Hybrid inflation in quasiminimal supergravity with monotonic inflationary potential

We show how supersymmetric hybrid inflation with scalar spectral index $n_{\mathrm{s}}\simeq 0.96–0.97$ is realized in the context of quasiminimal supergravity if we insist that the inflationary potential not exhibit any local extrema. We also address the problem of the initial conditions for both monotonic and nonmonotonic inflationary potentials.

Figure 1

The exact value of $\sigma V_F^{\prime }/({\kappa }^2{M}^4)$ during inflation with the radiative corrections included as a function of the absolute value of the field $\sigma$ for $\alpha =0.01$ and $\gamma =0.24743$, 0.25, 0.30.

Figure 2

The values of $\beta =\alpha$, $\kappa$, $|{\sigma }_{*}|$, and $M$ as functions of $n_{\mathrm{s}}$ for $\gamma =0.25$.

Figure 3

The number $N_{*}$ of $e$-foldings as a function of $\beta$ with $n_{\mathrm{s}}=0.96$ for $\gamma =0.25$, 0.275, 0.30.

Figure 4

The number $N_{*}$ of $e$-foldings as a function of $\beta$ with $n_{\mathrm{s}}=0.97$ for $\gamma =0.25$, 0.30, 0.35, 0.40, 0.45.

Figure 5

The evolution of the energy density $\rho$ as a function of $N_{\exp }$ for $n_{\mathrm{s}}=0.96$ and $\gamma =0.25$ with an early inflationary stage.

Figure 6

The evolution of the fields $\sigma$ and $\zeta$ as functions of $N_{\exp }$ for $n_{\mathrm{s}}=0.96$ and $\gamma =0.25$ with an early inflationary stage.

Figure 7

The evolution of the field $\phi$ as a function of $N_{\exp }$ for $n_{\mathrm{s}}=0.96$ and $\gamma =0.25$ with an early inflationary stage.

Figure 8

The evolution of the energy density $\rho$ as a function of $N_{\exp }$ in the scenario with $\beta =1/150$, $x_{*}=0.5$, and $\kappa =0.01$ (nonmonotonic $V_{\inf }$) with an early inflationary stage.

Figure 9

The evolution of the fields $\sigma$, $\phi$, and ${\overline{\phi }}_1$ as functions of $N_{\exp }$ in the scenario with $\beta =1/150$, $x_{*}=0.5$, and $\kappa =0.01$ (nonmonotonic $V_{\inf }$) with an early inflationary stage.

Figure 10

The evolution of the fields $\sigma$, $\phi$, ${\overline{\phi }}_1$, and $\zeta$ as functions of $N_{\exp }$ for $n_{\mathrm{s}}=0.96$ and $\gamma =0.25$ without an early inflationary stage.

Figure 11

The evolution of the fields $\sigma$, $\phi$, and ${\overline{\phi }}_1$ as functions of $N_{\exp }$ in the scenario with $\beta =1/150$, $x_{*}=0.5$, and $\kappa =0.01$ (nonmonotonic $V_{\inf }$) without an early inflationary stage.