2007/12/11 by C. M. Hubert Chen, D. E. Harris, Fiona A. Harrison +1 · 2 citations
Physics and Astronomy · #Astrophysical Phenomena and Observations #Astrophysics and Cosmic Phenomena #Galaxies: Formation, Evolution, Phenomena #astro-ph
paper · pdf · doi:10.1111/j.1365-2966.2007.12633.x
published as MNRAS 383 (3), 1259-1268, 1/2008 · 11 pages, 5 figures. Accepted by MNRAS
openalex publication_date 2007/12/11 · arxiv created 2008/01/01 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We observed two relic radio sources, 0917+75 and 1401−33, with the XMM–Newton X-ray observatory. We did not detect any X-ray emission, thermal or non-thermal, in excess of the local background level from either target. This imposes new upper limits on the X-ray flux due to inverse Compton scattering of photons from the cosmic microwave background by relativistic electrons in the relic sources, and new lower limits on the magnetic field strength from the relative strength of the radio and X-ray emission. The combination of radio and X-ray observations provides a measure of the magnetic field independent of equipartition or minimum energy assumptions. Due to increasing sensitivity of radio observations, the known population of cluster relics has been growing; however, studies of non-thermal X-ray emission from relics remain scarce. Our study adds to the small sample of relics studied in X-rays. In both relics, our field strength lower limits are slightly larger than estimates of the equipartition magnetic field.