Axion lumps in the Cosmic Microwave Background

TYPEAstrophysics Seminar
Speaker:Robert Reischke
Time:14:30 - 15:30
Location:Lidow 620

The particle nature of dark matter is an unresolved issue. One candidate receiving a lot of attention recently is the Axion. They are produced at the Peccei-Quinn scale by different mechanisms in the early Universe.  If they are produced after inflation the Axion field will have additional random fluctuation of the size of causally connected region at the Peccei-Quinn symmetry breaking. These fluctuations can leave observable signatures in the Cosmic Microwave Background (CMB) depending on the mass of the axion.

In this talk I will briefly review dark matter from a cosmological angle, followed by a brief introduction of axions. I will finish showing how CMB data can be used to constrain the mass of Axions produced in this post-inflationary scenario.