Measurement of string tension and initial temperature from transverse momentum spectra of heavy quarkonia in proton-proton collisions at the LHC

2025/06/12 by Zhang, Peng-Cheng, Zhu, Hailong, Liu, Fu-Hu +1
#FOS: Physical sciences #High Energy Physics - Experiment (hep-ex) #High Energy Physics - Phenomenology (hep-ph) #Nuclear Experiment (nucl-ex) #Nuclear Theory (nucl-th)

paper · doi:10.48550/arxiv.2506.10702

Abstract

The string tension (κ) in the Schwinger mechanism and the effective temperature (T) in Bose-Einstein statistics are extracted from the transverse momentum (p_T) spectra of heavy quarkonia produced in proton-proton (p+p) collisions at the Large Hadron Collider (LHC). Here, T derived from the heavy quarkonium p_T spectra also represents the initial temperature of the collision system, as transverse flow has not yet formed when heavy quarkonia are produced. The related parameters (κ and T) are obtained by fitting the experimental p_T spectra of J/ψ and Υ(nS) (n=1, 2, and 3) within various rapidity intervals, produced in p+p collisions at center-of-mass energies of √(s)=13 and 8 TeV, as measured by the LHCb Collaboration. It is found that the multi-component distribution structured within the framework of the Schwinger mechanism or Bose-Einstein statistics can effectively describe the heavy quarkonium p_T spectra in small collision systems. With decreasing rapidity in the forward region, both κ and T increase, indicating a directly proportional relationship between them. Based on κ, the average minimum strong force radius of participant quarks is determined.

Citations

• Comparing effective temperatures in standard and Tsallis distributions from transverse momentum spectra in small collision systems
• A Decade of Collectivity in Small Systems
• Collective phenomena study in small systems using the bulk of particle production in high-multiplicity pp collisions at √(s)= 13 TeV with ALICE
• Collectivity in small collision systems : an initial state perspective
• Initial Temperature and Extent of Chemical Equilibration of Partons in Relativistic Collision of Heavy Nuclei

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