Transport model study of conserved charge fluctuations and QCD phase transition in heavy-ion collisions
The RHIC-STAR (Relativistic Heavy Ion Collider-Solenoid Tracker at RHIC) experiments have measured the cumulants of net-proton (a proxy for net-baryon), net-charge, and net-kaon (proxy of net-strangeness) multiplicity distributions in Au+Au collisions at different centers of mass with energies rangi...
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| Format: | Article |
| Language: | zho |
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Science Press
2023-04-01
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| Series: | He jishu |
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| Online Access: | http://www.hjs.sinap.ac.cn/thesisDetails#10.11889/j.0253-3219.2023.hjs.46.040013&lang=zh |
| _version_ | 1797814513730322432 |
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| author | CHEN Qian MA Guoliang CHEN Jinhui |
| author_facet | CHEN Qian MA Guoliang CHEN Jinhui |
| author_sort | CHEN Qian |
| collection | DOAJ |
| description | The RHIC-STAR (Relativistic Heavy Ion Collider-Solenoid Tracker at RHIC) experiments have measured the cumulants of net-proton (a proxy for net-baryon), net-charge, and net-kaon (proxy of net-strangeness) multiplicity distributions in Au+Au collisions at different centers of mass with energies ranging from 7.7 GeV to 200 GeV. Recent results have shown that the ratio of the fourth-order net-proton cumulant over the second-order one (κσ2) exhibits a nonmonotonic energy dependence. In relativistic heavy-ion collision experiments, only information about the final state particles can be measured. Therefore, we investigated the fluctuations of the conserved charges (baryon, electric charge, and strangeness) in Au+Au collisions using a multiphase transport (AMPT) model. This model can basically describe the results measured by the RHIC-STAR experiment. More importantly, the AMPT model is used to understand the key impacts of the dynamical evolution of relativistic heavy-ion collisions on fluctuations and correlation functions, including the creation and diffusion of conserved charges, hadronization, hadronic rescatterings, and weak decays. It was discovered that the correlation between positive and negative charges may originate from the string melting mechanism. Baryon (proton) correlation functions are consistent with the expectation of baryon number conservation. Net-strangeness (net-kaon) originates from pair production. We studied the correspondence between representative quantities and their conserved charges and found that their behaviors are qualitatively consistent yet quantitatively different. Although the physics of quantum chromodynamics (QCD) critical fluctuations is not included in the AMPT model, our results are expected to provide a baseline for the search of possible critical behavior at the QCD critical end point in relativistic heavy-ion collisions. We incorporated critical density fluctuations into the model and found that they play a role. |
| first_indexed | 2024-03-13T08:08:49Z |
| format | Article |
| id | doaj.art-d01a53d7cff9450d94dde625c35142e9 |
| institution | Directory Open Access Journal |
| issn | 0253-3219 |
| language | zho |
| last_indexed | 2024-03-13T08:08:49Z |
| publishDate | 2023-04-01 |
| publisher | Science Press |
| record_format | Article |
| series | He jishu |
| spelling | doaj.art-d01a53d7cff9450d94dde625c35142e92023-06-01T02:35:26ZzhoScience PressHe jishu0253-32192023-04-0146404001304001310.11889/j.0253-3219.2023.hjs.46.0400130253-3219（2023）04-0177-28Transport model study of conserved charge fluctuations and QCD phase transition in heavy-ion collisionsCHEN Qian0MA Guoliang1CHEN Jinhui2(Key Laboratory of Nuclear Physics and Ion-beam Application (MOE), Institute of Modern Physics, Fudan University, Shanghai 200433, China)(Key Laboratory of Nuclear Physics and Ion-beam Application (MOE), Institute of Modern Physics, Fudan University, Shanghai 200433, China)(Key Laboratory of Nuclear Physics and Ion-beam Application (MOE), Institute of Modern Physics, Fudan University, Shanghai 200433, China)The RHIC-STAR (Relativistic Heavy Ion Collider-Solenoid Tracker at RHIC) experiments have measured the cumulants of net-proton (a proxy for net-baryon), net-charge, and net-kaon (proxy of net-strangeness) multiplicity distributions in Au+Au collisions at different centers of mass with energies ranging from 7.7 GeV to 200 GeV. Recent results have shown that the ratio of the fourth-order net-proton cumulant over the second-order one (κσ2) exhibits a nonmonotonic energy dependence. In relativistic heavy-ion collision experiments, only information about the final state particles can be measured. Therefore, we investigated the fluctuations of the conserved charges (baryon, electric charge, and strangeness) in Au+Au collisions using a multiphase transport (AMPT) model. This model can basically describe the results measured by the RHIC-STAR experiment. More importantly, the AMPT model is used to understand the key impacts of the dynamical evolution of relativistic heavy-ion collisions on fluctuations and correlation functions, including the creation and diffusion of conserved charges, hadronization, hadronic rescatterings, and weak decays. It was discovered that the correlation between positive and negative charges may originate from the string melting mechanism. Baryon (proton) correlation functions are consistent with the expectation of baryon number conservation. Net-strangeness (net-kaon) originates from pair production. We studied the correspondence between representative quantities and their conserved charges and found that their behaviors are qualitatively consistent yet quantitatively different. Although the physics of quantum chromodynamics (QCD) critical fluctuations is not included in the AMPT model, our results are expected to provide a baseline for the search of possible critical behavior at the QCD critical end point in relativistic heavy-ion collisions. We incorporated critical density fluctuations into the model and found that they play a role.http://www.hjs.sinap.ac.cn/thesisDetails#10.11889/j.0253-3219.2023.hjs.46.040013&lang=zhconserved chargefluctuationcumulantscorrelation functionsqcd phase transitioncritical end point (cep) |
| spellingShingle | CHEN Qian MA Guoliang CHEN Jinhui Transport model study of conserved charge fluctuations and QCD phase transition in heavy-ion collisions He jishu conserved charge fluctuation cumulants correlation functions qcd phase transition critical end point (cep) |
| title | Transport model study of conserved charge fluctuations and QCD phase transition in heavy-ion collisions |
| title_full | Transport model study of conserved charge fluctuations and QCD phase transition in heavy-ion collisions |
| title_fullStr | Transport model study of conserved charge fluctuations and QCD phase transition in heavy-ion collisions |
| title_full_unstemmed | Transport model study of conserved charge fluctuations and QCD phase transition in heavy-ion collisions |
| title_short | Transport model study of conserved charge fluctuations and QCD phase transition in heavy-ion collisions |
| title_sort | transport model study of conserved charge fluctuations and qcd phase transition in heavy ion collisions |
| topic | conserved charge fluctuation cumulants correlation functions qcd phase transition critical end point (cep) |
| url | http://www.hjs.sinap.ac.cn/thesisDetails#10.11889/j.0253-3219.2023.hjs.46.040013&lang=zh |
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