Speaker
Mr
Koji Ishiwata
(Department of Physics,Tohoku University)
Description
We consider supersymmetric model with right-handed (s)neutrinos where
the neutrino masses are purely Dirac type. We discuss cosmology based
on such a scenario, paying particular attention to the case that the
gravitino is the LSP while the right-handed sneutrino is the next-LSP.
It will be shown that the cosmological constraints on the
gravitino-LSP scenario (in particular, those from the big-bang
nucleosynthesis) are drastically relaxed in such a case. We will also
consider the implication of such scenario to the structure formation.
Author
Mr
Koji Ishiwata
(Department of Physics,Tohoku University)
Co-authors
Dr
Shigeki Matsumoto
(International Advanced Research and Education Organization,Tohoku University)
Prof.
Takeo Moroi
(Department of Physics,Tohoku University)
