Keywords:
Clusters of Galaxies
Plasma Astrophysics
Radio galaxies
Radioastronomical techniques
- Field of research n. 1 -
Radio emission is a short-lived phenomenon (10^7-10^8 yr) if
compared to the typical age of galaxies (10^10 yr). It is unclear
what are the ingredients necessary to produce relativistic
electrons and magnetic field then producing synchrotron radiation.
Giver the relatively quick evolution of the properties of radio
sources, very important information comes from the objects in which
the radio emission is in its early phase, coming from a region
close to the nucleus of the host galaxy, and with typical ages of
the order of thousand years. The investigation of these young and
then small objects is a very important subject in the study of the
origin of the radiated energy and on the properties of the ambient
medium where the radio plasma is expanding.
- Field of research n. 2-
Clusters of galaxies allow the investigation of a variety of
astrophysical phenomena. Radio emission provides information on the
nuclear activity of the galaxies within the cluster and allow the
study of the interaction of the relativistic plasma with the hot
ionized gas which is found in the intergalactic space and
represents the main contribution to the visible mass of the cluster
itself. Furthermore, the diffuse emission occasionally found,
without any association with a given galaxy, provides very
important information on the dynamical history of accretion of new
galaxies to the cluster, as captured by gravitational potential
well of the cluster.
- Field of research n. 3-
The radio emission comes from magnetized relativistic plasma
produced in the nuclear region of the host galaxy and then
accelerated to velocities close to the speed of light towards the
interstellar medium and then of the intergalactic medium. The
interaction with such ambient media affects the properties of the
synchrotron emission and allows to derive information on the
physical condition of both the relativistic plasma and ambient
media themselves.