Astrophysics Research | School of Physical Sciences
Astrophysics Research Group Members: Dr. Masha Chernyakova
The DCU Astrophysics Group focuses on high-energy astrophysics. It works in close collaboration with Irish and international astrophysical research groups – including Dublin Institute for Advanced Studies (DIAS), University College Dublin (UCD), ISDC (Switzerland) and APC (France).
The focus of high–energy astrophysics is X-ray and gamma-ray emission from cosmic sources. It is produced by extremely hot objects (with temperatures greater than one million degrees – 200 times hotter than the surface temperature of our sun), or through highly energetic non-thermal phenomena.
A new generation of high-energy gamma-ray telescopes is revealing the universe in its most extreme and non-thermal form. The new objects discovered by these telescopes include binary systems in which a neutron star or a black hole orbits a massive star. Despite the fact that the total number of binary systems in the Universe is huge, the number of these systems observed at gamma-ray energies is extremely small. Up to now, it has not been clear which conditions are needed to be fulfilled to allow efficient acceleration of particles responsible for the observed emission. The focus of the DCU research team is to combine theoretical modelling with experimental observation to address this issue.
Supermassive black hole, Sagittarius A*(Sgr A*), located in the very centre of our Galaxy is also known to radiate up to very high energies. Surprisingly, despite its mass, Sgr A* is presently an extremely weak emitter at nearly all wavelengths. Using X-ray, GeV and TeV data our group is investigating the recent past behaviour of Sgr A* in order to find out if the present quiet state of emission is a normal condition for Sgr A* or if this source undergoes periods of significantly higher activity, which would have important implications for cosmic ray emission and the dynamics of our whole Galaxy.
The Astrophysics Research Group is in a collaboration with the Integral Data Science Centre in Geneva and with a group at the AstroParticule et Cosmologie in Paris.