CDN-253 completes the survey-validation phase of the GCFT dark-sector cluster programme. The locked CDN-242 κ-proxy is tested on Planck PSZ2, adding a fifth independent survey to previous validations from lensing, SZ, and X-ray selected cluster catalogs. The combined sample spans 10, 793 galaxy clusters across five surveys and redshifts from z = 0. 01 to z = 1. 91. Results show consistent proxy performance across all major public cluster catalogs, no evidence for redshift evolution in the mass–κ relationship, and a clearly identified domain boundary near M200 ≈ 1 × 10¹4 M☉. The study characterizes the proxy's universality, establishes its practical validity range, and concludes the large-scale survey validation phase of the GCFT cluster arc while outlining remaining theory-debt and group-scale reformulation tasks.
Nicky Joseph Hubertus Catharina Hacquier (Tue,) studied this question.