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arXiv · 2609.32127

Polarization Signatures of Sgr A* with Tilted Hybrid Magnetic Fields

Yushu Feng·Hao Yin·Songbai Chen·Jiliang Jing
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Abstract

The magnetic field geometry in the near-horizon region is very important in shaping polarimetric signatures of black hole images. With a hybrid magnetic field consisting of an axisymmetric split-monopole field and a tilted uniform external field, we investigate the effects of external magnetic field inclination on the polarimetric signatures of Sgr A* by employing a stationary semi-analytical radiatively inefficient accretion flow (RIAF) model and general relativistic polarized radiative transfer simulations. Our results show that the external magnetic field tilt significantly modifies the electric vector position angle (EVPA) pattern and brightness distribution. The induced non-axisymmetry from the tilted magnetic filed component renders polarization morphology dependent on the observer's azimuthal angle, which is a novel behavior absent in purely axisymmetric magnetic field configurations. In combination with Event Horizon Telescope (EHT) data, we analyse the possibility of such hybrid magnetic fields around Sgr A*.

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Yushu Feng, Hao Yin, Songbai Chen, Jiliang Jing. 2026-09-26. Polarization Signatures of Sgr A* with Tilted Hybrid Magnetic Fields. https://arxiv.org/abs/2609.32127

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