SPECULATOR: Emulating stellar population synthesis for fast and accurate galaxy spectra and photometry

Abstract

We present SPECULATOR - a fast, accurate, and flexible framework for emulating stellar population synthesis (SPS) models for predicting galaxy spectra and photometry. For emulating spectra, we use principal component analysis to construct a set of basis functions, and neural networks to learn the basis coefficients as a function of the SPS model parameters. For photometry, we parameterize the magnitudes (for the filters of interest) as a function of SPS parameters by a neural network. The resulting emulators are able to predict spectra and photometry under both simple and complicated SPS model parameterizations to percent-level accuracy, giving a factor of $10^3$-$10^4$ speed up over direct SPS computation. They have readily-computable derivatives, making them amenable to gradient-based inference and optimization methods. The emulators are also straightforward to call from a GPU, giving an additional order-of-magnitude speed-up. Rapid SPS computations delivered by emulation offers a massive reduction in the computational resources required to infer the physical properties of galaxies from observed spectra or photometry and simulate galaxy populations under SPS models, whilst maintaining the accuracy required for a range of applications.

15 pages, 9 figures, accepted by ApJS April 2020

References in corpus (46)

• TensorFlow: Large-Scale Machine Learning on Heterogeneous Distributed Systems
• The Dust Content and Opacity of Actively Star-Forming Galaxies
• Modules for Experiments in Stellar Astrophysics (MESA)
• Modules for Experiments in Stellar Astrophysics (MESA): Giant Planets, Oscillations, Rotation, and Massive Stars
• Modules for Experiments in Stellar Astrophysics (MESA): Binaries, Pulsations, and Explosions
• MESA Isochrones and Stellar Tracks (MIST). I: Solar-Scaled Models
• Introducing the Illustris Project: Simulating the coevolution of dark and visible matter in the Universe
• CANDELS: The Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey
• CANDELS: The Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey - The Hubble Space Telescope Observations, Imaging Data Products and Mosaics
• MESA Isochrones and Stellar Tracks (MIST) 0: Methods for the construction of stellar isochrones
• The propagation of uncertainties in stellar population synthesis modeling I: The relevance of uncertain aspects of stellar evolution and the IMF to the derived physical properties of galaxies
• A Simple Model for the Absorption of Starlight by Dust in Galaxies
• Properties of galaxies reproduced by a hydrodynamic simulation
• Activation Functions: Comparison of trends in Practice and Research for Deep Learning
• The DESI Experiment Part I: Science,Targeting, and Survey Design
• The ages and metallicities of galaxies in the local universe
• The propagation of uncertainties in stellar population synthesis modeling III: model calibration, comparison, and evaluation
• 3D-HST WFC3-selected Photometric Catalogs in the Five CANDELS/3D-HST Fields: Photometry, Photometric Redshifts and Stellar Masses
• Modeling the Panchromatic Spectral Energy Distributions of Galaxies
• Constraining the Low-Mass Slope of the Star Formation Sequence at 0.5<z<2.5
• 3D-HST: A wide-field grism spectroscopic survey with the Hubble Space Telescope
• Deriving Physical Properties from Broadband Photometry with Prospector: Description of the Model and a Demonstration of its Accuracy Using 129 Galaxies in the Local Universe
• The NEWFIRM Medium-band Survey: Photometric Catalogs, Redshifts and the Bimodal Color Distribution of Galaxies out to z~3
• The Stellar Initial Mass Function in Early-Type Galaxies From Absorption Line Spectroscopy. II. Results
• Modelling and interpreting spectral energy distributions of galaxies with BEAGLE
• Nebular Continuum and Line Emission in Stellar Population Synthesis Models
• A Public Ks-selected Catalog in the COSMOS/UltraVISTA Field: Photometry, Photometric Redshifts and Stellar Population Parameters
• A physical model for cosmological simulations of galaxy formation: multi-epoch validation
• An Older, More Quiescent Universe from Panchromatic SED Fitting of the 3D-HST Survey
• MOSFIRE Spectroscopy of Quiescent Galaxies at 1.5 < z < 2.5. II - Star Formation Histories and Galaxy Quenching
• The VANDELS survey: the star-formation histories of massive quiescent galaxies at 1.0 < z < 1.3
• The WIRCam Deep Survey I: Counts, colours and mass-functions derived from near-infrared imaging in the CFHTLS deep fields
• CARS: the CFHTLS-Archive-Research Survey; I. Five-band multi-colour data from 37 sq. deg. CFHTLS-Wide observations
• The evolution of star formation histories of quiescent galaxies
• Metal-rich, Metal-poor: Updated Stellar Population Models for Old Stellar Systems
• Constructing A Flexible Likelihood Function For Spectroscopic Inference
• Nuisance hardened data compression for fast likelihood-free inference
• A catalog of mid-infrared sources in the Extended Groth Strip
• Hot dust in Panchromatic SED Fitting: Identification of AGN and improved galaxy properties
• Log-normal star formation histories in simulated and observed galaxies
• The Evolution and Properties of Rotating Massive Star Populations
• Bayesian emulator optimisation for cosmology: application to the Lyman-alpha forest
• BayeSED: A General Approach to Fitting the Spectral Energy Distribution of Galaxies
• Learning the Fundamental MIR Spectral Components of Galaxies with Non-Negative Matrix Factorisation
• Posterior inference unchained with EL_2O
• Estimating Spectra from Photometry

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• Stellar Population Inference with Prospector
• COSMOPOWER: emulating cosmological power spectra for accelerated Bayesian inference from next-generation surveys
• Cosmological constraints from the tomographic cross-correlation of DESI Luminous Red Galaxies and Planck CMB lensing
• JWST reveals a population of ultra-red, flattened disk galaxies at 2<z<6 previously missed by HST
• Inferring More from Less: Prospector as a Photometric Redshift Engine in the Era of JWST
• The UNCOVER Survey: A First-look HST+JWST Catalog of Galaxy Redshifts and Stellar Population Properties Spanning $0.2\lesssim z\lesssim 15$
• CONNECT: A neural network based framework for emulating cosmological observables and cosmological parameter inference
• Accelerated Bayesian SED Modeling using Amortized Neural Posterior Estimation
• SBI++: Flexible, Ultra-fast Likelihood-free Inference Customized for Astronomical Applications
• Forward modeling of galaxy populations for cosmological redshift distribution inference
• $\text{matryoshka}$: Halo Model Emulator for the Galaxy Power Spectrum
• Autoencoding Galaxy Spectra I: Architecture
• Hierarchical Bayesian inference of photometric redshifts with stellar population synthesis models
• The DESI PRObabilistic Value-Added Bright Galaxy Survey (PROVABGS) Mock Challenge
• pop-cosmos: A comprehensive picture of the galaxy population from COSMOS data
• Surrogate modelling the Baryonic Universe II: on forward modelling the colours of individual and populations of galaxies
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• On The Impact Of 22Ne On The Pulsation Periods Of Carbon-Oxygen White Dwarfs With Helium Dominated Atmospheres
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• PopSED: Population-Level Inference for Galaxy Properties from Broadband Photometry with Neural Density Estimation
• Accelerating cosmological inference with Gaussian processes and neural networks -- an application to LSST Y1 weak lensing and galaxy clustering
• Simulation-based inference of deep fields: galaxy population model and redshift distributions
• Impact of stellar population synthesis choices on forward modelling-based redshift distribution estimates
• Self-consistent population spectral synthesis with FADO: II. Star formation history of galaxies in spectral synthesis methods
• Bayesian Control Variates for optimal covariance estimation with pairs of simulations and surrogates
• pop-cosmos: Scaleable inference of galaxy properties and redshifts with a data-driven population model
• Neural Stellar Population Synthesis Emulator for the DESI PROVABGS
• Machine learning synthetic spectra for probabilistic redshift estimation: SYTH-Z
• A representation learning approach to probe for dynamical dark energy in matter power spectra
• Physical Properties of the Host Galaxies of Ca-rich Transients
• AGN X-ray Spectroscopy with Neural Networks
• Emission Line Predictions for Mock Galaxy Catalogues: a New Differentiable and Empirical Mapping from DESI
• MF-Box: Multi-fidelity and multi-scale emulation for the matter power spectrum
• Deep learning insights into non-universality in the halo mass function
• Leveraging Machine Learning for Accurate and Fast Stellar Mass Estimation of Galaxies
• Relativistic Reflection Modeling in AGN and Related Variability from PCA: A Brief Review
• pop-cosmos: Insights from generative modeling of a deep, infrared-selected galaxy population
• Data-Space Validation of High-Dimensional Models by Comparing Sample Quantiles
• $\Lambda$CDM and early dark energy in latent space: a data-driven parametrization of the CMB temperature power spectrum
• Impact of redshift distribution uncertainties on Lyman-break galaxy cosmological parameter inference
• Sengi: a small, fast, interactive viewer for spectral outputs from stellar population synthesis models
• Flexible Simulation Based Inference for Galaxy Photometric Fitting with Synthesizer
• QUEST (Quasar Unsupervised Encoder and Synthesis Tool): A machine learning framework to generate quasar spectra
• CIGaRS I: Combined simulation-based inference from type Ia supernovae and host photometry
• On the accuracy of posterior recovery with neural network emulators
• GalSBI: Phenomenological galaxy population model for cosmology using simulation-based inference
• pop-cosmos: Star formation over 12 Gyr from generative modelling of a deep infrared-selected galaxy catalogue
• SE3D: Building a radiative transfer emulator to fit panchromatic resolved galaxy observations with 3D models of dust and stars
• Towards model-free stellar chemical abundances. Potential applications in the search for chemically peculiar stars in large spectroscopic surveys
• Neural Network Acceleration of Large-scale Structure Theory Calculations
• GalSBI-SPS: a stellar population synthesis-based galaxy population model for cosmology and galaxy evolution applications