Mapping the Multi-component Circumgalactic Medium: Insights from Extremely Deep MUSE Observations


Galaxies form, grow and evolve by exchanging gas with their environment. Information about the flow of gas in and out of galaxies is encoded in their circumgalactic medium (CGM). Studying the CGM is therefore crucial for testing modern theories of galaxy evolution. However, observing the CGM has been challenging due to its extreme faintness.

In this talk, I will present our recent efforts with the VLT-MUSE instrument to map the emission from the CGM or even the intergalactic medium (IGM). Using the exquisite MUSE deep-field data, our observations reveal different physical processes on scales of tens to hundreds of kiloparsecs. My key findings include: (1) An anisotropic MgII emission out to 15 kpc around z~1 galaxies, providing compelling evidence for bi-polar galactic outflows. (2) An average blueshift in the Lyα line out to 70 kpc, suggesting the existence of large-scale gas inflows. (3) The extended Lyα emission out to hundreds of kpc, marking a significant advance in our understanding of the IGM. This talk will end with a preview of our ongoing simulation efforts to reproduce the observed large-scale 3D behaviour of the Lyα line.

Dr. Yucheng Guo (郭昱程), Centre de Recherche Astrophysique de Lyon (CRAL), France
KIAA Shu Qi meeting room
Tuesday, March 5, 2024 - 1:30PM to Tuesday, March 5, 2024 - 2:30PM