期刊
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
卷 451, 期 4, 页码 4207-4214出版社
OXFORD UNIV PRESS
DOI: 10.1093/mnras/stv1152
关键词
galaxies: clusters: individual: Abell 3376; galaxies: clusters: intracluster medium
资金
- US National Science Foundation [AST-0457585, PHY-0835713, 0847753, AST-0908884]
- Australian Research Council (LIEF) [LE0775621, LE0882938]
- US Air Force Office of Scientific Research [FA9550-0510247]
- Centre for All-sky Astrophysics (an Australian Research Council Centre of Excellence) [CE110001020]
- Smithsonian Astrophysical Observatory
- MIT School of Science
- Raman Research Institute
- Australian National University
- Victoria University of Wellington (New Zealand Ministry of Economic Development) [MED-E1799]
- Victoria University of Wellington (IBM Shared University)
- CSIRO
- National Collaborative Research Infrastructure Strategy, Education Investment Fund
- Australia India Strategic Research Fund
- Astronomy Australia Limited
- NVIDIA at Harvard University
- International Centre for Radio Astronomy Research (ICRAR), a Joint Venture of Curtin University
- University of Western Australia by Western Australian State government
- Division Of Astronomical Sciences
- Direct For Mathematical & Physical Scien [0847753] Funding Source: National Science Foundation
We have carried out multiwavelength observations of the nearby (z = 0.046) rich, merging galaxy cluster Abell 3376 with the Murchison Widefield Array (MWA). As a part of the GaLactic and Extragalactic All-sky MWA Survey, this cluster was observed at 88, 118, 154, 188, and 215 MHz. The known radio relics, towards the eastern and western peripheries of the cluster, were detected at all the frequencies. The relics, with a linear extent of similar to 1 Mpc each, are separated by similar to 2 Mpc. Combining the current observations with those in the literature, we have obtained the spectra of these relics over the frequency range 80-1400 MHz. The spectra follow power laws, with alpha = -1.17 +/- A 0.06 and -1.37 +/- A 0.08 for the west and east relics, respectively (S infinity nu(infinity)). Assuming the break frequency to be near the lower end of the spectrum we estimate the age of the relics to be similar to 0.4 Gyr. No diffuse radio emission from the central regions of the cluster (halo) was detected. The upper limit on the radio power of any possible halo that might be present in the cluster is a factor of 35 lower than that expected from the radio power and X-ray luminosity correlation for cluster haloes. From this we conclude that the cluster halo is very extended (> 500 kpc) and/or most of the radio emission from the halo has decayed. The current limit on the halo radio power is a factor of 10 lower than the existing upper limits with possible implications for models of halo formation.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据