Lights in the cosmic dark ages
Monday Dec. 8th, at 12:30am, 3E
XueLei Chen (ITP)

Abstract: I will talk about two different topics.  In the first part, I will discuss the physics of spin temperature evolution of the neutral hydrogen before reionization and its implication on the 21 cm observation of the cosmic dark ages  (based on astro-ph/0303395). In the second part, I will discuss particle decay as a possible alternative explanation for the high optical depth  observed by WMAP (based on astro-ph/0110473).