CGM observations in emission
Speaker: Haruka Kusakabe
Abstract:
The evolution of galaxies is directly linked to the gas reservoirs surrounding them, so-called, “the circum-galactic medium (CGM)”. Gas and metals are exchanged via inflows and outflows through the CGM, which is an interface between the interstellar medium (i.e., galaxy) and intergalactic medium (the rest of the Universe). The CGM has been studied with absorption lines imprinted in spectra of bright background quasars (tomography), but this method is limited to line of sight and cannot provide the 2D spatial distribution of the CGM. Recent sensitive, wide-FoV integral-field spectrographs (such as VLT/MUSE and Keck/KCWI) make it possible to individually detect the CGM in emission, which allows us to map the gas and metals around host galaxies. In this talk, I will review the recent progress in observations and understanding of hydrogen gas and metals around z>~2 galaxies, which are detected as extended Lyα emission (Lyα haloes) and metal-line haloes. I will also connect the CGM observations in emission and absorption and introduce comparisons with simulations.