Model of the CR(〈E〉), θ) relationship for θ = 0° using different CH₄ abundance profiles. In panel a, the red, blue, and green solid lines represent the CH₄ abundance profile from, respectively, the A and C eddy diffusion models of Moses et al. (2005) and Hue et al. (2018), and the Grodent et al. (2001) atmospheric model. In panel b is represented the modeled CR(〈E〉) relationship. The solid lines represent the CR modeled using kappa electron flux distribution and the dotted lines by using a mono-energetic flux distribution. The color conventions are the same as described for panel a. In panel c a zoomed-in version of panel b is shown to distinguish between the various CR(〈E〉) results at low energy.