SEDflow: Accelerated Bayesian SED Modeling using Amortized Neural Posterior Estimation

SEDflow is an accelerated Bayesian SED modeling method that uses the Hahn et al. (2022a) PROVABGS SED model and Amortized Neural Posterior Estimation (ANPE) to derive posterior probability distributions of galaxy properties from optical photometry. SEDflow is\(10^5\times\) faster than conventional Markov Chain Monte Carlo sampling methods and takes ~1 second per galaxy to obtain posteriors. This repository includes all of the data used to train, validate, and test SEDflow. This repository also includes a value-added catalog with detailed physical properties of 33,884 galaxies in the NASA-Sloan Atlas (http://www.nsatlas.org/). The properties are inferred from optical photometry in the <em>u, g, r, i, z</em> bands using SEDflow. For more details on this catalog and SEDflow see the documentation and Hahn &amp; Melchior (2022). For each galaxy, the catalog provides posteriors of: log_mstar: log10 of stellar mass log_sfr_1gyr: log10 of average star formation rate over 1Gyr log_z_mw: log10 of mass-weighted metallicity beta1, beta2, beta3, beta4: coefficients of the non-negative matrix factorization (NMF) star formation history basis functions fburst: fraction of stellar mass formed by a starburst event tburst: time of the starburst event log_gamma1, log_gamma2: log10 of coefficients of the NMF metallicity history basis functions tau_bc: birth cloud optical depth tau_ism: diffuse dust optical depth n_dust: Calzetti (2001) dust indexSEDflow是一种加速的贝叶斯光谱能量分布（Spectral Energy Distribution，SED）建模方法，采用Hahn等人（2022a）的PROVABGS SED模型与摊销神经后验估计（Amortized Neural Posterior Estimation，ANPE），从光学测光数据中推衍星系物理属性的后验概率分布。SEDflow的运行速度较传统马尔可夫链蒙特卡洛（Markov Chain Monte Carlo，MCMC）采样方法快10^5倍，单星系后验推导耗时仅约1秒。本仓库包含了用于训练、验证与测试SEDflow的全部数据集，同时还附带一份增值星表，收录了NASA-斯隆星图（NASA-Sloan Atlas，http://www.nsatlas.org/）中33884个星系的详细物理属性。这些属性通过SEDflow基于<em>u, g, r, i, z</em>波段的光学测光数据推导得到。有关该星表与SEDflow的更多细节，可参阅相关文档以及Hahn & Melchior（2022）的研究成果。对于每个星系，该星表提供以下参数的后验分布：log_mstar：恒星质量的log₁₀值；log_sfr_1gyr：1 Gyr内平均恒星形成率的log₁₀值；log_z_mw：质量加权金属丰度的log₁₀值；β₁、β₂、β₃、β₄：非负矩阵分解（Non-negative Matrix Factorization，NMF）恒星形成历史基函数的系数；fburst：星暴事件形成的恒星质量占比；tburst：星暴事件发生时刻；log_gamma1、log_gamma2：NMF金属丰度历史基函数系数的log₁₀值；τ_bc：诞生云光学深度；τ_ism：弥散尘埃光学深度；n_dust：Calzetti（2001）尘埃指数