VAN WEEREN , R.

We present the first wide area (19 deg2), deep (≈ 120–150 μJy beam−1), high resolution (5.6× 7.4 arcsec) LOFAR High Band Antenna image of the Bo ̈otes field made at 130-169 MHz. This image is at least an order of magnitude deeper and 3 − 5 times higher in angular resolution than previously achieved for this field at low frequencies. The...

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A radio ridge between two galaxy clusters Galaxy clusters contain dozens or hundreds of galaxies, vast quantities of hot gas, and large amounts of dark matter. The gas can emit at radio wavelengths if it contains electrons at relativistic speeds, which can be injected by active galaxies or accelerated during a merger between two clusters....

With Low-Frequency Array (LOFAR) observations, we have discovered a diverse assembly of steep spectrum emission that is apparently associated with the intracluster medium (ICM) of the merging galaxy cluster Abell 2034. Such a rich variety of complex emission associated with the ICM has been observed in few other clusters. This not only...

International audience

The Advanced Telescope for High Energy Astrophysics (Athena) is the X-ray observatory large mission selected by the European Space Agency (ESA), within its Cosmic Vision 2015-2025 programme, to address the "Hot and Energetic Universe" scientific theme (Nandra et al. 2013), and it is provisionally due for launch in the early 2030s. The Square...