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arXiv · 2412.08722

galsbi: A Python package for the GalSBI galaxy population model

Silvan Fischbacher·Beatrice Moser·Tomasz Kacprzak·Joerg Herbel·Luca Tortorelli·Uwe Schmitt·Alexandre Refregier·Adam Amara
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Abstract

Large-scale structure surveys measure the shapes and positions of millions of galaxies in order to constrain the cosmological model with high precision. The resulting large data volume poses a challenge for the analysis of the data, from the estimation of photometric redshifts to the calibration of shape measurements. We present GalSBI, a model for the galaxy population, to address these challenges. This phenomenological model is constrained by observational data using simulation-based inference (SBI). The $\texttt{galsbi}$ Python package provides an easy interface to generate catalogs of galaxies based on the GalSBI model, including their photometric properties, and to simulate realistic images of these galaxies using the $\texttt{UFig}$ package.

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Silvan Fischbacher, Beatrice Moser, Tomasz Kacprzak, Joerg Herbel, Luca Tortorelli, Uwe Schmitt, Alexandre Refregier, Adam Amara. 2024-12-11. galsbi: A Python package for the GalSBI galaxy population model. https://doi.org/10.21105/joss.08766

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