0.1 0.15 0.2 0.25 0.3 x 10 -4 0.925 0.95 0.975 1 n$_{s}$ H m $^{φ}$=60 GeV m $^{φ}$=120 GeV m $^{φ}$=280 GeV m $^{φ}$=440 GeV FIG. 8: n$_{s}$ is plotted as a function of δ$_{H}$ for different values of m$_{φ}$ . The 2 σ region for δ$_{H}$ is shown by the blue horizontal band and the 2 σ allowed region of n$_{s}$ is shown by the vertical green band. The 1 σ allowed region of n$_{s}$ is within the solid vertical lines. We choose λ = 1 [90]. 50, provided that the universe is immediately thermalized after the end of inflation [159, 160]. We note that reheating after MSSM inflation is very fast, due to gauge couplings of the in- flaton to gauge/gaugino fields, and results in a radiation-dominated universe within few Hubble times after the end of inflation [87, 88]. A remarkable property of MSSM inflation, which is due to inflation occurring near a point of inflection, is that it can give rise to a wide range of scalar spectral index. This is in clear distinction with other models (for example, chaotic inflation, hybrid inflation, natural inflation, etc.) and makes the model very robust. Indeed it can yield a spectral index within the whole 2 σ allowed range by 5-year WMAP data 0 . 934 ≤ n$_{s}$ ≤ 0 . 988. Note that for α 2 = 0, Eqs. (326,327) are reduced to the case of a saddle point inflation, for which 3. Parameter space for MSSM inflation 148