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The two young star disks in the central parsec of the galaxy: properties, dynamics and formation
We report the definite spectroscopic identification of 40 OB supergiants, giants and main sequence stars in the central parsec of the Galaxy. Detection of their absorption lines have become possible
A gas cloud on its way towards the supermassive black hole at the Galactic Centre
The presence of a dense gas cloud approximately three times the mass of Earth that is falling into the accretion zone of Sagittarius A*, a compact radio source at the Galactic Centre, is reported.
Massive black hole binary mergers within subparsec scale gas discs
We study the efficiency and dynamics of supermassive black hole binary mergers driven by angular momentum loss to small-scale gas discs. Such binaries form after major galaxy mergers, but their fate
Dissecting X-ray–Emitting Gas Around the Center of Our Galaxy
X-ray observations of the center of the Galaxy reveal the interplay between the massive black hole there and its surroundings, and provide important constraints for models of the prevalent radiatively inefficient accretion state.
Limiting eccentricity of subparsec massive black hole binaries surrounded by self-gravitating gas discs
We study the dynamics of supermassive black hole binaries embedded in circumbinary gaseous discs, with the SPH code GADGET-2. The sub-parsec binary (of total mass M and mass ratio q = 1/3) has
Science with the Cherenkov Telescope Array
The Cherenkov Telescope Array, CTA, will be the major global observatory for very high energy gamma-ray astronomy over the next decade and beyond. The scientific potential of CTA is extremely broad:
Galactic Centre stellar winds and Sgr A* accretion
This work suggests that, averaged over time-scales of hundreds to thousands of years, the radiative and mechanical luminosity of Sgr A ∗ may be substantially higher than it is in its current state.
Variable accretion and emission from the stellar winds in the Galactic Centre
Numerical simulations of stellar wind dynamics in the central parsec of the Galactic Centre are presented, studying in particular the accretion of gas on to Sgr A ∗ , the supermassive black hole, and the possibility of constraining the total mass-loss rate of the ‘slow-wind stars’ using near infrared observations of gas in thecentral few arcseconds is shown.
Evolution of binary black holes in self gravitating discs. Dissecting the torques
Context. Massive black hole binaries, formed in galaxy mergers, are expected to evolve in dense circumbinary discs. Understanding of the disc-binary coupled dynamics is vital to assess both t he
Simulations of star formation in a gaseous disc around Sgr A* - A failed active galactic nucleus
We numerically model fragmentation of a gravitationally unstable gaseous disc under conditions that may be appropriate for the formation of the young massive stars observed in the central parsec of