Phenomenological investigation of order statistics for multi-jet events

Abstract

We investigate rank-ordered jet rapidity distributions as probes of multijet radiation in proton-proton collisions at $\sqrt{s}=13$ TeV. These observables retain information about the organization of jets within an event that is not resolved by the inclusive single-jet rapidity spectrum. We compare normalized predictions from the BFKL-based generator BFKLex and the collinear parton-shower generator PYTHIA 8.306, considering both fixed three-jet configurations and rank observables defined across multiplicities. We assess PDF and tune variations for PYTHIA 8.306, and PDF and factorization- and renormalization-scale variations for BFKLex. Total-variation and Wasserstein distances quantify the separation between the baseline shapes. Differences remain visible relative to the evaluated uncertainty bands in several well-populated regions. A minimum rapidity separation between the extremal jets modifies the discriminating power of the observables in a rank-dependent way. These results support rank-ordered rapidity spectra as experimentally accessible observables complementary to conventional Mueller-Navelet measurements for investigating high-energy QCD radiation.