Abstract We explore a supergravity model based on the modified Kähler potential K = -3 (+ ^ - \, R R -. . \, (R R) ²) K ^ = - 3 ln Φ + Φ † - β R R ¯ - γ (R R ¯) 2, where Φ is a chiral superfield containing the dilaton and R R is the chiral curvature superfield. The quartic term - (R R) ² - γ (R R ¯) 2 ensures stabilization of the curvature sector, in line with recent proposals in modified supergravity, while the linear term - R R - β R R ¯ yields a dilaton-modulated contribution to the effective R² R 2 coefficient. As clarified via the superfield Legendre transform, the model is equivalent to Einstein supergravity coupled to three chiral superfields (Φ, S, T), yielding six physical scalars. Full stability requires both the curvature–sector stabilization (via γ) and a non-vanishing dilaton VEV. When the extra scalars are stabilized and = O (MP) ⟨ ϕ ⟩ = O (M P), the kinetic mixing is exponentially suppressed during inflation (Z e^- /6 Z ∝
R. Baghbani (Tue,) studied this question.