Measurement of isolated photon-hadron correlations in sNN = 5.02 TeV pp and p -Pb collisions

Abstract

This paper presents isolated photon-hadron correlations using $pp$ and $p$-Pb data collected by the ALICE detector at the LHC. For photons with $|\ensuremath{\eta}|<0.67$ and $12<{p}_{\mathrm{T}}<40$ GeV/$c$, the associated yield of charged particles in the range $|\ensuremath{\eta}|<0.80$ and $0.5<{p}_{\mathrm{T}}<10$ GeV/$c$ is presented. These momenta are much lower than previous measurements at the LHC. No significant difference between $pp$ and $p$-Pb is observed, with Pythia 8.2 describing both data sets within uncertainties. This measurement constrains nuclear effects on the parton fragmentation in $p$-Pb collisions, and provides a benchmark for future studies of Pb-Pb collisions.