Dr. Dan Stern
Jet Propulsion
Laboratory (JPL)
Title:
High-Redshift Galaxies and the Epoch
of Reionization
Date:
Time:
416 Phy/Geo
The observation of
galaxy and quasar light emitted when the universe was less than a billion years
old has opened a window for spectroscopic exploration of the early history of
the intergalactic medium. I will review theoretical and observational results
on the early reionization history of the
universe, with an emphasis on recent constraints derived from high-redshift Lyman-alpha emitting galaxies.
Surprisingly, there appears to be little change in the luminosity function of
Lyman-alpha emitting galaxies between z~5.7 and z~6.5. Since z~6.5 lays beyond the putative epoch of reionization when the damping wings
of the neutral hydrogen IGM is capable of severely attenuating Lyman-alpha
emission, these results suggest that the IGM may remain largely ionized from
the local universe out to z~6.5.