A radio ridge connecting two galaxy clusters in a filament of the cosmic web

F. Govoni , E. Orrù (1) , A. Bonafede (2) , M. Iacobelli (3) , R. Paladino (4) , F. Vazza , M. Murgia , V. Vacca , G. Giovannini (5) , L. Feretti , F. Loi , G. Bernardi (6) , C. Ferrari (7) , R. Pizzo (1) , C. Gheller , S. Manti , M. Brüggen (2) , G. Brunetti (8) , R. Cassano (8) , F. de Gasperin (9) , T. Ensslin , M. Hoeft , C. Horellou , H. Junklewitz , H. Röttgering , A. Scaife , T. Shimwell , R. van Weeren , M. Wise

1 ASTRON - Netherlands Institute for Radio Astronomy
2 Jacobs University = Constructor University [Bremen]
3 Leiden Observatory [Leiden]
4 UNIBO - Alma Mater Studiorum Università di Bologna = University of Bologna
5 SGDG - Services généraux
6 LPNHE (UMR_7585) - Laboratoire de Physique Nucléaire et de Hautes Énergies
7 LAGRANGE - Joseph Louis LAGRANGE
8 IRA - Istituto di Radioastronomia [Bologna]
9 Hamburger Sternwarte/Hamburg Observatory

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. Govoni et al. used the Low-Frequency Array (LOFAR) radio telescope to observe a ridge of radio-emitting plasma extending between two galaxy clusters that are approaching a merger. The results imply that intergalactic magnetic fields connect the two clusters and challenge theories of particle acceleration in the intergalactic medium. Science , this issue p. 981

Domaines: Cosmologie et astrophysique extra-galactique [astro-ph.CO]

F. Govoni, E. Orrù, A. Bonafede, M. Iacobelli, R. Paladino, et al.. A radio ridge connecting two galaxy clusters in a filament of the cosmic web. Science, 2019, 364 (6444), pp.981-984. ⟨10.1126/science.aat7500⟩. ⟨hal-03648674⟩