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arXiv 2402.08460astro-ph.CO
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SRG/eROSITA 全天巡天:通过星系团聚类研究追踪大尺度结构

The SRG/eROSITA All-Sky Survey: Tracing the Large-Scale Structure with a clustering study of galaxy clusters

R. Seppi, J. Comparat, V. Ghirardini, C. Garrel, E. Artis, A. G. Sanchez, A. Liu, N. Clerc, E. Bulbul, S. Grandis, M. Kluge, T. H. Reiprich, A. Merloni, X. Zhan… 展开作者

R. Seppi, J. Comparat, V. Ghirardini, C. Garrel, E. Artis, A. G. Sanchez, A. Liu, N. Clerc, E. Bulbul, S. Grandis, M. Kluge, T. H. Reiprich, A. Merloni, X. Zhang, Y. E. Bahar, S. Shreeram, J. Sanders, M. Ramos-Ceja, M. Krumpe

AI总结:

本文利用 eRASS1 星系团样本,首次通过 HOD 与 HAM 模型联合拟合聚类和宇宙学参数,揭示了不同光度星系团的晕占据与偏袒特征,并约束了冷暗物质密度。

摘要:

星系团的空间分布为宇宙中大尺度物质分布提供了可靠的示踪。聚类信号取决于星系团的内禀性质与宇宙学参数。搭载于 Spectrum-Roentgen-Gamma(SRG)上的 eROSITA 发现星系团的能力,使得探测延展 X 射线辐射与暗物质晕之间的关联成为可能。我们的目标是测量投影两点相关函数,以研究第一次 eROSITA 全天巡天(eRASS1)探测到的星系团和星系群对暗物质晕的占据情况。我们构建了五个体积受限样本,探测具有不同红移和 X 射线光度的星系团。我们利用晕占据分布(HOD)模型和晕丰度匹配(HAM)模型解释相关函数。我们同时拟合了一个包含 6493 个星系团、纯度大于 96% 的流量受限样本的宇宙学参数和晕偏袒。结果:我们获得了 eRASS1 星系团晕占据的详细图像。低红移处的较暗群体(S0:LX = 4.63E43 erg/s,0.1 < z < 0.2)相对于暗物质的偏袒最小,b = 2.95 ± 0.21。延伸到较高红移的最亮星系团(S4:LX = 1.77E44 erg/s,0.1 < z < 0.6)表现出更高的偏袒 b = 4.34 ± 0.62。卫星星系群很少见,S0(S4)样本的卫星比例小于 14.9%(8.1%)。我们将 HOD 预测与 HAM 程序相结合,以一种新的方式约束 LX 与质量之间的标度关系,并发现弥散为 0.36。我们得到了物理冷暗物质密度 0.12+0.03-0.02 和平均晕偏袒 b = 3.63+1.02-0.85 的宇宙学约束。我们首次采用 HOD 方法对星系团聚类进行建模,为未来将 eROSITA 与 4MOST、SDSS、Euclid、Rubin 和 DESI 相结合以揭示宇宙中星系团分布的研究铺平了道路。

英文摘要:

The spatial distribution of galaxy clusters provides a reliable tracer of the large-scale distribution of matter in the Universe. The clustering signal depends on intrinsic cluster properties and cosmological parameters. The ability of eROSITA onboard Spectrum-Roentgen-Gamma (SRG) to discover galaxy clusters allows probing the association of extended X-ray emission to dark matter haloes. We aim to measure the projected two-point correlation function to study the occupation of dark matter halos by clusters and groups detected by the first eROSITA all-sky survey (eRASS1). We create five volume-limited samples probing clusters with different redshift and X-ray luminosity. We interpret the correlation function with halo occupation distribution (HOD) and halo abundance matching (HAM) models. We simultaneously fit cosmological parameters and halo bias of a flux-limited sample of 6493 clusters with purity > 96%. Results. We obtain a detailed view of the halo occupation for eRASS1 clusters. The fainter population at low redshift (S0: LX = 4.63E43 erg/s, 0.1 < z < 0.2) is the least biased compared to dark matter, with b = 2.95 $\pm$ 0.21. The brightest clusters up to higher redshift (S4: LX = 1.77E44 erg/s , 0.1 < z < 0.6) exhibit a higher bias b = 4.34 $\pm$ 0.62. Satellite groups are rare, with a satellite fraction < 14.9% (8.1) for the S0 (S4) sample. We combine the HOD prediction with a HAM procedure to constrain the scaling relation between LX and mass in a new way and find a scatter of 0.36. We obtain cosmological constraints for the physical cold dark matter density 0.12+0.03-0.02 and an average halo bias b = 3.63+1.02-0.85. We model the clustering of galaxy clusters with a HOD approach for the first time, paving the way for future studies combining eROSITA with 4MOST, SDSS, Euclid, Rubin, and DESI to unravel the cluster distribution in the Universe.

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。

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