A giant radio halo in a low-mass SZ-selected galaxy cluster: ACT-CL J0256.5+0006
dc.contributor.author | Knowles, K. | |
dc.contributor.author | Intema, Hubertus | |
dc.contributor.author | Baker, A. | |
dc.contributor.author | Bharadwaj, V. | |
dc.contributor.author | Bond, J. | |
dc.contributor.author | Cress, C. | |
dc.contributor.author | Gupta, N. | |
dc.contributor.author | Hajian, A. | |
dc.contributor.author | Hilton, M. | |
dc.contributor.author | Hincks, A. | |
dc.contributor.author | Hlozek, R. | |
dc.contributor.author | Hughes, J. | |
dc.contributor.author | Lindner, R. | |
dc.contributor.author | Marriage, T. | |
dc.contributor.author | Menanteau, F. | |
dc.contributor.author | Moodley, K. | |
dc.contributor.author | Niemack, M. | |
dc.contributor.author | Reese, E. | |
dc.contributor.author | Sievers, J. | |
dc.contributor.author | Sifón, C. | |
dc.contributor.author | Srianand, R. | |
dc.contributor.author | Wollack, E. | |
dc.date.accessioned | 2019-02-19T04:16:55Z | |
dc.date.available | 2019-02-19T04:16:55Z | |
dc.date.created | 2019-02-19T03:58:35Z | |
dc.date.issued | 2016 | |
dc.identifier.citation | Knowles, K. and Intema, H. and Baker, A. and Bharadwaj, V. and Bond, J. and Cress, C. and Gupta, N. et al. 2016. A giant radio halo in a low-mass SZ-selected galaxy cluster: ACT-CL J0256.5+0006. Monthly Notices of the Royal Astronomical Society. 459 (4): pp. 4240-4258. | |
dc.identifier.uri | http://hdl.handle.net/20.500.11937/74425 | |
dc.identifier.doi | 10.1093/mnras/stw795 | |
dc.description.abstract |
We present the detection of a giant radio halo (GRH) in the Sunyaev-Zel'dovich (SZ)-selected merging galaxy cluster ACT-CL J0256.5+0006 (z = 0.363), observed with the Giant Metrewave Radio Telescope at 325 and 610 MHz. We find this cluster to host a faint (S610= 5.6 ± 1.4 mJy) radio halo with an angular extent of 2.6 arcmin, corresponding to 0.8 Mpc at the cluster redshift, qualifying it as a GRH. J0256 is one of the lowest mass systems, M500, SZ= (5.0 ± 1.2) × 1014M?, found to host a GRH. We measure the GRH at lower significance at 325 MHz (S325= 10.3 ± 5.3 mJy), obtaining a spectral index measurement of a325610= 1.0-0.9+0.7. This result is consistent with the mean spectral index of the population of typical radio haloes, a = 1.2 ± 0.2. Adopting the latter value, we determine a 1.4 GHz radio power of P1.4 GHz= (1.0 ± 0.3) × 1024W Hz-1, placing this cluster within the scatter of known scaling relations. Various lines of evidence, including the intracluster medium morphology, suggest that ACT-CL J0256.5+0006 is composed of two subclusters. We determine a merger mass ratio of 7:4, and a line-of-sight velocity difference of v? = 1880 ± 210 km s-1. We construct a simple merger model to infer relevant time-scales in the merger. From its location on the P1.4 GHz-LXscaling relation, we infer that we observe ACT-CL J0256.5+0006 just before first core crossing. | |
dc.publisher | Oxford University Press | |
dc.title | A giant radio halo in a low-mass SZ-selected galaxy cluster: ACT-CL J0256.5+0006 | |
dc.type | Journal Article | |
dcterms.source.volume | 459 | |
dcterms.source.number | 4 | |
dcterms.source.startPage | 4240 | |
dcterms.source.endPage | 4258 | |
dcterms.source.issn | 0035-8711 | |
dcterms.source.title | Monthly Notices of the Royal Astronomical Society | |
curtin.note |
This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society ©: 2016 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved. | |
curtin.accessStatus | Open access |