio, Mario Nonino, Erik D. Reese, Piero Rosati, Craig Sarazin, Keiichi Umetsu. 2014-11-02. Measurements of the Sunyaev-Zel'dovich Effect in MACS J0647.7+7015 and MACS J1206.2-0847 at High Angular Resolution with MUSTANG. https://doi.org/10.1088/0004-637x%2F809%2F2%2F185

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