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Diffuse Radio Emission in the Complex Merging Cluster Abell 2069

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Diffuse Radio Emission in the Complex Merging Cluster Abell 2069 DiffuseDiffuse radioradio emissionemission inin thethe CoronaCorona BorealisBorealis superclustersupercluster fieldfield Alexander Drabent M. Hoeft, M. Brüggen, G. Brunetti, T. W. Shimwell and the LOFAR Surveys KSP Cluster working group 26th October, 2017 The Corona Borealis Supercluster field The Corona Borealis Supercluster field z ~ 0.07 Corona Borealis supercluster The Corona Borealis Supercluster field z ~ 0.11 'Abell 2069'-supercluster Corona Borealis supercluster field A2061 ° 5 A2069 LOFAR HBA @ 153 MHz A2065 beam: 28'' × 24'' r.m.s. noise: 450 μJy/beam Abell 2061-Abell 2067 bridge? (Farnsworth+2013) A2061 A2069 greyscale: Rosat PSPC X-ray red: GBT @ 1.4 GHz A2065 AbellAbell 20612061 steep spectrum radio source at cluster center (van Weeren+2011) (Drabent+ in prep) radio galaxies radio galaxies A2061 ° 5 radio relic A2069 radio relic no radio halo ? embedded sources contours: WSRT @ 346 MHz contours: WSRT @ 1.4 GHz Radio relic: (90 ± 9) mJy (27 ± 1) mJy spectral index of radio relic: -0.9 ± 0.1 AbellAbell 20612061 radio halo found – filaments of radio relic visible (Drabent+ in prep) A2061 radio relic (»-1.5) radio halo with ultra-steep-spectrum source (»-1.9) black contours: LOFAR @ 153 MHz blue contours: WSRT @ 346 MHz colorscale: Chandra 0.5 – 7 keV A2065 Abell 2061 radio halo + embedded ultra-steep spectrum source (Drabent+ in prep) BCG old electron population? black contours: LOFAR @ 153 MHz colorscale: Chandra 0.5 – 7 keV Abell 2065 greyscale: NVSS clipped at 1.35mJy/beam (Farnsworth+2013) blue: Rosat PSPC X-ray red: GBT @ 1.4 GHz A2065 Abell 2065 radio halo structure recovered (Drabent+ in prep.) A2061 A2069 black contours: LOFAR @ 153 MHz colorscale: Chandra 0.5 – 7 keV Abell 2065 radio halo structure recovered cluster galaxies A2061 BCGs LOFAR A2069 black contours: LOFAR @ 153 MHz colorscale: Chandra 0.5 – 7 keV Abell 2069 (Farnsworth+2013) cold front BB (Owers+2009) AA greyscale: NVSS clipped at 1.35mJy/beam blue: Rosat PSPC X-ray red: GBT @ 1.4 GHz Abell 2069: diffuse emission in both components (Drabent+2015) source of uncertain nature (15 ± 2 mJy) radio halo (25 … 39 mJy) contours: WSRT @ 346 MHz colorscale: Chandra 0.5 – 7 keV Abell 2069: diffuse emission is ultra-steep (Drabent+ in prep.) ultra-steep spectrum (»-2.2) low-mass environment BB radio bridge? radio halo (≲-1.4) AA black contours: LOFAR @ 153 MHz green contours: GMRT @ 610 MHz colorscale: Chandra 0.5 – 7 keV Abell 2069B: Too small for a radio halo B 400 kpc (Drabent+ in prep.) Abell 2069B: no powerful AGN present (Drabent+ in prep.) “old” electron population? 0.5 mJy (610 MHz) cluster members LOFAR HBA @ 153 MHz GMRT @ 610 MHz SDSS r-band Abell 2069B: indication for radio – X-ray correlation 3σ rms 3σ rms derive radio emissivity Radio mini-halos are not small radio halos (Murgia+2009) constant emissivity volume-averaged radio emissivity Radio mini-halos: wide span of detection emissivites limit Radio mini-halos are not small radio halos (Murgia+2009) constant emissivity A2069B volume-averaged A2069A radio emissivity A2069B comparable to A2029 detection limit radio mini-halo? Abell 2069B: potential scenario for its origin cold front minor merger or AGN interaction with main cluster (inactive) fossil gas sloshing re-acceleration plasma (cold front) re-distribution diffuse synchrotron emission → Abell 2069 is a two-halo system Diffuse radio emission in the Corona Borealis supercluster field – radio relic more extended at low frequencies – peculiar radio halo with embedded ultra-steep spectrum source – peculiar two-halo system – ultra-steep spectrum „radio mini-halo“ in a low mass environment – radio halo structure recovered for the first time.
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