Braneworld Inflation in Supergravity with a Shift Symmetric Kähler Potential

We propose a new solution to the η-problem in supergravity using a shift symmetric Kähler potential in the context of the Randall–Sundrum type II model. We focus on a F-term supergravity inflation with a minimal Kähler potential taking into account the radiative corrections. The slow-roll conditions are ensured by the shift symmetry where a very small value of η(η?1) is obtained. In this context, we derive all known spectrum inflationary parameters which are widely consistent with Planck 2015 data for a particular choice of brane tension and coupling constant values. A suitable observational central value of n _s=0.96 is also obtained in the case of minimal Kähler potential.     

Reheating Temperature from D-Term Cosmological Inflation Braneworld

The D-term inflation in supergravity, in the braneworld Randall Sundrum II (RSII) context, has been proposed to solve some problems related to the four-dimensional inflation model. That scenario is based on a modification of the Friedmann equation by the addition of the fifth dimension, which corresponds to an energy, called brane tension λ. Therefore, we propose the investigation of the brane effect on the reheating epoch. In this context, we have analyzed the process of reheating and focused on the variation of the temperature value T_re. We found that it depends on all parameters, and the value found is in the range T_re ∼ (7.5 × 10⁸−8 × 10¹⁰) GeV, which is consistent with the thermal leptogenesis (T_re ≥ 10⁸ GeV).