Dissecting the variability of Sagittarius A* in the orbiting hotspot framework

arXiv:2609.28844 · astro-ph.HE, astro-ph.GA · Submitted 2026-09-23 · Read on arXiv

astro-ph.HE, astro-ph.GA

Submitted: 2026-09-23

Updated: 2026-09-23

Comments: Proceedings IAU Symposium No. 405: Traversing the Galactic Center in Space and Time

License: http://creativecommons.org/licenses/by/4.0/

The gist: Sagittarius A* (Sgr A*) exhibits intermittent flaring behavior, characterized by strong enhancements in high-energy emission (infrared and X-ray).

Terminology

Event Horizon Telescope — 8× in this paper
Consistency — 4× in this paper · explained in 3 episodes
Accretion Flows — 1× in this paper · explained in 1 episode
Accretion Physics — 1× in this paper · explained in 2 episodes
Calibration — 1× in this paper · explained in 7 episodes
Selection Bias — 1× in this paper · explained in 4 episodes

Abstract

Sagittarius A* (Sgr A*) exhibits intermittent flaring behavior, characterized by strong enhancements in high-energy emission (infrared and X-ray). These events have been interpreted as related to the coherent orbital motion of localized regions of energized plasma - hotspots. While this framework has been quite fruitful in constraining properties of Sgr A*, it is subject to important challenges and limitations. In this brief review we discuss the recent observational and theoretical developments related to this line of research, commenting on the concerns regarding the hotspot model validity and the future perspectives.

Terminology

Abstract

Related papers