Speaker
Dr
Sebastiano Cantalupo
(UCSC)
Description
I will present the result of a an ongoing, successful program that uses a new approach to directly detect and study cosmic gas in the early Universe: the key idea is to use an external ``source of illumination’’, a bright quasar, to light up with fluorescent Lyα emission dark, proto- galactic clouds and dense streams around galaxies in a large cosmological volume. In the first part of the talk, I will discuss our pilot project based on deep narrow-band imaging on VLT /FORS centered on a z=2.4 hyper-luminous quasar: how we identified and characterized the physical properties of the first sample of high-redshift, “dark” galaxy candidates. In the second part of the talk, I will present the detection of fluorescent emission from the Circumgalactic Medium of star forming galaxies and very recent, spectacular results obtained with Keck/LRIS of the detection of hundred-kpc scale filaments surrounding bright quasars.
