ACP Seminar (Astronomy - Cosmology - Particle Physics)

Speaker: Kohei Kamada (DESY)
Title: Spontaneous Cogenesis from the MSSM Flat Direction as the Origin of Matter and Dark Matter
Date (JST): Wed, Mar 21, 2012, 13:30 - 14:30
Place: Seminar Room B
Related File: 605.pdf
Abstract: The observational relation between the density of baryon and dark matter in the Universe is one of the most difficult problems to solve in modern cosmology. We discuss a scenario that explains this relation by combining the asymmetric dark matter scenario and the spontaneous baryogenesis associated with the flat direction in the supersymmetric standard model. A part of baryon asymmetry is transferred to charge asymmetry that dark matter carries, if a symmetry violating interaction that works at high temperature breaks not only B - L symmetry but also the symmetry that dark matter carries simultaneously. In this case, the present number density of baryon and dark matter can be same order if the symmetric part of dark matter annihilates sufficiently. Moreover, the baryon number density can be enhanced as compared to that of dark matter if another B - L violating interaction is still in thermal equilibrium after the spontaneous genesis of dark matter, which accommodates a TeV scale asymmetric dark matter model.