Observation of multiplicity dependent prompt χc1 (3872) and ψ (2S) production in pp collisions

Research output: Contribution to journalArticlepeer-review

Authors

  • LHCb Collaboration

Colleges, School and Institutes

External organisations

  • Nikhef National Institute for Subatomic Physics
  • University of Zurich
  • University of Liverpool
  • Universidad de Santiago de Compostela
  • University of Bristol
  • Université Clermont Auvergne
  • University of Michigan, Ann Arbor.
  • Istituto Nazionale di Fisica Nucleare, Sezione di Milano
  • University of Cincinnati
  • Technische Universität Dortmund
  • CERN
  • University of Glasgow
  • Universitat Autònoma de Barcelona
  • University of Manchester
  • Petersburg Nuclear Physics Institute (PNPI)
  • Universidade Federal Do Rio de Janeiro
  • Université Paris-Saclay
  • Sezione INFN di Firenze
  • Sezione INFN di Ferrara
  • Ruprecht-Karls-Universität Heidelberg
  • Institute for High Energy Physics (IHEP)
  • Syracuse University
  • Yandex School of Data Analysis
  • IN2P3
  • Laboratory of Photonics and Interfaces, Department de Chimie, Ecole Polytechnique Federale de Lausanne, CH-1015 Lausanne, Switzerland. ahmad@mpip-mainz.mpg.de
  • Warwick University
  • Imperial College London
  • Sezione di Perugia
  • Instituto Galego de Física de Altas Enerxías (IGFAE)
  • Chinese Academy of Sciences

Abstract

The production of χc1(3872) and ψ(2S) hadrons is studied as a function of charged particle multiplicity in pp collisions at a center-of-mass energy of 8 TeV, corresponding to an integrated luminosity of 2 fb-1. For both states, the fraction that is produced promptly at the collision vertex is found to decrease as charged particle multiplicity increases. The ratio of χc1(3872) to ψ(2S) cross sections for promptly produced particles is also found to decrease with multiplicity, while no significant dependence on multiplicity is observed for the equivalent ratio of particles produced away from the collision vertex in b-hadron decays. This behavior is consistent with a calculation that models the χc1(3872) structure as a compact tetraquark. Comparisons with model calculations and implications for the binding energy of the χc1(3872) state are discussed.

Bibliographic note

Publisher Copyright: © 2021 CERN.

Details

Original languageEnglish
Article number092001
Number of pages11
JournalPhysical Review Letters
Volume126
Issue number9
Publication statusPublished - 5 Mar 2021

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