Letter to the Editor

Discovery of the correspondence between intra-cluster radio emission and a high pressure region detected through the Sunyaev-Zel’dovich effect

¹ Université de Nice Sophia Antipolis, CNRS, Observatoire de la Côte d’Azur, Laboratoire Cassiopée, Nice, France
e-mail: chiara.ferrari@oca.eu
² National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903-2475, USA
³ Radboud University Nijmegen, Heijendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
⁴ INAF – Osservatorio Astronomico di Cagliari, Strada 54, Loc. Poggio dei Pini, 09012 Capoterra ( Ca), Italy
⁵ Dipartimento di Fisica, Università degli Studi di Roma “Tor Vergata”, via della Ricerca Scientifica 1, 00133 Roma, Italy
⁶ Master student of the “AstroMundus” Erasmus Mundus Masters Course  
⁷ Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138, USA
⁸ ASTRON, PO Box 2, 7990 AA Dwingeloo, The Netherlands
⁹ Astronomical Institute Anton Pannekoek, University of Amsterdam, Amsterdam, The Netherlands
¹⁰ University of Pennsylvania, 209 S. 33rd St., Philadelphia, PA 19104, USA
¹¹ NASA Einstein Postdoctoral Fellow  
¹² School of Physics and Astronomy, University of Southampton, Southampton, SO17 1BJ, UK

Received: 29 July 2011
Accepted: 6 October 2011

Abstract

We analyzed new 237 MHz and 614 MHz GMRT data of the most X-ray luminous galaxy cluster, RX J1347-1145. Our radio results are compared with the MUSTANG 90 GHz Sunyaev-Zel’dovich effect map and with re-processed Chandra and XMM-Newton archival data of this cluster. We point out for the first time in an unambiguous way the correspondence between a radio excess in a diffuse intra-cluster radio source and a hot region detected through both Sunyaev-Zel’dovich effect and X-ray observations. Our result indicates that electron re-acceleration in the excess emission of the radio mini-halo at the center of RX J1347-1145 is most likely related to a shock front propagating into the intra-cluster medium.