- 1School of Physics and Mechanical Electrical & Engineering, Hubei University of Education, Wuhan, China
- 2Institute of Astronomy and High Energy Physics, Hubei University of Education, Wuhan, China
- 3Wuhan Textile University, Wuhan, China
We employed the dynamically constrained phase space coalescence model to study the
1 Introduction
Hadron spectroscopy is a field replete with frequent discoveries and surprises, and the theoretical complexities associated with understanding the strong interaction in the color confinement regime make the field even more fascinating. A very successful classification scheme for hadrons in terms of their valence quarks and antiquarks was independently proposed by Murray Gell-Mann [1] and George Zweig [2] in 1964. This classification, known as the quark model, essentially divides hadrons into two major families: mesons (quark-antiquark) and baryons (three-quarks). Theoretically, the basic theory of the strong interaction, quantum chromodynamics (QCD), allows for the existence of exotic hadrons beyond the conventional picture.
The first quarkonium-like state, the
The production yields of exotic states in high-energy collisions, which are expected to be strongly influenced by their internal structure, have received increasing attention [10–18]. The internal structure of exotic hadrons is still under debate. They are assumed to be loosely bound hadronic molecule, a compact tetraquark, or just a kinematic effect such as the triangle singularity, etc [8, 9]. The internal structure and interactions of compact multiquark states and hadronic molecular states have been extensively studied. The former are bound by the strong interaction directly, while the latter are bound by residual strong interaction [8, 9, 19].
The abundant number of quarks and antiquarks for both light and heavy flavors suggests that heavy-ion collisions provide an ideal environment for exotic hadron production, compared to electron-positron and proton-proton (or antiproton) collisions. The first evidence for the
2 Model
The PACIAE model [20–22] is a parton and hadron cascade model based on PYTHIA [23]. It has been successfully used to describe particle multiplicity, transverse momentum, rapidity distributions, and other observables in high-energy collisions [17, 24–27]. The PACIAE Monte-Carlo (MC) simulation provides a complete description of one collision, which includes the partonic initialization stage, partonic rescattering stage, hadronization stage, and the hadronic rescattering stage. For nucleon-nucleon (NN) collisions, compared to PYTHIA, the partonic and hadronic rescattering are introduced before and after the hadronization, respectively. The initial-state free parton is produced by breaking the strings of quarks, antiquarks, and gluons formed in the Pb-Pb collision with the PACIAE model. The parton rescattering is further considered using the
The DCPC model was proposed to study production of the light nuclei in
Here,
Therefore, the yield of an
where,
The
The DCPC model has been successfully applied to different collision systems at RHIC and LHC, including
3 Result
In this work, we produce the
In the production of final states particles with PACIAE, the impact parameter

Table 1. The comparisons of the yield of
In this work, the

Figure 1. Radius distributions of
Then, we calculate the yields of three structures of the

Figure 2. Mass distributions of the
As a reasonable prediction, we can predict the yields of the
Moreover, we calculate the transverse momentum distribution of the tetraquark, nuclear-like and molecular states the

Figure 3. The transverse momentum distributions of the
In Figure 3, we show the predicted pT-differential yields of the tetraquark, nuclear-like and molecular states of the

Figure 4. The yield ratio for
From Figure 4, we observe that the yield ratio for the
4 Conclusion
In this paper, we study the production of the
Data availability statement
The original contributions presented in the study are included in the article/supplementary material, further inquiries can be directed to the corresponding author.
Author contributions
HX: Conceptualization, Data curation, Formal Analysis, Investigation, Methodology, Software, Validation, Writing – original draft, Writing – review and editing. ZS: Data curation, Resources, Software, Writing – review and editing. NY: Conceptualization, Funding acquisition, Project administration, Writing – review and editing. ZZ: Investigation, Methodology, Validation, Writing – review and editing.
Funding
The author(s) declare that financial support was received for the research and/or publication of this article. This work is supported by the Scientific Research Foundation of Hubei University of Education for Talent Introduction (No. ESRC20230002 and No. ESRC20230007) and Research Project of Hubei Provincial Department of Education (No. D20233003 and No. B2023191).
Conflict of interest
The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
Generative AI statement
The author(s) declare that no Generative AI was used in the creation of this manuscript.
Publisher’s note
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Keywords: heavy ion collision, exotic hadron, hadronic molecular state, tetraquark state, nuclear-like state
Citation: Xu H, She Z, Yu N and Zhang Z (2025) Production of the
Received: 01 April 2025; Accepted: 20 June 2025;
Published: 09 July 2025.
Edited by:
Shahin Agaev, Baku State University, AzerbaijanReviewed by:
Atif Arif, COMSATS University, PakistanFabrizio Grosa, European Organization for Nuclear Research (CERN), Switzerland
Copyright © 2025 Xu, She, Yu and Zhang. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
*Correspondence: Ning Yu, bmluZy55dWNoaW5hQGdtYWlsLmNvbQ==