AI 中文总结
研究宇宙微波背景非原初贡献，引入参数\(\varepsilon_{\rm CMB}\)，通过普朗克2018等数据约束模型，发现百分之几的尘埃贡献与数据相符，给出参数范围及后验，表明当前宇宙学可容该贡献且不影响参数推断。
AI 中文摘要
宇宙微波背景被解释为红移\(z\sim1090\)复合时期的遗迹热辐射。Gjergo和Kroupa（GK25）最近的工作对此假设提出挑战，认为红移\(z\sim15 - 20\)的大质量早期星系前身中被尘埃笼罩的星暴对宇宙微波背景的贡献为当前宇宙微波背景能量密度的百分之几。现有对此情景的测试依赖于宇宙微波背景单极；本文首次针对宇宙微波背景各向异性功率谱进行测试，该谱探测辐射内容在声视界和声学峰上的动力学印记。我们引入一个单参数\(\varepsilon_{\rm CMB}\)，它能重新调整红移（\(z = 17\)）以上的原初光子能量密度。用普朗克2018、透镜似然性和重子声学振荡测量来约束模型，我们发现百分之几的尘埃贡献与数据完全一致。当限制\(\varepsilon_{\rm CMB}\leq1\)时，数据给出68（95）%的下限\(\varepsilon_{\rm CMB}\gtrsim 0.971\)（\(0.953\)），允许非原初贡献高达宇宙微波背景能量密度的约3（5）%。以\(\varepsilon_{\rm CMB}\)为自由参数采样时，数据给出分辨率良好的后验，\(\varepsilon_{\rm CMB} = 1.0104^{+0.025}_{-0.024}\)。GK25保守估计的1.4%贡献在两种情况的1\(\sigma\)区域内，而接近全宇宙微波背景能量密度的贡献在42\(\sigma\)水平被排除。将\(z\)视为自由参数时，在\(5 < z < 50\)范围内得到平坦后验，表明各向异性限制了尘埃贡献，但不限制其发生时间。标准ΛCDM参数恢复时无显著偏移，表明当前宇宙微波背景精确宇宙学有足够空间容纳GK25预测水平的尘埃贡献，且对参数推断无可检测影响。
英文摘要
The cosmic microwave background is interpreted as relic thermal radiation from the epoch of recombination at z~1090. Recent work by Gjergo & Kroupa (GK25) have challenged this assumption proposing that dust-enshrouded starbursts in the progenitors of massive early-type galaxies at z~15-20 contribute to the CMB at the percent level of the present-day CMB energy density. Existing test of this scenario rely on CMB monopole; here we present the first test against the CMB anisotropy power spectrum, which probes the dynamical imprint of the radiation content on the sound horizon and acoustic peaks. We introduce a single parameter $\varepsilon_{\rm CMB}$ that rescales the primordial photon energy density above a redshift (z=17). Constraining the model with the Planck 2018, lensing likelihoods and BAO measurements, we find a percent-level dust contribution to be fully consistent with the data. When we restrict $\varepsilon_{\rm CMB}\leq1$, the data place a 68 (95) per cent lower bound $\varepsilon_{\rm CMB}\gtrsim 0.971$(0.953), permitting a non-primordial contribution of up to ~3 (~5) per cent of the CMB energy density. When sampled with $\varepsilon_{\rm CMB}$ as a free parameter, the data yield a well-resolved posterior with $\varepsilon_{\rm CMB} = 1.0104^{+0.025}_{-0.024}$. The 1.4 per cent contribution conservatively estimated by GK25 lies within the 1$σ$ region of both cases, whereas a contribution approaching the full CMB energy density is excluded at 42$σ$. Treating z as a free parameter returns a flat posterior across 5<z<50 indicating the anisotropy constrains the dust contribution, but not when it occurs. The standard LCDM parameters are recovered without significant shifts, showing that current CMB precision cosmology has sufficient room to accommodate a dust contribution at the level predicted by GK25 without detectable consequence for parameter inference.
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