arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1708.01400astro-ph.GAastro-ph.CO
收藏

Abell 2744和ΛCDM中大质量次晕数目差异的解决

Resolution of the apparent discrepancy between the number of massive subhaloes in Abell 2744 and ΛCDM

Tian-Xiang Mao, Jie Wang, Carlos S. Frenk, Liang Gao, Ran Li, Qiao Wang, Xiaoyue Cao, Ming Li

摘要:

Schwinn等人(2017)最近比较了Jauzac等人(2016)在Abell 2744的引力透镜分析中发现的大质量子结构的丰度和分布。Schwinn等人(2017)确定了测量的投影孔径质量与MXXL N体模拟中与subhaloes相关的实际质量。我们已经使用高分辨率的凤凰星系团模拟表明,这样的识别是不正确的:光圈质量占主导地位的质量在身体的集群,恰好是沿着视线投射到subhalo。这种增强的倍数从几倍到100倍以上不等,特别是对于预测的靠近星团中心的半晕。我们在我们的模拟计算光圈质量的subhaloes,并将它们的测量阿贝尔2744。我们发现Abell 2744的数据与ΛCDM的匹配预测非常一致。我们提供了进一步的预测孔径质量函数的subhaloes在理想化的调查与不同的质量检测阈值。

英文摘要:

Schwinn et al. (2017) have recently compared the abundance and distribution of massive substructures identified in a gravitational lensing analysis of Abell 2744 by Jauzac et al. (2016) and N-body simulation and found no cluster in ΛCDM simulation that is similar to Abell 2744. Schwinn et al.(2017) identified the measured projected aperture masses with the actual masses associated with subhaloes in the MXXL N-body simulation. We have used the high resolution Phoenix cluster simulations to show that such an identification is incorrect: the aperture mass is dominated by mass in the body of the cluster that happens to be projected along the line-of-sight to the subhalo. This enhancement varies from factors of a few to factors of more than 100, particularly for subhaloes projected near the centre of the cluster. We calculate aperture masses for subhaloes in our simulation and compare them to the measurements for Abell 2744. We find that the data for Abell 2744 are in excellent agreement with the matched predictions from ΛCDM. We provide further predictions for aperture mass functions of subhaloes in idealized surveys with varying mass detection thresholds.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑