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arXiv 2305.09720astro-ph.COgr-qc
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HI强度映射功率谱:来自近期测量的洞见

The HI intensity mapping power spectrum: insights from recent measurements

Hamsa Padmanabhan, Roy Maartens, Obinna Umeh, Stefano Camera

AI总结:

本研究基于MeerKAT望远镜首次测得的红移0.32、0.44处HI强度映射功率谱,构建含1晕项等效应的红移空间小尺度功率模型,验证其在0.32红移处拟合良好,0.44处需调整HI丰度或晕偏置。

摘要:

近期,科研人员利用MeerKAT望远镜首次直接测量了HI(中性氢)强度映射功率谱。这些测量针对红移0.32和0.44处的非线性尺度展开。我们在质量加权HI晕模型框架下,建立了一套用于模拟红移空间中小尺度功率的形式体系,该模型与最新巡天得到的HI-晕质量关系研究结果一致。为模拟非线性尺度,我们纳入了1晕项、散粒噪声和上帝之指效应。随后将该模型应用于MeerKAT自相关数据,发现模型在红移0.32处能很好拟合数据,但z~0.44处的数据可能显示出需要调整的迹象,这种调整可通过提升HI丰度或晕模型偏置实现。

英文摘要:

The first direct measurements of the HI intensity mapping power spectrum were recently made using the MeerKAT telescope. These measurements are on nonlinear scales, at redshifts 0.32 and 0.44. We develop a formalism for modelling small-scale power in redshift space, within the context of the mass-weighted HI halo model framework. This model is consistent with the latest findings from surveys on the HI-halo mass relation. In order to model nonlinear scales, we include the 1-halo, shot-noise and finger-of-god effects. Then we apply the model to the MeerKAT auto-correlation data, finding that the model provides a good fit to the data at redshift 0.32, but the data may indicate some evidence for an adjustment at $z \sim 0.44$. Such an adjustment can be achieved by an increase in the HI abundance or halo model bias.

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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