MCMC constraints on the model parameters, in the case of the reference model () when 4FGL J1256.9+2736 is excluded from the sky model (green) or included (orange). Bottom left panel: constraint in the plane X_CRp(R₅₀₀)−α_CRp, where the contours correspond to 68% and 95% confidence interval. The marginalized posterior probability distributions are also shown for the parameters X_CRp(R₅₀₀) (top) and α_CRp (right), where the shaded area provides the 68% confidence interval.