发表机构
University of Edinburgh; University of Michigan; University of Hertfordshire; Universidad Nacional Autónoma de México; University of Sussex; Ohio University; University of Waterloo; CEA, Université Paris-Saclay（爱丁堡大学; 密歇根大学; 赫特福德大学; 墨西哥国立自治大学; 萨塞克斯大学; 俄亥俄大学; 滑铁卢大学; 法国原子能和替代能源委员会，巴黎萨克雷大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究联合DESI DR1的功率谱与双谱进行全形状宇宙学推断，在有效场论框架下建模，发现双谱单极矩显著改善冷暗物质密度和涨落振幅约束，展示了高阶统计量提升宇宙学参数精度的潜力。
AI 中文摘要
星系双谱直接探测大尺度结构（LSS）的非线性引力演化，并能打破功率谱分析中残留的参数简并。我们提出了对暗能量光谱仪（DESI）首次数据发布（DR1）中三个发光红星系（LRG）红移区间和类星体（QSO）样本的联合全形状宇宙学分析。我们在有效场论框架下对红移空间功率谱进行单圈级建模，并对双谱进行树级建模。双谱在三角极球谐函数基下分解，其与巡天窗口函数的卷积可表述为理论多极矩的直接线性变换。我们的功率谱约束与官方DESI DR1全建模结果高度一致。我们研究了在推断中加入双谱的影响，发现在单个示踪物分析中，单极矩使冷暗物质密度和物质涨落振幅的约束分别显著改善9-18%和8-20%。对于组合LRG样本，相应改善为15%和10%；当所有示踪物组合时，改善为6%和4%。在使用第一个LRG区间的受限测试中，双谱四极矩仅使边缘化不确定度改变几个百分点。将分析扩展到$w_0w_a$CDM模型会显著拓宽宇宙学后验分布，而双谱对允许的暗能量参数区域仅产生轻微改变，该区域仍对采用的先验范围敏感。我们的结果证明了高阶聚类统计量在改善宇宙学约束方面的潜力，同时为将双谱纳入当前和未来光谱星系巡天的全形状分析提供了框架。
英文摘要
The galaxy bispectrum directly probes the non-linear gravitational evolution of large-scale structure (LSS) and can break parameter degeneracies that remain in power-spectrum analyses. We present a joint full-shape cosmological analysis of three luminous red galaxy (LRG) redshift bins and the quasar (QSO) sample from the first Data Release (DR1) of the Dark Energy Spectroscopic Instrument (DESI). We model the redshift-space power spectrum at one loop and the tree-level bispectrum within the Effective Field Theory of LSS. The bispectrum is decomposed in the Tripolar Spherical Harmonics basis, for which the convolution with the survey window function can be formulated as a direct linear transformation of the theoretical multipoles. Our power-spectrum constraints are in good agreement with the official DESI DR1 full-modelling results. We investigate the impact of including the bispectrum in the inference, finding that the monopole substantially improves the constraints on the cold dark matter density and amplitude of matter fluctuations by 9-18% and 8-20%, respectively, in the individual-tracer analyses. The corresponding reductions are 15% and 10% for the combined LRG sample, and 6% and 4% when all tracers are combined. In a restricted test using the first LRG bin, the bispectrum quadrupole changes the marginalised uncertainties by only a few percent. Extending the analysis to $w_0w_a$CDM substantially broadens the cosmological posteriors, while the bispectrum produces only a mild change in the allowed dark-energy parameter region, which remains sensitive to the adopted prior ranges. Our results demonstrate the potential of higher-order clustering statistics to improve cosmological constraints, while providing a framework for incorporating the bispectrum into full-shape analyses of current and future spectroscopic galaxy surveys.
Comments53 pages, 16 figures
