The completed SDSS-IV extended Baryon Oscillation Spectroscopic Survey: measurement of the growth rate of structure from the small-scale clustering of the luminous red galaxy sample
The completed SDSS-IV extended Baryon Oscillation Spectroscopic Survey: measurement of the growth rate of structure from the small-scale clustering of the luminous red galaxy sample
复制标题
已完成的SDSS-IV扩展重子振荡光谱巡天：测量发光红色星系样本小规模聚类的结构增长率
DOI：
10.1093/mnras/stac1923
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发表时间：
2022
影响因子：
4.8
通讯作者：
Gil-Marín, Héctor
中科院分区：
文献类型：
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作者：
Chapman, Michael J.;Mohammad, Faizan G.;Zhai, Zhongxu;Percival, Will J.;Tinker, Jeremy L.;Bautista, Julian E.;Brownstein, Joel R.;Burtin, Etienne;Dawson, Kyle S.;Gil-Marín, Héctor
我们测量的数据发布16扩展重子振荡光谱调查明亮的红色星系样本的小规模聚类，校正纤维碰撞使用成对逆概率权重，这给无偏的聚类测量所有尺度。我们用基于aemulus宇宙学模拟器的模型拟合了分离范围内的四极矩和投影相关函数，以测量宇宙结构的增长率，参数化为f σ8。我们获得了σ8（z= 0.737）= 0.408 ± 0.038的测量值，比2018年普朗克数据对平坦ΛCDM模型的预期值低1.4σ，与最近的弱透镜测量结果更一致。达到的精度水平是1.7倍，优于仅使用相同样品的大尺度模式进行的标准测量。我们还使用aemulus宇宙学模拟器模拟的全范围尺度来拟合数据，并发现在Planck + ΛCDM模型中，由非线性尺度上的失配驱动的晕速度场的振幅中存在4.5σ的张力。这可能不是宇宙学的起源，可能是由于模拟器中使用的Halo Occupation Distribution模型的故障。最后，我们进行了一个强大的分析可能来源的系统，包括红移的不确定性和不完整性的影响，由于目标的选择，不包括在以前的分析拟合聚类测量小尺度。
We measure the small-scale clustering of the Data Release 16 extended Baryon Oscillation Spectroscopic Survey Luminous Red Galaxy sample, corrected for fibre-collisions using Pairwise Inverse Probability weights, which give unbiased clustering measurements on all scales. We fit to the monopole and quadrupole moments and to the projected correlation function over the separation rangewith a model based on theaemuluscosmological emulator to measure the growth rate of cosmic structure, parametrized byfσ8. We obtain a measurement offσ8(z= 0.737) = 0.408 ± 0.038, which is 1.4σlower than the value expected from 2018 Planck data for a flat ΛCDM model, and is more consistent with recent weak-lensing measurements. The level of precision achieved is 1.7 times better than more standard measurements made using only the large-scale modes of the same sample. We also fit to the data using the full range of scalesmodelled by theaemuluscosmological emulator and find a 4.5σtension in the amplitude of the halo velocity field with the Planck + ΛCDM model, driven by a mismatch on the non-linear scales. This may not be cosmological in origin, and could be due to a breakdown in the Halo Occupation Distribution model used in the emulator. Finally, we perform a robust analysis of possible sources of systematics, including the effects of redshift uncertainty and incompleteness due to target selection that were not included in previous analyses fitting to clustering measurements on small scales.