Sung-Han Tsai (NTU/ASIAA); Ke-Jung Chen (ASIAA); Aaron Smith (MIT); Yi-Kuan Chiang (MIT)
The standard cosmological model (ΛCDM) predicts the existence of the cosmic web which composed of interconnecting galaxies and gases stretched out across the universe. However, due to the low-density gas , stars can not form inside this filamentary structure of cosmic web and lead to the difficult and elusive of observation. Theoretically, those filaments can emit the Lyα photons but if the only source of ionizing radiation is UV background, it is still too faint to directly observe. In our work, we use the cutting-edge cosmological simulation data, IllustrisTNG, to calculate the Lyα emission in the universe and compare it with recent observations. We also construct an all-sky distribution of Lyα intensity mapping to explore the structure of the cosmic web.