English

Resolving Horizon-Scale Dynamics of Sagittarius A*

High Energy Astrophysical Phenomena 2023-10-27 v1 Astrophysics of Galaxies Instrumentation and Methods for Astrophysics

Abstract

Sagittarius A* (Sgr A*), the supermassive black hole at the heart of our galaxy, provides unique opportunities to study black hole accretion, jet formation, and gravitational physics. The rapid structural changes in Sgr A*'s emission pose a significant challenge for traditional imaging techniques. We present dynamic reconstructions of Sgr A* using Event Horizon Telescope (EHT) data from April 6th and 7th, 2017, analyzed with a one-minute temporal resolution with the Resolve framework. This Bayesian approach employs adaptive Gaussian Processes and Variational Inference for data-driven self-regularization. Our results not only fully confirm the initial findings by the EHT Collaboration for a time-averaged source but also reveal intricate details about the temporal dynamics within the black hole environment. We find an intriguing dynamic feature on April 6th that propagates in a clock-wise direction. Geometric modelling with ray-tracing, although not fully conclusive, indicates compatibility with high-inclination configurations of about θo=160\theta_o = 160^\circ, as seen in other studies.

Keywords

Cite

@article{arxiv.2310.16889,
  title  = {Resolving Horizon-Scale Dynamics of Sagittarius A*},
  author = {Jakob Knollmüller and Philipp Arras and Torsten Enßlin},
  journal= {arXiv preprint arXiv:2310.16889},
  year   = {2023}
}
R2 v1 2026-06-28T13:01:58.759Z