Non-perturbative decay of the curvaton into Higgs

Who: Rose Lerner (Helsinki Institute of Physics (HIP))
When: Monday, September 17, 2012 at 14:15
Where: U49D

In an inflationary cosmology, the observed primoridal density perturbation could come from the quantum fluctuations of another light ‘curvaton’ field, rather than the inflaton. We investigate a simple model where the curvaton is coupled only to the Standard Model Higgs boson. In such case, one would expect a fast non-perturbative decay of the curvaton, so that the curvaton would not have time to build up the curvature perturbation. However, we find that, contrary to expectation, the curvaton decay may be delayed even down to electroweak symmetry breaking. This happens because of thermal corrections to the higgs mass due to the thermal background generated by the inflaton decay. As a consequence, it is possible to obtain the observed curvature perturbation for a wide range of parameters.