IUCAA Brochure 2024

Intergalactic medium IUCAA is leading major observational campaigns, in collaboration with international scientists, to map the distribution of very diffuse, invisible gas surrounding galaxies and clusters of galaxies and characterize their physical properties. Using large quantities of spectroscopic data, the team has recently reported the detection of neutral gas and heavy elements surrounding clusters of galaxies and mapped their spatial distributions out to several million light years for Galaxies are the building blocks of the universe. However, more than 90%of all the ordinarymatter in the universe resides outside galaxies in a tenuous medium called the intergalactic medium (IGM). Galaxies attract and accumulate gas from the IGM to grow in mass and size. On the other hand, large-scale winds from galaxies also eject gas, including the heavy elements (e.g., Carbon, Oxygen and Nitrogen) produced inside galaxies, into the IGM. IUCAA researchers are involved in understanding how such interactions between galaxies and the IGMshape galactic evolution. the first time. The teamhas also produced statistical maps on the distribution of neutral hydrogen surrounding low-redshift galaxies with the largest-ever sample size. Using state-of-the- art integral-field spectroscopy, they are also studying the connection(s) between very distant galaxies and the gas around themwhen the universewas only 15%of its current age.