NeuralPDR: neural differential equations as surrogate models for photodissociation regions

Machine Learning Science and Technology, vol. 6, pp. 025069

Abstract

Abstract Computational astrochemical models are essential for helping us interpret and understand the observations of different astrophysical environments. In the age of high-resolution telescopes such as JWST and ALMA, the substructure of many objects can be resolved, raising the need for astrochemical modeling at these smaller scales, meaning that the simulations of these objects need to include both the physics and chemistry to accurately model the observations. The computational cost of the simulations coupling both the three-dimensional hydrodynamics and chemistry is enormous, creating an opportunity for surrogate models that can effectively substitute the chemical solver. In this work we present surrogate models that can replace the original chemical code, namely Latent Augmented Neural Ordinary Differential Equations. We train these surrogate architectures on three datasets of increasing physical complexity, with the last dataset derived directly from a three-dimensional simulation of a molecular cloud using a photodissociation region (PDR) code, 3D-PDR . We show that these surrogate models can provide speedup and reproduce the original observable column density maps of the dataset. This enables the rapid inference of the chemistry (on the GPU), allowing for the faster statistical inference of observations or increasing the resolution in hydrodynamical simulations of astrophysical environments.

Authors 4

1. Gijs Vermariën corresponding Aachen Leiden Observatory

   Leiden University · SURF · Leiden Observatory

   Affiliation as printed

   Leiden Observatory, Leiden University, PO Box 9513, 2300 RA Leiden, The Netherlands

   SURF, Amsterdam, The Netherlands

2. Thomas G. Bisbas corresponding

   Zhejiang Lab

   Affiliation as printed

   Research Center for Astronomical Computing, Zhejiang Lab, Hangzhou 311100, People's Republic of China

3. S. Viti corresponding Aachen Leiden Observatory

   Leiden University · University of Bonn · Leiden Observatory · University College London

   Affiliation as printed

   Department of Physics and Astronomy, University College London, Gower Street, London, United Kingdom

   Leiden Observatory, Leiden University, PO Box 9513, 2300 RA Leiden, The Netherlands

   Transdisciplinary Research Area (TRA)'Matter'/Argelander-Institut für Astronomie, University of Bonn, Bonn, Germany

4. Yue Zhao corresponding

   SURF

   Affiliation as printed

   SURF, Amsterdam, The Netherlands