At high redshift most of the baryons reside outside galaxies, in an intricated network of sheets, filaments and knots, also known as the Cosmic Web. The direct detection of this large-scale gas structures has been elusive, but advancements in this field are slowly unveiling the intergalactic gas.
The exquisite sensitivity of new integral field spectrograph (e.g., MUSE on VLT/ESO) together with the recent discovery of Enormous (>200 kpc) Lyman-Alpha Nebulae (ELAN) around radio-quiet z~2-3 quasars have fostered the study of this circum/inter-galactic gas in emission around individual systems on very large scales.
Extended Lyman-Alpha emission is now routinely detected around high-z quasars, and it is usually explained as powered by the ionizing radiation of these sources.
In this talk the speaker will present a census of z~2-3 quasar fields using the narrow-band and IFU technique with the aim to determine the frequency of the ELAN phenomenon, as well as to study the size, luminosity, covering factor, and the gas physical properties of the average Lyman-alpha nebula around quasars and their evolution through cosmic time.
In particular, the speaker will show the results of the QSO MUSEUM survey (Quasar Snapshot Observations with MUse: Searching for Extended Ultraviolet eMission), which comprises 61 z~3 quasars observed with the MUSE/VLT instrument, and which suggests that Lyman-alpha could be used to trace the inspiraling motions of the cool circum-galactic medium, predicted to take place on hundreds of kpc within massive halos. The speaker will conclude by showing the direct study of large-scale gas in emission around a z~3 physical quasar pair.
BIO
Dr. Fabrizio Arrigoni Battaia got both his Bachelor degree in physics and Master degree in Physics and Space Physics at the Università Milano-Bicocca (Milan, Italy); he got his PhD in astrophysics at the Max-Planck-Institute for Astronomy (MPIA) and Heidelberg University (Germany).
2015.11 - 2018.10, ESO research fellow, at the European Southern Observatory (ESO) headquarters in Garching (Germany); 2018.11 - 2019.10, MPA research fellow, at the Max-Planck-Institute for Astrophysics (MPA) in Garching (Germany); 2019.11 - now, tenure-track scientific staff at the Max-Planck-Institute for Astrophysics (MPA) in Garching (Germany).
Host: Zheng Cai
