Comprehensive analysis of the BSS population. Panel a: CMD showing the BSS selection box relative to the Padova isochrone and the empirical M67 ZAMS. Panel b: histogram of color offsets from the ZAMS, defining the blue and red sequences. Panel c: multiparameter binary identification matrix. Circle sizes are proportional to square of RUWE, and colors represent the image morphology (ipd_frac_multi_peak).