The details of the physics of baryons in galaxies is still unclear. If the hierarchical growth  scenario of large structures and dark matter halos is largely accepted many questions remain about the stars, gas and dust content of galaxies throughout the age of the Universe. My research focuses on the question of the reciprocal influence (power / feedback) of black holes and their host galaxy. For this, I try to probe the contents and properties of molecular gas in galaxies that présent evidences of feedback. Best example are central cluster galaxies (BCGs) or radio galaxies in the nearby Universe. I  also observe the very distant galaxies , that are the first structures grown by gas accretion and/or galaxy fusion  in the universe.

The star formation efficiency  in galaxies depends both on a small scale (microphysics: heating vs. cooling) and large-scale properties (morphology and dynamics of interactions with the environment: stellar winds, radio jets, mergers). With instruments like ALMA and NOEMA, the next decade promises great advances by mapping the vélocity field and excitation state of the bulk of the matter that precedes star formation.

Keywords: Galaxies: Formation and Evolution, clusters of galaxies, cooling Flows, AGN-Feedback, High-redshift. Observations: millimeter-submillimeter, ALMA, IRAM-30m, NOEMA SMA. Molecular gas, excitation