Studying baryon production using two-particle angular correlations

Małgorzata Anna Janik

doi:10.1051/epjconf/202023501004

Abstract

Latest measurements of ΔηΔφ correlations of identified particles show differences in particle production between baryons and mesons. The correlation functions for mesons exhibit the expected peak dominated by effects of mini-jet fragmentation and are reproduced well by general purpose Monte Carlo generators. For baryon pairs (where both particles have the same baryon number) a surprising near-side anti-correlation structure is observed instead of a peak, implying that two such particles are rarely produced with similar momentum. These results present a challenge to the contemporary models and there is no definite theoretical explanation of the observation. In this proceedings an overview of the latest baryon correlation measurements yielding startling results are presented.

Highlights

Two-particle angular correlations are a robust tool that enable the exploration of the underlying physics phenomena of particle production in collisions of both protons and heavy ions by studying the distributions of angles in ∆η∆φ space
The studies performed √by the ALICE Collaboration were √performed on proton–proton collisions with energy of s = 7 TeV, as well as energy of s = 13 TeV
F√igure 1 s = 13 shows correlations for the like-sign TeV pp collisions1 measured by the pairs of pions, kaons, ALICE experiment

Summary

Introduction

Two-particle angular correlations are a robust tool that enable the exploration of the underlying physics phenomena of particle production in collisions of both protons and heavy ions by studying the distributions of angles in ∆η∆φ space (where ∆η is the pseudorapidity difference and ∆φ is the azimuthal angle difference between two particles). These correlations open up the possibility to study a number of mechanisms simultaneously. The experimental results [1, 2] show that this peak is not observed for pairs of identical baryons

ALICE results

Definition of the correlation function

Results

STAR results

Discussion

Summary