Microscopic collectivity: The ridge and strangeness enhancement from string-string interactions

TL;DR

This paper introduces a microscopic model based on string-string interactions, such as shoving and rope hadronization, to explain collective effects like strangeness enhancement and the ridge in various collision systems, implemented in PYTHIA 8 and DIPSY.

Contribution

It develops and applies a microscopic model for collective effects using string interactions, successfully describing phenomena across different collision systems.

Findings

Rope hadronization explains strangeness enhancement in pp, pA, and AA collisions.

String shoving qualitatively reproduces the ridge in pp collisions.

The model is implemented in PYTHIA 8 and DIPSY event generators.

Abstract

We present the microscopic model for collective effects, built on string-string interactions (string shoving and rope hadronization), recently implemented in the PYTHIA 8 and DIPSY event generators. Rope hadronization is shown to give a good description of strangeness enhancement across pp, pA and AA collisions systems, while string shoving qualitatively describes the ridge observed in pp collisions.