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arXiv · 2512.12728

DAO: A New and Public Non-Relativistic Reflection Model

Yimin Huang·Honghui Liu·Cosimo Bambi·Adam Ingram·Jiachen Jiang·Andrew Young·Zuobin Zhang
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Abstract

We present a new non-relativistic reflection model, DAO, designed to calculate reflection spectra in the rest frame of accretion disks in X-ray binaries and active galactic nuclei. The model couples the XSTAR code, which treats atomic processes, with the Feautrier method for solving the radiative transfer equation. A key feature of DAO is the incorporation of a high-temperature corrected cross section and an exact redistribution function to accurately treat Compton scattering. Furthermore, the model accommodates arbitrary illuminating spectra, enabling applications across diverse physical conditions. We investigate the spectral dependence on key physical parameters and benchmark the results against the widely used reflionx and xillver codes.

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Yimin Huang, Honghui Liu, Cosimo Bambi, Adam Ingram, Jiachen Jiang, Andrew Young, Zuobin Zhang. 2025-12-14. DAO: A New and Public Non-Relativistic Reflection Model. https://arxiv.org/abs/2512.12728

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