Primordial Non-Gaussianity in the Cosmic Microwave Background

Figure 5

Plot of the function 𝐹(1,𝑥₂,𝑥₃)𝑥²₂𝑥²₃ for the inflation with higher derivatives as given by (22) (a) and the ghost inflation as given by (23) (b). The figures are normalized to have value 1 for equilateral configurations 𝑥₂=𝑥₃=1 and set to zero outside the region 1−𝑥₂≤𝑥₃≤𝑥₂. Here 𝑥₃≡𝑘₃/𝑘₁ and 𝑥₂≡𝑘₂/𝑘₁. The figures are taken from Babich et al. 2003 [86].

(a)

(b)