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arXiv · 2512.12376

The Universal Bayesian Imaging Kit

Torsten Enßlin·Vincent Eberle·Matteo Guardiani·Margret Westerkamp
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Abstract

Bayesian imaging of astrophysical measurement data shares universal properties across the electromagnetic spectrum: it requires probabilistic descriptions of possible images and spectra, and instrument responses. To unify Bayesian imaging, we present the Universal Bayesian Imaging Kit (UBIK). Currently, UBIK images data from Chandra, eROSITA, JWST, and ALMA. UBIK is based on information field theory (IFT), the mathematical theory of field inference, and on NIFTy, a package for numerical IFT. UBIK provides sky models that are instrument independent and instrument interfaces that share common parts of their response representations. It is open source, can provide spatio-spectral image cubes, jointly analyses data from several instruments, and separates diffuse emission, point sources, and extended emission regions.

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Torsten Enßlin, Vincent Eberle, Matteo Guardiani, Margret Westerkamp. 2025-12-13. The Universal Bayesian Imaging Kit. https://arxiv.org/abs/2512.12376

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