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arXiv · 2603.00833

Accretion Geometry of Black Hole X-ray Binaries: Insights from X-ray Observations

Honghui Liu
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Abstract

The accretion-ejection activities of black holes play a vital role in shaping the Universe. Bright and recurrent black hole X-ray binaries are ideal objects for studying accretion physics across a wide range of accretion rates, providing insights into the understanding of their supermassive counterparts. This short review summarizes X-ray techniques capable of measuring accretion geometry, our current understanding, and open questions. In particular, X-ray spectroscopic studies indicate that the accretion disk can extend close to the innermost stable circular orbit in the bright hard state. Some hints of disk-corona-jet connections are also discussed.

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Honghui Liu. 2026-02-28. Accretion Geometry of Black Hole X-ray Binaries: Insights from X-ray Observations. https://doi.org/10.1007/s10509-026-04562-8

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