Soft and hard components of two-particle distributions on ($y_t,η,ϕ$) from p-p collisions at $\sqrt{s} = 200$ GeV

Abstract

We report measurements of large-scale two-particle correlations for 200 GeV p-p collisions on momentum components transverse rapidity $y_t$ (pion mass assigned), pseudorapidity $η$ and azimuth angle $ϕ$. In both transverse $y_t \otimes y_t$ and axial $(η\otimesη,ϕ\otimesϕ) $ two-particle subspaces we observe two components of correlation structure (soft and hard) which we interpret respectively in terms of longitudinal string fragmentation and transverse minimum-bias parton fragmentation (minijets). This combination is also represented by Lund-model-based Monte Carlo simulations such as Pythia.