***********************************************************
OATS-DAUT SEMINAR
***********************************************************
Speaker: Sebastiano Cantalupo (IoA, Cambridge, UK)
Title: The bright Ly-alpha side of the high-redshift Intergalactic Medium
Date: Wednesday, October 6th, 2010
Time: 15:00
Venue: Villa Bazzoni
***********************************************************
Abstract:
The analysis of absorption systems in the spectra of high-z QSOs has represented for several decades the only practical way to study the Intergalactic Medium (IGM). Although very powerful, this method has several limitations. For instance, it is almost always one-dimensional. In this talk, I will discuss an alternative approach: the detection and study of the IGM in Ly-alpha emission rather than in absorption. In the first part of the talk, I will show how to model this emission at z~3 combining hydro-simulations and radiative transfer (RT) methods. The results of the model have been used to observe the IGM and proto-galactic clouds illuminated by a quasar at z~3 with different observational campaigns. I will discuss current results and future surveys with the new Integral Field Unit instrument MUSE at VLT. In the second part of the talk, I will extend the discussion to the Reionization epoch, showing how the IGM Ly-alpha emission produced within quasar ionization fronts can be used to directly map neutral hydrogen in a "tomographic" way (like future 21-cm surveys) with current optical/near-infrared facilities. I will present the predictions obtained with a new adaptive RT model, RADAMESH, able to resolve the small scales of the quasar ionization fronts within a large cosmological simulation. The detection of this Ly-alpha emission can shed new light on the reionization history, the age and the emission properties of the highest-redshift quasars.
***********************************************************
contact: Valentina D'Odorico (OATS)