Joint Astrophysics Colloquium

Joint Astrophysics Seminar

Cosmic Reionization

Ue-Li Pen

CITA

The first luminous objects which reionized the universe are constrained to have formed at redshifts 6<z<20. I will report on theoretical and observational constraints, and progress through simulations and observations. Two types of targets may be observable in the near future: the Stromgren spheres around known SDSS quasars, and the more typical reionization bubbles surrounding protogalaxies.