AI 中文总结
该研究用UMAP对JWST与HST测光流量降维构建2D嵌入，以χ²类度量比较JAGUAR等五个星系形成模型，发现JAGUAR对亮星系的再现效果远优于其他模型，且该方法速度快，可用于大型巡天的模型约束。
AI 中文摘要
星系观测与理论预测的比较通常通过物理属性进行，这些属性需通过往往缓慢且存在偏差的SED拟合过程推断。正向建模提供了一种可靠的替代方案，该方案仅使用直接观测量评估模型。然而，当整理多个望远镜的观测数据时，这些数据集会变为高维，导致采样稀疏、内存密集且可视化困难。我们展示，使用非线性降维算法UMAP构建的JWST与HST测光流量的2D嵌入保留了足够信息，可区分五种模型。使用类似χ²的简单度量，我们表明JAGUAR对GOODS-S中亮星系（m_AB<26）总体的再现效果是SC-SAM的6倍，是SAGE的12倍。通过调整超参数，我们量化了每个模型再现SED形状分布的程度。SPRITZ的模板SED方法以及SAGE缺乏光电离过程导致了显著差异，凸显了全面正向建模的重要性。每个星系的嵌入位置识别速度比通过贝叶斯SED拟合推断其属性快100倍以上，使该方法成为从LSST、Euclid等大型巡天中推导统计模型约束，以及使用CAMELS进行基于模拟的推理的理想替代方案。
英文摘要
Comparisons between observations of galaxies and theoretical predictions are regularly performed using physical properties, which are inferred by the often slow and biased process of SED fitting. Forward modelling facilitates a reliable alternative, whereby models are evaluated using direct observables alone. However, these datasets become high-dimensional when collating observations from multiple telescopes, leading to sparse sampling, memory intensity and visualisation difficulties. We show that 2D embeddings of JWST and HST photometric fluxes, constructed using the non-linear dimensionality reduction algorithm UMAP, preserve sufficient information to differentiate between five models. Using a simple $χ^{2}$-like metric, we show that JAGUAR reproduces the population of bright galaxies $(m_{\mathrm{AB}}<26)$ in GOODS-S six times as well as SC-SAM and twelve times as well as SAGE. By adjusting the hyperparameters, we quantify how well each model replicates the distribution of SED shapes. The template SED approach of SPRITZ and the lack of photoionisation in SAGE cause significant discrepancies, highlighting the importance of comprehensive forward modelling. The embedded position of each galaxy can be identified $>100$ times faster than inferring its properties with Bayesian SED fitting, making this approach an ideal alternative for deriving statistical model constraints from large surveys such as LSST and Euclid, and performing simulation-based inference with CAMELS.
Comments18 pages, 10 figures. Submitted to the Open Journal of Astrophysics
