Studying baryon production using two-particle angular correlations

TL;DR

This paper investigates two-particle angular correlations of baryons and mesons, revealing unexpected anti-correlation patterns for baryons that challenge existing theoretical models.

Contribution

It presents new measurements of baryon correlations showing a surprising anti-correlation, highlighting a gap in current theoretical understanding.

Findings

Mesons show expected peak in correlation functions.

Baryon pairs exhibit near-side anti-correlation.

Results challenge current particle production models.

Abstract

Latest measurements of $\Delta\eta\Delta\varphi$ 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.