The XXL Survey L. Active galactic nucleus contamination in galaxy clusters: Detection and cosmological impact
The XXL Survey L. Active galactic nucleus contamination in galaxy clusters: Detection and cosmological impact
复制标题
XXL 调查 L. 星系团中活跃的星系核污染：检测和宇宙学影响
DOI：
10.1051/0004-6361/202244898
复制
发表时间：
2023
影响因子：
6.5
通讯作者：
Bhargava S
中科院分区：
文献类型：
--
作者：
Bhargava S
星系团的背景X射线观测受到活动星系核（AGN）存在的影响，其方式难以量化，在XXL巡天探测范围内，我们探测和测量了被中心活动星系核污染的星系团，并对这类系统在X-射线中的宇宙学影响进行了系统的评估。射线集群samples.MethodsWe介绍了一个新的自动化类活动星系核污染（AC）集群中的XXL源检测管道。这些系统中的大多数被当前的X射线簇检测方法遗漏。AC的选择也是有效的，在区分活动星系核和冷核的存在，使用补充的光学和红外information.ResultsWe提出了33个AC对象，包括25个集群的红移范围内，0.14 ≤z≤ 1.03，和其他8个源显着峰值中心配置文件的基础上X射线观测。 其中六个是新确认的集群。我们计算了XXL调查的遗漏分数，这被定义为由于其中心峰值X射线轮廓而未被检测到的真正集群的分数。我们报告了7个大于0.6的未检测到的AC团簇，在X射线团簇检测效率显著下降的范围内。 对于50平方度的XXL区域，遗漏分数估计为5%。宇宙学估计从错过集群的影响是可以忽略不计的XXL，但它产生的张力与基准宇宙学时，考虑较大的调查areas.ConclusionsThis工作演示了第一次系统的尝试，以量化错过集群的百分比在X射线调查的结果，中央活动星系核污染。展望像eROSITA和Athena这样的调查，更大的区域和更高的灵敏度将显着增强星团探测，因此，描述活动星系核污染的鲁棒方法对于精确的星团宇宙学至关重要，特别是在redshiftz> 1制度中。
ContextX-ray observations of galaxy clusters are impacted by the presence of active galactic nuclei (AGNs) in a manner that is challenging to quantify, leading to biases in the detection and measurement of cluster properties for both astrophysics and cosmological applications.AimsWe detect and characterise clusters contaminated by central AGNs within the XXL survey footprint and provide a systematic assessment of the cosmological impact of such systems in X-ray cluster samples.MethodsWe introduce a new automated class for AGN-contaminated (AC) clusters in the XXL source detection pipeline. The majority of these systems are otherwise missed by current X-ray cluster-detection methods. The AC selection is also effective in distinguishing AGN and cool-core presence using supplementary optical and infrared information.ResultsWe present 33 AC objects, including 25 clusters in the redshift range, 0.14 ≤z≤ 1.03, and eight other sources with significantly peaked central profiles based on X-ray observations. Six of these are new confirmed clusters. We computed the missed fraction of the XXL survey, which is defined as the fraction of genuine clusters that are undetected due to their centrally peaked X-ray profiles. We report seven undetected AC clusters abovez> 0.6, in the range where X-ray cluster detection efficiency drops significantly. The missed fraction is estimated to be at the level of 5% for the 50 square-degree XXL area. The impact on cosmological estimates from missed clusters is negligible for XXL, but it produces a tension of ∼3σwith the fiducial cosmology when considering larger survey areas.ConclusionsThis work demonstrates the first systematic attempt to quantify the percentage of missed clusters in X-ray surveys as a result of central AGN contamination. Looking towards surveys such as eROSITA and Athena, larger areas and increased sensitivity will significantly enhance cluster detection, and therefore robust methods for characterising AGN contamination will be crucial for precise cluster cosmology, particularly in the redshiftz> 1 regime.