| Date: |
September 9, 2008, 15:30 - 16:30 |
| Place: |
Seminar Room at IPMU Prefab. B, Kashiwa Campus of the University of Tokyo |
| Speaker: |
Mitsuru Kakizaki (Bonn University) |
| Title: |
Abundance of Thermal Relics in Non-standard Cosmological Scenarios
![[PDF]](/img/common/point04.gif)
|
| Abstract: |
We investigate the relic density of non-relativistic long-lived or
stable particles in non-standard cosmological scenarios. We derive
approximate solution for the relic density which accurately reproduce
numerical results when full thermal equilibrium is not achieved.
Assuming that thermally produced WIMPs account for the observed dark
matter energy density, we obtain the lower bound on the reheat
temperature, and constrain possible modifications of the Hubble
expansion rate. We also propose a new ansatz for the
thermally-averaged annihilation cross section of relic particles that
decouple semi-relativistically, and derive an approximate analytic
solution for their abundance. Some applications of such
semi-relativistically decoupled relics are discussed
|
