2025/02/27 by ALICE Collaboration
#FOS: Physical sciences #High Energy Physics - Experiment (hep-ex) #Nuclear Experiment (nucl-ex)
paper · doi:10.48550/arxiv.2502.19956
We present the measurement of the p\rm T-differential production cross section of ω mesons in pp and p-Pb collisions at √s\rm NN = 5.02 TeV at midrapidity by ALICE. In addition, the first measurement of the nuclear modification factor RpPb for ω mesons at LHC energies is presented, complementing the existing measurements of lighter neutral mesons such as the π0 and η. Within the measured p\rm T-range, the RpPb of ω mesons is compatible with no cold nuclear matter effects within the uncertainties, consistent with previous measurements at lower energies. The ω/π0 ratio is presented for both collision systems, showing no collision system dependence within the uncertainties. The comparison to previously published ω/π0 ratios at lower and higher collision energies in pp collisions suggests a decreasing trend of the ratio above p\rm T=~4 GeV/c with increasing collision energy. The data in both collision systems are compared to predictions from PYTHIA, EPOS LHC and DPMJET event generators, revealing significant shortcomings in these models' ability to describe the production of ω mesons.