Total SED recovered from the Fermi-LAT and MCMC constraint in the case of the reference model () when 4FGL J1256.9+2736 is replaced by the ICM component in the sky model (left) or both are included (right). The best-fit model is shown in black and the 68% confidence interval is show in blue, together with 100 models randomly sampled from the MCMC parameter chains. The median of these models is also shown as a dashed blue line. The residual provides the difference between the data and the best-fit model normalized by the error bars.