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تسجيل مستخدم جديدMeasurements of the Sunyaev-Zeldovich Effect in MACS J0647.7+7015 and MACS J1206.2-0847 at High Angular Resolution with MUSTANG
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We present high resolution (9$^{prime prime}$) imaging of the Sunyaev-Zeldovich 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 $gamma= 0.9$ fits the MUSTANG image with $chi^{2}_{red}=1.005$ and probability to exceed (PTE) = 0.34. For MACS J1206.2-0847, we find $gamma=0.7$, $chi^{2}_{red}=0.993$, and PTE = 0.70. In addition, we find a significant ($>$3-$sigma$) residual SZE feature in MACS J1206.2-0847 coincident with a group of galaxies identified in VLT data and filamentary structure found in a weak-lensing mass reconstruction. We suggest the detected sub-structure may be the SZE decrement from a low mass foreground group or an infalling group. GMRT measurements at 610 MHz reveal diffuse extended radio emission to the west, which we posit is either an AGN-driven radio lobe, a bubble expanding away from disturbed gas associated with the SZE signal, or a bubble detached and perhaps re-accelerated by sloshing within the cluster. Using the spectroscopic redshifts available, we find evidence for a foreground ($z=0.423$) or infalling group, coincident with the residual SZE feature.
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