862 research outputs found
Globular cluster-massive black hole interactions in galactic centers
Many, if not all, galaxies host massive compact objects at their centers.
They are present as singularities (super massive black holes) or high density
star clusters (nuclear tar clusters). In some cases they coexist, and interact
more or less strongly. In this short paper I will talk of the 'merger' globular
cluster scenario, which has been shown in the past to be an explanation of the
substantial mass accumulation in galactic centers. In particular, I will
present the many astrophysical implications of such scenario pointing the
attention on the mutual feedback of orbitally decaying globular clusters with
massive and super massive black holes.Comment: 4 pages, 1 fiugre. Presented at the MODEST 16/Cosmic Lab conference
in Bologna, Italy, April 18-22 2016. To be pusblshed in Mem. S.A.It.
Conference Serie
Evolution of the Globular Cluster System in a Triaxial Galaxy
Dynamical friction and tidal disruption are effective mechanisms of evolution
of globular cluster systems, especially in non-axysimmetric galaxies with a
central compact nucleus. With a semi-analytical approach based on the knowledge
of the dependence of the dynamical friction and tidal disruption effects on the
relevant parameters, we are able to follow the time evolution of the globular
cluster system in a model of a triaxial galaxy and give its observable
properties to compare with observational data.
An important result is that the flatter distribution of the globular cluster
system relatively to that of the stellar bulge, as observed in many galaxies,
can be explained by the evolution of the globular cluster system, starting from
the same density profile.Comment: 9 pages, including 7 eps figures; latex file using standard MNRAS
style file. Paper submitted to MNRA
Star Clusters and Super Massive Black Holes: High Velocity Stars Production
One possible origin of high velocity stars in the Galaxy is that they are the
product of the interaction of binary systems and supermassive black holes. We
investigate a new production channel of high velocity stars as due to the close
interaction between a star cluster and supermassive black holes in galactic
centres. The high velocity acquired by some stars of the cluster comes from
combined effect of extraction of their gravitational binding energy and from
the slingshot due to the interaction with the black holes. Stars could reach a
velocity sufficient to travel in the halo and even overcome the galactic
potential well, while some of them are just stripped from the cluster and start
orbiting around the galactic centre.Comment: 2 pages, 1 figure. Presented at the MODEST 16/Cosmic Lab conference
in Bologna, Italy, April 18-22 2016. To be pusblshed in Mem. S.A.It.
Conference Serie
- …