Blue fraction as a function of the cluster dynamical state, in two mass bins. Left: average blue fraction as a function of the cluster dynamical state, in two mass bins. Right: blue fraction as a function of σ_cl (top) and L_X (bottom) for each of the two mass bins. The solid and dotted black and blue lines represent the average fractions with 1σ errors for relaxed and cluster mergers, respectively. The blue fractions, dominated mostly by spiral galaxies, are similar in post-mergers and relaxed clusters for the lower-mass bin. Moreover, the blue fractions as a function of global cluster properties remain constant within 1σ errors for post-mergers. The relaxed clusters, on the other hand, show a lot of scatter in the blue fractions as a function of σ_cl and L_X.