Commission J2 Intergalactic Medium

Scientific Objectives

Commission J2 covers all thematics dealing with the physics of the Intergalactic Medium investigated with all approaches: observational, theoretical and numerical. The main topics can be listed under 4 research items:
1.  The structure of the Intergalactic Medium
     The Lyalpha forest in hydrogen and helium
     3D tomography of the IGM (in absorption and in fluorescent emission)
2. The ultra-violet metagalactic background
    Cosmic UV background
    Populations of galaxies and Active Galactic Nuclei
3. The interaction of galaxies and Active Galactic Nuclei and the IGM
    The Circumgalactic Medium and the extended gaseous environments of galaxies and AGN
    Feedback (metal absorption lines, winds and photonionization)
4. The Epoch of Reionization
    EoR 21 cm measurements
    Nature of the reionization sources 


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