Minijet clustering algorithm using transverse-momentum seeds in high-energy nuclear collisions

We propose an algorithm to detect minijet clusters in high-energy nuclear collisions, by selecting a hightransverse-momentum (pT ) particle as a seed and assigning a clustering radius (R) in the pseudorapidity and azimuthal-angle space. Our PYTHIA simulations for p + p collisions show that a scheme with a seeding pT of around 0.5 GeV/c and R of approximately 0.6 satisfactorily identifies minijet clusters. The correlation between clusters obtained in PYTHIA calculations using the algorithm exhibits the proper behavior of hard-scattering-like processes, suggesting its usefulness in isolating minijet-like clusters from nonhard-scattering soft processes when applied to actual nuclear-collision data, thereby allowing a closer examination of both the minijet and the soft mechanisms.