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arXiv · 2407.16009

TensorFlow Hydrodynamics Analysis for Ly-$\alpha$ Simulations

Jupiter Ding·Benjamin Horowitz·Zarija Lukić
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Abstract

We introduce the Python program THALAS (TensorFlow Hydrodynamics Analysis for Lyman-Alpha Simulations), which maps baryon fields (baryon density, temperature, and velocity) to Ly$\alpha$ optical depth fields in both real space and redshift space. Unlike previous Ly$\alpha$ codes, THALAS is fully differentiable, enabling a wide variety of potential applications for general analysis of hydrodynamical simulations and cosmological inference. To demonstrate THALAS's capabilities, we apply it to the Ly$\alpha$ forest inversion problem: given a Ly$\alpha$ optical depth field, we reconstruct the corresponding real-space dark matter density field. Such applications are relevant to both cosmological and three-dimensional tomographic analyses of Lyman Alpha forest data.

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Jupiter Ding, Benjamin Horowitz, Zarija Lukić. 2024-07-22. TensorFlow Hydrodynamics Analysis for Ly-$\alpha$ Simulations. https://doi.org/10.1016/j.ascom.2024.100858

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