2014/04/29 by Andra Stroe, Stroe, Andra, Reinout J. van Weeren +17
Physics and Astronomy · #Astrophysics of Galaxies (astro-ph.GA) #Cosmology and Nongalactic Astrophysics (astro-ph.CO) #FOS: Physical sciences #astro-ph.CO #astro-ph.GA
paper · pdf · doi:10.48550/arxiv.1404.7285
4 pages, 2 figures, to appear in the proceedings of the conference `The Metre Wavelength Sky: Celebrating 50 years of Radio Astronomy at TIFR'
arxiv created 2014/04/29 · arxiv updated 2014/04/30
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 Hα emitters by a factor of 10, possibly caused by interactions of the galaxies with the shock wave.