From star-forming galaxies to AGN: the global HI content from a stacking experiment

We study the atomic neutral hydrogen (HI) content of \(\sim\)1600 galaxies up to \(z \sim 0.1\) using stacking techniques. The observations were carried out with the Westerbork Synthesis Radio Telescope (WSRT) in the area of the SDSS South Galactic Cap (SSGC), where we selected a galaxy sample from the SDSS spectroscopic catalog. Multi-wavelength information is provided by SDSS, NVSS, GALEX, and WISE. We use the collected information to study HI trends with color, star-forming, and active galactic nuclei (AGN) properties. Using NUV-r colors, galaxies are divided into blue cloud, green valley and red sequence galaxies. As expected based on previous observations, we detect HI in green valley objects with lower amounts of HI than blue galaxies, while stacking only produces a 3-\(\sigma\) upper limit for red galaxies with M\(_{\rm HI}\) \(