Conveners
Hydrogen in the IGM
- Avery Meiksin (The University of Edinburgh)
Hydrogen in the IGM
- There are no conveners in this block
Hydrogen in the IGM
- There are no conveners in this block
Hydrogen in the IGM
- There are no conveners in this block
Prof.
John O'Meara
(Saint Michael's College)
24/06/2013, 09:30
Invited Talk
Mr
Marcel Neeleman
(UCSD)
24/06/2013, 10:10
Contributed Talk
The study of the high redshift universe through quasar absorption lines allows us to measure in great detail the properties of the gas that is responsible for the absorption. Damped Lyα systems, DLAs, the largest of these absorbers, are intimately linked to the predecessors of modern-day galaxies, and their study provide insight into how galaxies form and evolve. In this talk, I will review...
Mr
Ali Rahmati
(Leiden Observatory)
24/06/2013, 10:40
Contributed Talk
In this talk, I will show that cosmological simulations of galaxy formation that match the cosmic star formation history are also capable of reproducing the observed HI distribution when they are combined with accurate radiative transfer calculations. I will discuss the impact of different ionizing processes (i.e., the UV background, recombination radiation, collisional ionization and local...
Dr
Michele Fumagalli
(Carnegie Observatories/Princeton University)
24/06/2013, 11:40
Invited Talk
Already from the first quasar surveys, it became evident that Lyman limit systems (LLSs) differ from the Lyα forest and are likely associated to galaxies. Recently, this idea has received renewed attention because of the proposed connection between LLSs and the so-called "cold streams" that are postulated to feed star forming galaxies at z>2. In this talk, I will present results from a new...
Dr
Khee-Gan Lee
(MPIA)
24/06/2013, 12:20
Contributed Talk
The BOSS Lyα forest survey is obtaining Lyα forest sightlines for over 160,000 QSOs at z>2. While the signal-to-noise and resolution is moderate, I will show that it is possible to obtain information on the IGM temperature-density relation by measuring the flux PDF from the BOSS Lyα forest data. I will discuss new methods for continuum-estimation, noise- and metal-modelling that allow us to...
Dr
Sebastiano Cantalupo
(UCSC)
25/06/2013, 16:00
Invited Talk
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...
Dr
Marc Rafelski
(IPAC (Caltech))
25/06/2013, 16:40
Contributed Talk
We present chemical abundance measurements for damped Lyα systems (DLAs) at z>4, which show a clear decrease in the metallicity of DLAs with increasing redshift. We find a possible break in the metallicity evolution of DLAs at z>4.7, and showcase our latest results using new Keck ESI and Magellan FIRE spectra. This break may represent a transition in the nature of DLAs, where high redshift...
Dr
George Becker
(University of Cambridge)
27/06/2013, 14:15
Invited Talk
Reconciling our current constraints on hydrogen reionization with what we know about high-redshift galaxy populations points to interesting galaxy physics at early times. For example, in order to emit enough ionizing photons to complete reionization by z=6, it appears that faint sources must make a larger than expected contribution to the ionizing budget at z > 6, or else reionization galaxies...
Ms
Elisa Boera
(Swinburne University)
27/06/2013, 14:55
Contributed Talk
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...
Mr
Alberto Rorai
(Max Planck Institute for Astronomy - Heidelberg)
27/06/2013, 15:25
Contributed Talk
The small scale structure of the IGM, quantified by the Jeans filtering scale, has fundamental cosmological implications. On the one hand, it provides a thermal record of the heat injected by UV photons during cosmic reionization events, and its value thus constrains the thermal and reionization history of the Universe. On the other hand, it sets the minimum mass scale for gravitational...
