ACP Seminar (Astronomy - Cosmology - Particle Physics)

Speaker: Kazunori Nakayama (U. Tokyo)
Title: Cosmological Aspects of Inflation in a Supersymmetric Axion Model
Date (JST): Wed, Apr 18, 2012, 13:30 - 14:30
Place: Seminar Room A
Abstract: We show that the hybrid inflation is naturally realized in the framework of a supersymmetric axion model, which is consistent with the WMAP observation if the Peccei-Quinn symmetry breaking scale is around 10^{15}GeV. By solving the post inflationary scalar dynamics, it is found that the scalar partner of the axion, saxion, oscillates with large amplitude and its decay produces a huge entropy and dilutes the axion. As a result, the axion coherent oscillation can be the dominant component of the dark matter in the Universe. Cosmological gravitino and axino problems are solved.