Mapping Extended Circumgalactic Lyα Nebulae Around Quasars With J-PAS — 

Circum-Galactic Medium (CGM) is the gas surrounding galaxies outside their disksand inside their virial radii. Lyman-alpha (Lyα) emission is one of the most important spectral features for probing the CGM at high redshifts, providing crucial insights into the formation and evolution of galaxies and their environments in the early Universe. This emission can trace outflows, inflows, and other processes that are key to understanding how galaxies interact with their surroundings. However, the origin of Lyα emission around quasars still under debate, particularly in terms of whether the emission arises primarily from photoionized gas, from cooling gas in the CGM, or from processes related to quasar-driven outflows. These different scenarios have profound implications for our understanding of galaxy formation and evolution, as they can shed light on feedback mechanisms, gas accretion, and the impact of quasars on their host galaxies. In this talk, I will present a study of extended Lyα emission around quasars at z>2 utilizing the capabilities of the Javalambre Physics of the Accelerating Universe Astrophysical Survey (J-PAS) with its 54 optical narrow-band filters over thousands of degrees. I will highlight our recent discovery of a massive Lyα nebula using J-PAS early data release, demonstrating the unique ability of J-PAS’s multi-band photometry to detect faint, extended structures, providing new perspectives on the dynamic relationship between quasars and their environments at high redshift.