May 27, 14:15 in A315 (Friday Seminar)   

Andrea Ferrantelli (Helsinki)


Particle production and rapid thermalization after MSSM inflation

In the model of MSSM inflation, the inflaton is a D-flat direction in the scalar potential, consisting of the supersymmetric partners of quarks and leptons. Since its couplings to matter are known via the Minimal Supersymmetric Standard Model (MSSM) interactions, it is possible to study the particle production at the end of inflation in great detail, and to track the thermal history of the universe accordingly. This is a striking difference with respect to inflationary models where the inflaton is an arbitrary gauge singlet. In this talk (which is based on arXiv:1103.2123 [hep-ph]), I will address the production of matter and thermalization via the decay of the LLe inflaton, namely of a gauge invariant combination of sleptons. After the end of inflation, the inflaton oscillates coherently about the minimum of its potential, producing gauge/gaugino and (s)lepton quanta, which then decay very quickly to (s)quarks. After about 100 oscillations - albeit within one Hubble time - the amplitude of inflaton oscillations becomes sufficiently small, and all of the degrees of freedom will thermalize. This provides by far the most efficient reheating of the universe with the observed degrees of freedom.