Giant Ringlike Radio Structures Around Galaxy Cluster Abell 3376
Abstract
In the current paradigm of cold dark matter cosmology, large-scale structures are assembling through hierarchical clustering of matter. In this process, an important role is played by megaparsec (Mpc)–scale cosmic shock waves, arising in gravity-driven supersonic flows of intergalactic matter onto dark matter–dominated collapsing structures such as pancakes, filaments, and clusters of galaxies. Here, we report Very Large Array telescope observations of giant (∼2 Mpc by 1.6 Mpc), ring-shaped nonthermal radio-emitting structures, found at the outskirts of the rich cluster of galaxies Abell 3376. These structures may trace the elusive shock waves of cosmological large-scale matter flows, which are energetic enough to power them. These radio sources may also be the acceleration sites where magnetic shocks are possibly boosting cosmic-ray particles with energies of up to 1018 to 1019 electron volts.
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Supplementary Material
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F.D. acknowledges support from Centre National d'Etudes Spatiales and Programme National Cosmologie, CNRS/Institut National des Sciences de l'Univers. G.B.L.N. acknowledges support from Conselho Nacional de Desenvolvimento Científico e Technológico, Coordenação de Aperfeiçoamento de Pessoal de Nível Superior/Cofecub Brazilian-French collaboration, and Fundação de Amparo à Pesquisa de São Paulo through the Thematic Project 01/07342-7. S.P. acknowledges the Deutsche Forschungsgemeinschaft (DFG), Research Training Groups (RTG) 1147 for financial support and specially thanks The Inter-University Centre for Astronomy and Astrophysics for support. The National Radio Astronomy Observatory is a facility of the NSF operated under cooperative agreement by Associated Universities, Inc. The x-ray data are based on observations obtained with XMM-Newton, a European Space Agency (ESA) science mission with instruments and contributions directly funded by ESA Member States and NASA.
Information & Authors
Information
Published In
Science
Volume 314 • Issue 5800 • 3 November 2006
Pages: 791 - 794
History
Received: 12 June 2006
Accepted: 6 October 2006
Copyright
American Association for the Advancement of Science.
