Radial metal abundance profiles in the intra-cluster medium of cool-core galaxy clusters, groups, and ellipticals
Radial metal abundance profiles in the intra-cluster medium of cool-core galaxy clusters, groups, and ellipticals
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DOI：
10.1051/0004-6361/201630075
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发表时间：
2017-03
影响因子：
6.5
通讯作者：
F. Mernier;J. Plaa;J. Kaastra;Yu-ying Zhang;H. Akamatsu;L. Gu;P. Kosec;J. Mao;C. Pinto;T. Reiprich;J. Sanders;A. Simionescu;N. Werner
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文献类型：
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作者：
F. Mernier;J. Plaa;J. Kaastra;Yu-ying Zhang;H. Akamatsu;L. Gu;P. Kosec;J. Mao;C. Pinto;T. Reiprich;J. Sanders;A. Simionescu;N. Werner
热的星系团内介质（ICM）渗透到星系团和星系群中并不是原始的，因为自从星星形成的主要时期（z近似或等于2-3）以来，它一直被Ia型（SNIa）和核心坍缩（SNcc）超新星中合成的金属所富集。团簇/组富集的历史和机制负责释放和混合的金属可以探测通过径向分布的SNIa和SNCC产品内ICM。在本文中，我们使用深XMM-牛顿/EPIC观测样本的44个附近的冷核星系团，集团和椭圆（CHEERS）约束平均径向O，Mg，Si，S，Ar，Ca，Fe和Ni丰度分布。所有这些元素的径向分布，平均在一个大样本的第一次，代表了目前最好的约束配置文件。特别注意的是致力于一个适当的建模的EPIC光谱成分，以及其他系统的不确定性，可能会影响我们的结果。我们发现整体减少的Fe丰度与半径类似的0.9 r（500）和类似的0.6 r（500）的集群和团体，分别与最近的流体动力学模拟的预测。所有其他元素（X）的平均径向分布也在中心达到峰值，并且当重新缩放到它们的平均中心X/Fe比时，很好地遵循Fe分布，至少类似于0.5 r（500）。正如最近的模拟预测，我们发现，SNIa（SNCC）的总ICM富集的相对贡献是一致的，在所有半径是均匀的，无论是集群和集团使用两套SNIa和SNCC产量模型，再现的X/Fe丰度模式的核心井。除了暗示中心金属峰在SNIa和SNcc之间是平衡的之外，我们的结果还表明，富集的SNIa和SNcc产物必须具有相同的起源，并且SNIa和SNcc爆炸的大部分之间的延迟必须短于扩散出金属所需的时间尺度。最后，我们报告了一个明显的丰度下降，在非常核心的14个系统（类似于32%的样本）。这些下降的可能来源进行了讨论。
The hot intra-cluster medium (ICM) permeating galaxy clusters and groups is not pristine, as it has been continuously enriched by metals synthesised in Type Ia (SNIa) and core-collapse (SNcc) supernovae since the major epoch of star formation (z similar or equal to 2-3). The cluster/group enrichment history and mechanisms responsible for releasing and mixing the metals can be probed via the radial distribution of SNIa and SNcc products within the ICM. In this paper, we use deep XMM-Newton/EPIC observations from a sample of 44 nearby cool-core galaxy clusters, groups, and ellipticals (CHEERS) to constrain the average radial O, Mg, Si, S, Ar, Ca, Fe, and Ni abundance profiles. The radial distributions of all these elements, averaged over a large sample for the first time, represent the best constrained profiles available currently. Specific attention is devoted to a proper modelling of the EPIC spectral components, and to other systematic uncertainties that may affect our results. We find an overall decrease of the Fe abundance with radius out to similar to 0.9 r(500) and similar to 0.6 r(500) for clusters and groups, respectively, in good agreement with predictions from the most recent hydrodynamical simulations. The average radial profiles of all the other elements (X) are also centrally peaked and, when rescaled to their average central X/Fe ratios, follow well the Fe profile out to at least similar to 0.5 r(500). As predicted by recent simulations, we find that the relative contribution of SNIa (SNcc) to the total ICM enrichment is consistent with being uniform at all radii, both for clusters and groups using two sets of SNIa and SNcc yield models that reproduce the X/Fe abundance pattern in the core well. In addition to implying that the central metal peak is balanced between SNIa and SNcc, our results suggest that the enriching SNIa and SNcc products must share the same origin and that the delay between the bulk of the SNIa and SNcc explosions must be shorter than the timescale necessary to diffuse out the metals. Finally, we report an apparent abundance drop in the very core of 14 systems (similar to 32% of the sample). Possible origins of these drops are discussed.