تقرير
Radio fossils, relics, and haloes in Abell 3266: cluster archaeology with ASKAP-EMU and the ATCA
| العنوان: | Radio fossils, relics, and haloes in Abell 3266: cluster archaeology with ASKAP-EMU and the ATCA |
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| المؤلفون: | Riseley, C. J., Bonnassieux, E., Vernstrom, T., Galvin, T. J., Chokshi, A., Botteon, A., Rajpurohit, K., Duchesne, S. W., Bonafede, A., Rudnick, L., Hoeft, M., Quici, B., Eckert, D., Brienza, M., Tasse, C., Carretti, E., Collier, J. D., Diego, J. M., Di Mascolo, L., Hopkins, A. M., Johnston-Hollitt, M., Keel, R. R., Koribalski, B. S., Reiprich, T. H. |
| سنة النشر: | 2022 |
| المجموعة: | Astrophysics |
| مصطلحات موضوعية: | Astrophysics - Astrophysics of Galaxies, Astrophysics - Cosmology and Nongalactic Astrophysics |
| الوصف: | Abell 3266 is a massive and complex merging galaxy cluster that exhibits significant substructure. We present new, highly sensitive radio continuum observations of Abell 3266 performed with the Australian Square Kilometre Array Pathfinder (0.8$-$1.1 GHz) and the Australia Telescope Compact Array (1.1$-$3.1 GHz). These deep observations provide new insights into recently-reported diffuse non-thermal phenomena associated with the intracluster medium, including a 'wrong-way' relic, a fossil plasma source, and an as-yet unclassified central diffuse ridge, which we reveal comprises the brightest part of a large-scale radio halo detected here for the first time. The 'wrong-way' relic is highly atypical of its kind: it exhibits many classical signatures of a shock-related radio relic, while at the same time exhibiting strong spectral steepening. While radio relics are generally consistent with a quasi-stationary shock scenario, the 'wrong-way' relic is not. We study the spectral properties of the fossil plasma source; it exhibits an ultra-steep and highly curved radio spectrum, indicating an extremely aged electron population. The larger-scale radio halo fills much of the cluster centre, and presents a strong connection between the thermal and non-thermal components of the intracluster medium, along with evidence of substructure. Whether the central diffuse ridge is simply a brighter component of the halo, or a mini-halo, remains an open question. Finally, we study the morphological and spectral properties of the multiple complex radio galaxies in this cluster in unprecedented detail, tracing their evolutionary history. Comment: Main article contains 26 pages, 15 figures, 6 tables. Supplementary material contains figures illustrating the improvement gain by applying third-generation calibration and imaging techniques to ATCA and ASKAP data. Manuscript published Open Access in MNRAS on August 1st |
| نوع الوثيقة: | Working Paper |
| DOI: | 10.1093/mnras/stac1771 |
| URL الوصول: | http://arxiv.org/abs/2208.00395 |
| رقم الأكسشن: | edsarx.2208.00395 |
| قاعدة البيانات: | arXiv |
| DOI: | 10.1093/mnras/stac1771 |
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