6533b81ffe1ef96bd1278745

RESEARCH PRODUCT

Jet transverse fragmentation momentum from h–h correlations in pp and p–Pb collisions

Jussi Viinikainen

subject

Nuclear and High Energy PhysicsParticle physicsp–PbFOS: Physical sciencesmomentumPartonppnucl-ex01 natural sciencesHigh Energy Physics - ExperimentNuclear physicsHigh Energy Physics - Experiment (hep-ex)ALICEjetfragmentationbranching0103 physical sciencesNuclear Physics - ExperimentNuclear Experiment (nucl-ex)showeringNuclear Experiment010306 general physicsNuclear ExperimentQuantum chromodynamicsPhysicsta114hep-ex010308 nuclear & particles physicsHigh Energy Physics::PhenomenologyPerturbative QCDObservableNuclear matterQCDHadronizationtransverseTransverse planeHigh Energy Physics::ExperimenthadronizationParticle Physics - ExperimentCoherence (physics)

description

QCD color coherence phenomena, like angular ordering, can be studied by looking at jet fragmentation. As the jet is fragmenting, it is expected to go through two different phases. First, there is QCD branching that is calculable in perturbative QCD. Next, the produced partons hadronize in a non-perturbative way later in a hadronization process. The jet fragmentation can be studied using the method of two particle correlations. A useful observable is the jet transverse fragmentation momentum $j_{\mathrm{T}}$, which describes the angular width of the jet. In this contribution, a differential study will be presented in which separate $j_{\mathrm{T}}$ components for branching and hadronization will be distinguished from the data measured by the ALICE experiment. The $p_{\mathrm{Tt}}$ dependence of the hadronization component $\sqrt{\left}$ is found to be rather flat, which is consistent with universal hadronization assumption. However, the branching component shows slightly rising trend in $p_{\mathrm{Tt}}$. The $\sqrt{s} = 7\,\mathrm{TeV}$ pp and $\sqrt{s_{\mathrm{NN}}} = 5.02\,\mathrm{TeV}$ p-Pb data give the same results within error bars, suggesting that this observable is not affected by cold nuclear matter effects in p-Pb collisions. The measured data will also be compared to the results obtained from PYTHIA8 simulations.

https://doi.org/10.1016/j.nuclphysbps.2017.05.067