activity
20232026
most citedNear-Horizon Polarization as a Diagnostic of Black Hole Spacetime

19 citations · 37 across the 25 of their papers we have counts for

collaborators

25 papers

astro-ph.HE2026

Dense Dump Codec: Error-Controlled, Random-Access Compression of GRMHD Time Series for Slow-Light Radiative Transfer

Zelin Zhang, Zhenyu Zhang, Bin Chen

Black-hole movies provide a unique venue to study the time evolution of accreting plasma. Modeling this evolution with slow-light radiative transfer requires closely spaced simulat…

astro-ph.HE2026

KPolaris: GPU-accelerated Polarized Radiative Transfer in General Relativity

Zelin Zhang, Bin Chen

Polarized black-hole images carry information about both the magnetized plasma and the curved spacetime through which the radiation propagates. We present KPolaris, an open-source…

gr-qc2026

Thermodynamics of Kerr-Newman-Bertotti-Robinson black holes

Zelin Zhang, Zhenyu Zhang, Bin Chen

In this work, we extend the thermodynamic analyses of the neutral and specially charged Kerr-Bertotti-Robinson black holes to the general Kerr-Newman-Bertotti-Robinson family, in w…

gr-qc2026

Shadows and Thin-Disk Images of Kerr-Newman Black Holes in a Bertotti-Robinson Magnetic Field

Xi Wan, Haiyu Wang, Zhenyu Zhang +2

In this paper, we investigate the optical properties of Kerr-Newman-Bertotti-Robinson (KN-BR) black holes. We use the separability of null geodesics to analyze unstable spherical p…

astro-ph.HE2026

CoportSL: A Contribution-constrained Hybrid Slow-light Framework for Time-dependent Polarized GRMHD Imaging

Fan Zhou, Jiewei Huang, Yuehang Li +2

Fast-light approximations neglect fluid evolution along rays, whereas slow-light modeling is indispensable for recovering the true magnetohydrodynamic state. However, full slow-lig…

gr-qc2026

Completing the Penrose Process without a Horizon

Yang Huang, Shiyang Hu, Bin Chen +1

In its standard black-hole realization, the Penrose process uses an event horizon to remove a negative-energy fragment. We show that, at the kinematic level, horizon absorption can…

astro-ph.HE2026

Polarization Architecture of Steady GRMHD Jets from the Horizon to Infinity

Zhenyu Zhang, Yehui Hou, Yu Song +2

We develop a semi-analytic framework for stationary, axisymmetric GRMHD jets that efficiently generates resolved polarized images from the near-horizon region out to $\sim 10^5\,r_…

gr-qc2026

Distinct Near-Horizon Trend of Synchrotron Polarization in Kerr Spacetime

Yehui Hou, Jiewei Huang, Bin Chen

We show that the near-horizon expansion of the linear polarization vector for synchrotron emission in a Kerr background admits a distinct analytic form. For emission from a station…

gr-qc2026

Distorting Kerr Images with Parity-Odd Scalar Hair

Qian Wan, Yehui Hou, Yang Huang +3

We investigate thin-disk imaging of Kerr black holes with synchronized scalar hair, focusing on backreacted parity-odd excited states of a complex scalar field minimally coupled to…

astro-ph.HE2026

Black Hole Ringdown Seen in Photon Polarization Swings

Jiewei Huang, Yehui Hou, Zhen Zhong +2

Light propagating through a perturbed spacetime could imprint the underlying gravitational waveform directly onto electromagnetic observables. In this Letter, we develop a covarian…

astro-ph.HE2026

Testing solitonic boson star interpretations of Sagittarius A* with near-infrared flare astrometry

Xiangyu Wang, Zhenyu Zhang, Hai-Qing Zhang +2

We use GRAVITY near-infrared (NIR) flare astrometry to test whether Sagittarius A* could be a solitonic boson star. We consider five spherically symmetric solitonic boson-star mode…

gr-qc2026

Critical Behavior of Photon Rings in Kerr-Bertotti-Robinson Spacetime

Xi Wan, Zhenyu Zhang, Fang-Stars Wei +2

In this work, we investigate the critical behavior of photon rings in the Kerr-Bertotti-Robinson spacetime, describing a rotating black hole immersed in a background magnetic field…

astro-ph.HE2025★ 3 cited

Non-thermal Synchrotron Emission and Polarization Signatures during Black Hole Flux Eruptions

Fan Zhou, Jiewei Huang, Yuehang Li +4

In this work, we investigate synchrotron emission and the observational signatures of anisotropic non-thermal electrons during magnetic-flux eruptions in a magnetically arrested di…

astro-ph.HE2025

Probing the Penrose Process: Images of Split Hotspots and Their Observational Signatures

Zhixing Zhao, Zhong-Ying Fan, Xiaobao Wang +2

While theoretically established for decades, the Penrose process - energy extraction from rotating black holes - still lacks clear observational evidence. A promising theoretical f…

gr-qc2025

Semi-analytical Study on the Polarized Images of Black Hole due to Frame Dragging

Xinyu Wang, Songbai Chen, Minyong Guo +1

An initially retrograde accretion flow is transformed into a prograde configuration before plunging into the black hole, as a result of the frame-dragging effect induced by the bla…

astro-ph.HE2025

Hybrid Black Hole and Disk-Driven Jets: Steady Axisymmetric Ideal MHD Modeling

Yu Song, Yehui Hou, Lei Huang +1

Improved observational precision in relativistic jets has underscored the need for tractable theoretical models. In this study, we construct a semi-analytical hybrid jet model that…

gr-qc2025

Geodesics and Shadows in the Kerr-Bertotti-Robinson Black Hole Spacetime

Xinyu Wang, Yehui Hou, Xi Wan +2

In this work, we investigate geodesics and black hole shadows in the Kerr-Bertotti-Robinson spacetime. We show that the equations of motion for null geodesics are separable and adm…

astro-ph.HE2025

Autocorrelation signatures in time-resolved black hole flare images: secondary peaks and convergence structure

Zhenyu Zhang, Yehui Hou, Minyong Guo +2

The strong gravitational field of a black hole bends light, forming multi-level images, yet extracting precise spacetime information from them remains challenging. In this study, w…

astro-ph.HE2024★ 11 cited

Magnetic reconnection under centrifugal and gravitational electromotive forces

Zhong-Ying Fan, Fan Zhou, Yuehang Li +2

We examine the physical implications of the centrifugal and gravitational electromotive forces on magnetic reconnection in a Kerr black hole background. We find that both forces in…

gr-qc2024★ 19 cited

Near-Horizon Polarization as a Diagnostic of Black Hole Spacetime

Yehui Hou, Jiewei Huang, Minyong Guo +2

A key challenge in imaging supermassive black holes is disentangling gravitational effects from plasma physics in order to accurately determine spacetime properties, particularly b…

astro-ph.HE2024

Polarization Patterns of the Hotspots Plunging into a Kerr Black Hole

Bin Chen, Yehui Hou, Yu Song +1

The multi-wavelength polarized light signals from supermassive black holes have sparked many studies on polarized images of accretion disks and hotspots. However, the polarization…

astro-ph.HE2024

Coport: A New Public Code for Polarized Radiative Transfer in a Covariant Framework

Jiewei Huang, Liheng Zheng, Minyong Guo +1

General relativistic radiative transfer calculations are essential for comparing theoretical models of black hole accretion flows and jets with observational data. In this work, we…

gr-qc2024

Images and flares of geodesic hotspots around a Kerr black hole

Jiewei Huang, Zhenyu Zhang, Minyong Guo +1

In this study, we develop a numerical method to generate images on an observer's screen, formed by radiation from hotspots on any timelike orbits outside a black hole. This method…

astro-ph.HE2024★ 2 cited

Imaging thick accretion disks and jets surrounding black holes

Zhenyu Zhang, Yehui Hou, Minyong Guo +1

Based on the horizon-scale magnetofluid model developed in [arXiv:2309.13304], we investigate the millimeter-wave images of a geometrically thick accretion disk or a funnel wall, i…