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Effects of overlapping strings in pp collisions

  • Christian Bierlich
  • Gösta Gustafson
  • Leif Lönnblad
  • Andrey Tarasov
Open Access
Regular Article - Theoretical Physics

Abstract

In models for hadron collisions based on string hadronization, the strings are usually treated as independent, allowing no interaction between the confined colour fields. In studies of nucleus collisions it has been suggested that strings close in space can fuse to form “colour ropes”. Such ropes are expected to give more strange particles and baryons, which also has been suggested as a signal for plasma formation. Overlapping strings can also be expected in pp collisions, where usually no phase transition is expected. In particular at the high LHC energies the expected density of strings is quite high. To investigate possible effects of rope formation, we present a model in which strings are allowed to combine into higher multiplets, giving rise to increased production of baryons and strangeness, or recombine into singlet structures and vanish. Also a crude model for strings recombining into junction structures is considered, again giving rise to increased baryon production. The models are implemented in the dipsy MC event generator, using Pythia8 for hadronization, and comparison to pp minimum bias data, reveals improvement in the description of identified particle spectra.

Keywords

QCD Phenomenology Monte Carlo Simulations 

Notes

Open Access

This article is distributed under the terms of the Creative Commons Attribution License (CC-BY 4.0), which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited.

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Copyright information

© The Author(s) 2015

Authors and Affiliations

  • Christian Bierlich
    • 1
  • Gösta Gustafson
    • 1
  • Leif Lönnblad
    • 1
  • Andrey Tarasov
    • 2
  1. 1.Dept. of Astronomy and Theoretical PhysicsLund UniversityLundSweden
  2. 2.Theory CenterJefferson LabNewport NewsU.S.A.

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