Our cosmological model predicts that most of the matter in the universe is distributed in a network of filaments - the Cosmic Web – in which galaxies form and evolve. Because most of this material is too diffuse to form stars, its direct imaging has remained elusive for several decades leaving fundamental questions still open, including: what are the morphological and kinematical properties of the Cosmic Web on both small (kpc) and large (Mpc) scales? How do galaxies get their gas from the Cosmic Web?
The CosmicWeb program tackle these questions with an innovative method and technology that allows us to directly detect in emission the gaseous Cosmic Web before the peak of galaxy formation, when the universe is less than 3 billion years old: using bright quasars and galaxies as “cosmic flashlights” to make the gas “fluorescently” glow.
The Program is divided into two, interconnected, main Projects. Project 1 aims at the detection of Cosmic filaments on large scales (Scientific Objective, SO, 1), the study of their relation with galaxies (SO2) and the comparison with models to constrain dark matter properties (SO3). Project 2 aims at the high-spatial resolution study of filaments using non resonant lines such Hydrogen H-alpha in order to reveal their small scale distribution (SO4) and their kinematics compared with galaxies (SO5) to inform new CGM models (SO6). The success of these SOs require: i) deep MUSE observations in order to reveal Cosmic filaments in Ly-alpha emission on large scales, ii) multi wavelength information to detect and study the associated galaxy properties, iii) JWST observation to detect H-alpha emission at high-spatial resolution, and, iv) numerical models on both large and small scales (with different dark matter properties).