Flares in the Galactic Centre

Several areas in modern Astrophysics involve the investigation of relativistic effects in the vicinity of a black hole or a neutron star. For example, high energy observations of the broad relativistic iron Kalpha line in the active galactic nucleus MCG-6-30-15 or the kiloHertz quasi periodic oscillations in Galactic neutron star systems can be correctly interpreted only making use of the peculiar properties of the space-time around compact objects. The importance of these observations relies on the possibility to probe the emission processes of the most violent and energetic astrophysical sources in the Universe and to study the properties of matter under extreme physical conditions.

Part of the research activity in High Energy Astrophysics at the Astronomical Observatory of Padova is focused on the development of models and numerical codes to study these phenomena using a fully relativistic approach. Recent work has been carried out to calculate the profiles of relativistic emission lines from accretion disks around supermassive black holes in Active Galactic Nuclei, adopting an original and numerically efficient method. A new project aimed at studying the evolution of the orbits and the fate of small bodies orbiting a black hole, that may be relevant for explaining the energy mechanism of flares in the galactic center, is also being undertaken.

Related work is also carried out to study the physical properties of Quasars and Active Galactic Nuclei and is presented under the Section Active Galaxies.

Past studies