A $U(1)_R$ inspired inflation model in no-scale Supergravity

Understand

We consider a cosmological inflation scenario based on a no-scale supergravity sector with $U(1)_R$ symmetry.

• It is shown that a tree level $U(1)_R$ symmetric superpotential alone does not lead to a slowly rolling scalar potential.
• A deformation of this tree level superpotential by including an explicit $R$ symmetry breaking term beyond the renomalizable level is proposed.
• The resulting potential is found to be similar (but not exactly the same) to the one in Starobinsky inflation model.