2023/10/24 by T. A. Trainor, Trainor, Thomas A.
Physics and Astronomy · #FOS: Physical sciences #High Energy Physics - Phenomenology (hep-ph) #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions
paper · pdf · doi:10.48550/arxiv.2310.16230
openalex publication_date 2023/10/24 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Nuclear modification factors (NMFs) applied to A-B collision systems consist of pt spectrum ratios rescaled by an estimated number of nucleon-nucleon binary collisions. Interest in NMFs is motivated by possible modification (suppression?) of jet production in more-central A-B collisions conjectured to arise from a deconfined quark-gluon plasma or QGP. Interpretation of NMFs is complicated by the so-called Cronin effect wherein similar ratios derived from fixed-target p-A data exhibited suppression at lower pt and enhancement at higher pt with increasing atomic weight A. This presentation describes precision analysis of identified-hadron spectra from 5 TeV p-Pb collisions that accurately isolates the entire jet contribution. Evolution of NMF spectrum ratios with p-Pb centrality is interpreted in terms of variation of corresponding jet contributions to spectra. The same method is then applied to Chicago-Princeton fixed-target spectrum data from the seventies wherein the Cronin effect was first observed. Soft and hard particle densities vary as fixed powers of A. Inferred jet contributions are quantitatively consistent with extrapolation from higher energies. The Cronin effect is a simple result of rescaling particle-density spectra by factor 1/A1/3.