***********************************************************
OATS-UNI/TS SEMINAR
***********************************************************
Speaker: James Bolton (Univ. of Nottingham, UK)
Title: Reionisation via the Lyman-alpha line
Date: Wednesday, April 17th, 2013
Time: 11:30
Venue: Villa Bazzoni
***********************************************************
Abstract: The first luminous objects to form in the Universe produced
ultra-violet photons which photo-ionised and heated the previously
cold and neutral intergalactic medium (IGM). Observing the impact of
the reionisation era on the IGM therefore provides us with an indirect
probe of the formation and evolution of the first galaxies. Low
frequency radio observations of the high redshift Universe will
provide an exciting new window into this important epoch in the near
future, but in the present the Lyman-alpha line (both in absorption
and emission) can also inform us about the physical state of the high
redshift IGM. In this talk I will briefly review existing
observational constraints on the reionisation era, before going on to
discuss new developments arising from observations of Lyman-alpha
absorption around bright quasars at z=6-7 and the abundance of
Lyman-alpha emitting galaxies approaching z=7. These measurements may
be used to test existing theoretical models for reionisation, and can
yield fresh insight into the timing of reionisation as well the nature
of the first sources of light in the early Universe.
***********************************************************
Contact: Matteo Viel (OATs)