A Massive Cluster at z = 0.288 Caught in the Process of Formation: The Case of Abell 959
The largest galaxy clusters are observed still to be forming through major cluster-cluster mergers, often showing observational signatures such as radio relics and giant radio haloes. Using LOFAR Two-meter Sky Survey data, we present new detections of both a radio halo (with a spectral index of...
| Main Authors: | , , , , , , , , , , , |
|---|---|
| Format: | Journal Article |
| Subjects: | |
| Online Access: | http://hdl.handle.net/20.500.11937/76030 |
| _version_ | 1848763608381521920 |
|---|---|
| author | Bîrzan, L. Rafferty, D.A. Cassano, R. Brunetti, G. Weeren, RJ van Brüggen, M. Intema, Huib Gasperin, F de Andrade-Santos, F. Botteon, A. Röttgering, H.J.A. Shimwell, T.W. |
| author_facet | Bîrzan, L. Rafferty, D.A. Cassano, R. Brunetti, G. Weeren, RJ van Brüggen, M. Intema, Huib Gasperin, F de Andrade-Santos, F. Botteon, A. Röttgering, H.J.A. Shimwell, T.W. |
| author_sort | Bîrzan, L. |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | The largest galaxy clusters are observed still to be forming through major
cluster-cluster mergers, often showing observational signatures such as radio
relics and giant radio haloes. Using LOFAR Two-meter Sky Survey data, we
present new detections of both a radio halo (with a spectral index of
$\alpha_{143}^{1400}=1.48^{+0.06}_{-0.23}$) and a likely radio relic in Abell
959, a massive cluster at a redshift of z=0.288. Using a sample of clusters
with giant radio haloes from the literature (80 in total), we show that the
radio halo in A959 lies reasonably well on the scaling relations between the
thermal and non-thermal power of the system. Additionally, we find evidence
that steep-spectrum haloes tend to reside in clusters with high X-ray
luminosities relative to those expected from cluster LM scaling relations,
indicating that such systems may preferentially lie at an earlier stage of the
merger, consistent with the theory that some steep-spectrum haloes result from
low-turbulence mergers. Lastly, we find that halo systems containing radio
relics tend to lie at lower X-ray luminosities, relative to those expected from
cluster LM scaling relations, for a given halo radio power than those without
relics, suggesting that the presence of relics indicates a later stage of the
merger, in line with simulations. |
| first_indexed | 2025-11-14T11:06:10Z |
| format | Journal Article |
| id | curtin-20.500.11937-76030 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| last_indexed | 2025-11-14T11:06:10Z |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-760302019-07-23T01:30:47Z A Massive Cluster at z = 0.288 Caught in the Process of Formation: The Case of Abell 959 Bîrzan, L. Rafferty, D.A. Cassano, R. Brunetti, G. Weeren, RJ van Brüggen, M. Intema, Huib Gasperin, F de Andrade-Santos, F. Botteon, A. Röttgering, H.J.A. Shimwell, T.W. astro-ph.CO astro-ph.CO The largest galaxy clusters are observed still to be forming through major cluster-cluster mergers, often showing observational signatures such as radio relics and giant radio haloes. Using LOFAR Two-meter Sky Survey data, we present new detections of both a radio halo (with a spectral index of $\alpha_{143}^{1400}=1.48^{+0.06}_{-0.23}$) and a likely radio relic in Abell 959, a massive cluster at a redshift of z=0.288. Using a sample of clusters with giant radio haloes from the literature (80 in total), we show that the radio halo in A959 lies reasonably well on the scaling relations between the thermal and non-thermal power of the system. Additionally, we find evidence that steep-spectrum haloes tend to reside in clusters with high X-ray luminosities relative to those expected from cluster LM scaling relations, indicating that such systems may preferentially lie at an earlier stage of the merger, consistent with the theory that some steep-spectrum haloes result from low-turbulence mergers. Lastly, we find that halo systems containing radio relics tend to lie at lower X-ray luminosities, relative to those expected from cluster LM scaling relations, for a given halo radio power than those without relics, suggesting that the presence of relics indicates a later stage of the merger, in line with simulations. Journal Article http://hdl.handle.net/20.500.11937/76030 10.1093/mnras/stz1456 fulltext |
| spellingShingle | astro-ph.CO astro-ph.CO Bîrzan, L. Rafferty, D.A. Cassano, R. Brunetti, G. Weeren, RJ van Brüggen, M. Intema, Huib Gasperin, F de Andrade-Santos, F. Botteon, A. Röttgering, H.J.A. Shimwell, T.W. A Massive Cluster at z = 0.288 Caught in the Process of Formation: The Case of Abell 959 |
| title | A Massive Cluster at z = 0.288 Caught in the Process of Formation: The Case of Abell 959 |
| title_full | A Massive Cluster at z = 0.288 Caught in the Process of Formation: The Case of Abell 959 |
| title_fullStr | A Massive Cluster at z = 0.288 Caught in the Process of Formation: The Case of Abell 959 |
| title_full_unstemmed | A Massive Cluster at z = 0.288 Caught in the Process of Formation: The Case of Abell 959 |
| title_short | A Massive Cluster at z = 0.288 Caught in the Process of Formation: The Case of Abell 959 |
| title_sort | massive cluster at z = 0.288 caught in the process of formation: the case of abell 959 |
| topic | astro-ph.CO astro-ph.CO |
| url | http://hdl.handle.net/20.500.11937/76030 |