Multiplicity Dependence of Two-particle Correlation in $pp$ and $p$Pb at the LHCb

This paper shows that two-particle correlation function depends on multiplicity in proton–proton (pp) collisions at p s = 13 TeV and proton–lead (pPb) collisions at p sNN = 5:02 TeV using results from the LHCb experiment. Results show azimuthal anisotropies in the event shape, the so-called near-side ridge in long-range . The near-side ridge in a small system has been understood as the collective behaviour of emitted particles in the collisions.