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

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 shoc...

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Bibliographic Details
Main Authors: Stroe, Andra, Weeren, Reinout J van, Sobral, David, Rumsey, Clare, Intema, Huib, Röttgering, Huub JA, Harwood, Jeremy J, Saunders, Richard, Brüggen, Marcus, Hoeft, Matthias
Format: Journal Article
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Online Access:https://astron-soc.in/bulletin/asics_vol013/
http://hdl.handle.net/20.500.11937/76025
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Summary: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$\alpha$ emitters by a factor of $10$, possibly caused by interactions of the galaxies with the shock wave.