The researchers in this group work on a coherent description of the formation and evolution of galaxies in the Universe, from the Milky Way to the galaxies observed at remote ages. They carry out their expertise in advanced observations from the ground and space, from X-rays to radio waves, and in theoretical models for interpreting these data. The development and availability to the astrophysical community of evolutionary codes of spectral synthesis of galaxies and codes for astronomical image analysis constitute the group's strong points.
In order to characterize their individual and collective properties, galaxies are studied according to a wide variety of approaches: the spectral analysis of their constituents: stars, gas and dust; automatic measurement of their flux and shape; the deciphering of their internal dynamic equilibrium; the mapping of intra-cluster gas. Groups and clusters of galaxies are privileged places to evaluate the role of interactions and the influence of dark matter halos on the internal properties of galaxies. Energy phenomena such as bursts of star formation, radiogalaxies and their relativistic jets are also examined in detail.