Conveners
Galactic Center
- Luciano Rezzolla (Goethe University of Frankfurt)
For the past two decades, flares (i.e. outbursts of radiation) have been observed from the centre of the Milky Way where a massive compact object of 4.3 millions solar masses resides at only 8.3 kpc. This makes this object called Sgr A* the closest supermassive black hole candidate to Earth and an unique laboratory for relativistic astrophysics. Recent observations have shown that the source...
We report on a first detection of an orbiting hot spot in ALMA polarimetric light curves of Sagittarius A*, manifesting in the loop-like patterns on the linear polarization Q-U plane following the X-ray flare detected by Chandra. The observed hot spot period corresponds to about 70 minutes, and the implied orbital radius corresponds to about 5 Schwarzschild radii. These new observations...
I will summarize our current understanding of dust-enshrouded sources that are observed in the S cluster around the supermassive black hole (SMBH). Currently, we observe a population of about 10 sources that share common characteristics: a prominent near-infrared excess and rather broad emission lines (Br-gamma, HeI). These sources are quite distinct from the majority of the surrounding B-type...
We are fitting dynamics of electrically neutral hot-spot orbiting around Sagittarius A* source in Galactic centre, represented by various modifications of the standard Kerr black hole, to the three flares observed by the GRAVITY instrument. We consider stationary, axisymmetric, and asymptotically flat spacetimes describing charged black holes in general relativity combined with nonlinear...