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arXiv · 1404.7285

Spectral and morphological signatures of cluster merger shocks: CIZA J2242.8+5301

Andra Stroe·Reinout J. van Weeren·David Sobral·Clare Rumsey·Huib T. Intema·Huub J. A. Röttgering·Jeremy J. Harwood·Richard Saunders·Marcus Brüggen·Matthias Hoeft
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Abstract

The CIZA J2242.8+5301 cluster hosts an extraordinary, narrow, Mpc-wide, diffuse patch of radio emission tracing travelling shock waves, called a relic. We perform a multi-wavelength of observations of the cluster. We discover radio spectral steepening and increasing spectral curvature in the shock downstream area, indicative of emission produced by spectrally-aged electrons, following a JP ageing model. The curved integrated spectrum towards $16$ GHz challenges the favoured relic formation model. Further, we find a boosting the number density of H$α$ emitters by a factor of $10$, possibly caused by interactions of the galaxies with the shock wave.

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Andra Stroe, Reinout J. van Weeren, David Sobral, Clare Rumsey, Huib T. Intema, Huub J. A. Röttgering, Jeremy J. Harwood, Richard Saunders, Marcus Brüggen, Matthias Hoeft. 2014-04-29. Spectral and morphological signatures of cluster merger shocks: CIZA J2242.8+5301. https://arxiv.org/abs/1404.7285

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