Abstract

Contributed Talk - Splinter LIM

Friday, 11 September 2026, 14:20   (MW-2050)

An invertible simulator for efficient reconstruction of dark matter density from line intensity maps

Thomas Blankenburg, Caroline Heneka
Institut für Theoretische Physik, Heidelberg

Observations of the large-scale structure, such as intensity maps of the 21cm line of neutral hydrogen, raise the question whether a precise, robust, and efficient mapping can be established from these observables to the underlying dark matter density field. We present a direct diffusion framework based on Conditional Flow Matching that enables accurate reconstruction of dark matter density from both simulated 21cm brightness temperature maps and realistic mock observations for the Square Kilometre Array, across a broad range of ionization fractions and astrophysical parameters. Furthermore, we demonstrate that our invertible method can also function as a simulator, generating both simulated and mock 21cm observations from dark matter density fields along with the corresponding ionization masks. Our approach provides a robust and efficient bridge between large-scale structure observations and the underlying dark matter distribution.