1208.2496 (Kiwoon Choi et al.)

Dark radiation and small-scale structure problems with decaying particles    [PDF]

Kiwoon Choi, Ki-Young Choi, Chang Sub Shin

Although the standard {\Lambda}CDM model describes the cosmic microwave background radiation and the large scale structure of the Universe with great success, it has some tensions with observations in the effective number of neutrino species (dark radiation) and the number of small scale structures (overabundance problem). Here we propose a scenario which can relax both tensions through late decays of heavy particle. Supersymmetric axion model is found to be a natural set up for this scenario.

View original: http://arxiv.org/abs/1208.2496