Please use this identifier to cite or link to this item:
http://hdl.handle.net/2289/4419
Title: | Multi-frequency studies of radio relics in the galaxy clusters A4038, A1664, and A786 |
Authors: | Kale, Ruta Dwarakanath, K.S. |
Keywords: | Galaxies Clusters A4038 A1664 A786 Intracluster medium Radiation mechanism Non-thermal |
Issue Date: | Jan-2012 |
Publisher: | The University of Chicago Press for the American Astronomical Society |
Citation: | Astrophysical Journal, 2012, Vol.744, p1 |
Abstract: | We present a multi-frequency study of radio relics associated with the galaxy clusters A4038, A1664, and A786. Radio images, integrated spectra, spectral index maps, and fits to the integrated spectra in the framework of the adiabatic compression model are presented. Images of the relic in A4038 at 150, 240, and 606 MHz with the Giant Meterwave Radio Telescope have revealed extended ultra-steep spectrum (α ~ -1.8 to -2.7) emission of extent 210 × 80 kpc2. The model of passively evolving radio lobes compressed by a shock fits the integrated spectrum best. The relic with a circular morphology at the outskirts of the cluster A1664 has an integrated spectral index of ~ - 1.10 ± 0.06 and is best fit by the model of radio lobes lurking for ~4 × 107 yr. The relic near A786 has a curved spectrum and is best fit by a model of radio lobes lurking for ~3 × 107 yr. At 4.7 GHz, a compact radio source, possibly the progenitor of the A786 relic, is detected near the center of the radio relic. The A786 radio relic is thus likely a lurking radio galaxy rather than a site of cosmological shock as has been considered in earlier studies. |
Description: | Restricted Access. An open-access version is available at arXiv.org (one of the alternative locations) |
URI: | http://hdl.handle.net/2289/4419 |
ISSN: | 0004-637X 1538-4357 (Online) |
Alternative Location: | http://adsabs.harvard.edu/abs/2012ApJ...744...46K http://arxiv.org/abs/1109.3261 http://dx.doi.org/ 10.1088/0004-637X/744/1/46 |
Copyright: | 2012 American Astronomical Society. |
Appears in Collections: | Research Papers (A&A) |
Files in This Item:
File | Description | Size | Format | |
---|---|---|---|---|
2012_AJ_744_1_46.pdf Restricted Access | Restricted Access | 2.8 MB | Adobe PDF | View/Open Request a copy |
Items in RRI Digital Repository are protected by copyright, with all rights reserved, unless otherwise indicated.