Speaker
Ms
Elisa Boera
(Swinburne University)
Description
The HeII reionization is expected to leave a “footprint” on the thermal history of the IGM: a peak in the temperature evolution at the mean density. So far no clear evidence for this mark has been found and recently it has been suggested that new volumetric heating processes, from blazar emission, could dominate the photo-heating at z<3. These processes would obscure the peak due to the HeII reionization preventing any constraint on this event. We present an extension of the IGM temperature measurements down to the optical limit of the HI Lyα forest at z≃1.5. This is the regime where the different models of thermal histories diverge most strongly. Applying the curvature method, we investigated the thermal history of the IGM at z<3 with precision comparable to the higher redshifts results. We will show the measurements obtained and we will discuss their consistency with the different heating models.
