Deciphering nonfemtoscopic two-pion correlations in $p+p$ collisions with simple analytical models

TL;DR

This paper introduces a simple analytical model to explain nonfemtoscopic two-pion correlations in proton-proton collisions, accounting for conservation laws and minijet effects, aligning well with experimental data.

Contribution

The paper presents a novel simple analytical model that reproduces nonfemtoscopic correlations observed in proton-proton collisions, highlighting the roles of conservation laws and minijets.

Findings

Model accurately reproduces ALICE data at 900 GeV

Correlations can arise from conservation laws and minijets

Similar effects may occur in hydrodynamic models with fluctuating initial conditions

Abstract

A simple model of nonfemtoscopic particle correlations in proton-proton collisions is proposed. The model takes into account correlations induced by the conservation laws as well as correlations induced by minijets. It reproduces well the two-pion nonfemtoscopic correlations of like-sign and unlike-sign pions in proton-proton collision events at $\sqrt{s} = 900$ GeV analyzed by the ALICE Collaboration. We also argue that similar nonfemtoscopic correlations can appear in the hydrodynamic picture with event-by-event fluctuating nonsymmetric initial conditions that are typically associated with nonzero higher-order flow harmonics.