{"title":"Examining the influence of hadronic interactions on the directed flow of identified particles in RHIC Beam Energy Scan energies using UrQMD model","authors":"Aswini Kumar Sahoo, Prabhupada Dixit, Md Nasim, Subhash Singha","doi":"10.1142/s0217732324500159","DOIUrl":null,"url":null,"abstract":"<p>The directed flow of identified particles can serve as a sensitive tool for investigating the interactions during initial and final states in heavy ion collisions. This study examines the rapidity distribution (<span><math altimg=\"eq-00001.gif\" display=\"inline\" overflow=\"scroll\"><mi>d</mi><mi>N</mi><mo stretchy=\"false\">∕</mo><mi>d</mi><mi>y</mi></math></span><span></span>), rapidity-odd directed flow (<span><math altimg=\"eq-00002.gif\" display=\"inline\" overflow=\"scroll\"><msub><mrow><mi>v</mi></mrow><mrow><mn>1</mn></mrow></msub></math></span><span></span>) and its slope (<span><math altimg=\"eq-00003.gif\" display=\"inline\" overflow=\"scroll\"><mi>d</mi><msub><mrow><mi>v</mi></mrow><mrow><mn>1</mn></mrow></msub><mo stretchy=\"false\">∕</mo><mi>d</mi><mi>y</mi></math></span><span></span>) for <span><math altimg=\"eq-00004.gif\" display=\"inline\" overflow=\"scroll\"><msup><mrow><mi>π</mi></mrow><mrow><mo>±</mo></mrow></msup></math></span><span></span>, <span><math altimg=\"eq-00005.gif\" display=\"inline\" overflow=\"scroll\"><msup><mrow><mi>K</mi></mrow><mrow><mo>±</mo></mrow></msup></math></span><span></span>, p, and <span><math altimg=\"eq-00006.gif\" display=\"inline\" overflow=\"scroll\"><mover accent=\"true\"><mrow><mstyle><mtext mathvariant=\"normal\">p</mtext></mstyle></mrow><mo>̄</mo></mover></math></span><span></span> in Au+Au collisions at different collision centralities and beam energies (<span><math altimg=\"eq-00007.gif\" display=\"inline\" overflow=\"scroll\"><msqrt><mrow><msub><mrow><mi>s</mi></mrow><mrow><mstyle><mtext mathvariant=\"normal\">NN</mtext></mstyle></mrow></msub></mrow></msqrt><mo>=</mo><mn>7</mn><mo>.</mo><mn>7</mn></math></span><span></span>, 11.5, 14.5, 19.6, 27, and 39<span><math altimg=\"eq-00008.gif\" display=\"inline\" overflow=\"scroll\"><mspace width=\".17em\"></mspace></math></span><span></span>GeV) using the UrQMD model. We investigate the impact of late-stage hadronic interactions on charge-dependent <span><math altimg=\"eq-00009.gif\" display=\"inline\" overflow=\"scroll\"><msub><mrow><mi>v</mi></mrow><mrow><mn>1</mn></mrow></msub><mo stretchy=\"false\">(</mo><mi>y</mi><mo stretchy=\"false\">)</mo></math></span><span></span> and its slope by modifying the duration of the hadronic cascade lifetime (<span><math altimg=\"eq-00010.gif\" display=\"inline\" overflow=\"scroll\"><mi>τ</mi></math></span><span></span>). The energy dependence of <span><math altimg=\"eq-00011.gif\" display=\"inline\" overflow=\"scroll\"><mi>d</mi><msub><mrow><mi>v</mi></mrow><mrow><mn>1</mn></mrow></msub><mo stretchy=\"false\">∕</mo><mi>d</mi><mi>y</mi></math></span><span></span> for p (<span><math altimg=\"eq-00012.gif\" display=\"inline\" overflow=\"scroll\"><mover accent=\"true\"><mrow><mstyle><mtext mathvariant=\"normal\">p</mtext></mstyle></mrow><mo>̄</mo></mover></math></span><span></span>) exhibits distinct pattern compared to <span><math altimg=\"eq-00013.gif\" display=\"inline\" overflow=\"scroll\"><msup><mrow><mi>π</mi></mrow><mrow><mo>±</mo></mrow></msup></math></span><span></span> and <span><math altimg=\"eq-00014.gif\" display=\"inline\" overflow=\"scroll\"><msup><mrow><mi>K</mi></mrow><mrow><mo>±</mo></mrow></msup></math></span><span></span>. Notably, we observe a change in the sign reversal position of proton <span><math altimg=\"eq-00015.gif\" display=\"inline\" overflow=\"scroll\"><mi>d</mi><msub><mrow><mi>v</mi></mrow><mrow><mn>1</mn></mrow></msub><mo stretchy=\"false\">∕</mo><mi>d</mi><mi>y</mi></math></span><span></span> at different beam energies with varying <span><math altimg=\"eq-00016.gif\" display=\"inline\" overflow=\"scroll\"><mi>τ</mi></math></span><span></span> in central and mid-central collisions. Moreover, the difference in <span><math altimg=\"eq-00017.gif\" display=\"inline\" overflow=\"scroll\"><mi>d</mi><msub><mrow><mi>v</mi></mrow><mrow><mn>1</mn></mrow></msub><mo stretchy=\"false\">∕</mo><mi>d</mi><mi>y</mi></math></span><span></span> between positively and negatively charged hadrons (<span><math altimg=\"eq-00018.gif\" display=\"inline\" overflow=\"scroll\"><mi mathvariant=\"normal\">Δ</mi><mi>d</mi><msub><mrow><mi>v</mi></mrow><mrow><mn>1</mn></mrow></msub><mo stretchy=\"false\">∕</mo><mi>d</mi><mi>y</mi></math></span><span></span>) demonstrates a stark centrality dependence for different particle species. The deuteron displays a significant increase in <span><math altimg=\"eq-00019.gif\" display=\"inline\" overflow=\"scroll\"><mi>d</mi><msub><mrow><mi>v</mi></mrow><mrow><mn>1</mn></mrow></msub><mo stretchy=\"false\">∕</mo><mi>d</mi><mi>y</mi></math></span><span></span> with increasing <span><math altimg=\"eq-00020.gif\" display=\"inline\" overflow=\"scroll\"><mi>τ</mi></math></span><span></span> compared to <i>p</i> and <i>n</i>. This investigation underscores the importance of considering the temporal evolution and duration of the hadronic phase when interpreting the sign reversal, charge splitting of <span><math altimg=\"eq-00021.gif\" display=\"inline\" overflow=\"scroll\"><msub><mrow><mi>v</mi></mrow><mrow><mn>1</mn></mrow></msub></math></span><span></span> and light nuclei formation at lower RHIC energies.</p>","PeriodicalId":18752,"journal":{"name":"Modern Physics Letters A","volume":null,"pages":null},"PeriodicalIF":1.5000,"publicationDate":"2024-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Modern Physics Letters A","FirstCategoryId":"101","ListUrlMain":"https://doi.org/10.1142/s0217732324500159","RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"ASTRONOMY & ASTROPHYSICS","Score":null,"Total":0}
引用次数: 0
Abstract
The directed flow of identified particles can serve as a sensitive tool for investigating the interactions during initial and final states in heavy ion collisions. This study examines the rapidity distribution (), rapidity-odd directed flow () and its slope () for , , p, and in Au+Au collisions at different collision centralities and beam energies (, 11.5, 14.5, 19.6, 27, and 39GeV) using the UrQMD model. We investigate the impact of late-stage hadronic interactions on charge-dependent and its slope by modifying the duration of the hadronic cascade lifetime (). The energy dependence of for p () exhibits distinct pattern compared to and . Notably, we observe a change in the sign reversal position of proton at different beam energies with varying in central and mid-central collisions. Moreover, the difference in between positively and negatively charged hadrons () demonstrates a stark centrality dependence for different particle species. The deuteron displays a significant increase in with increasing compared to p and n. This investigation underscores the importance of considering the temporal evolution and duration of the hadronic phase when interpreting the sign reversal, charge splitting of and light nuclei formation at lower RHIC energies.
期刊介绍:
This letters journal, launched in 1986, consists of research papers covering current research developments in Gravitation, Cosmology, Astrophysics, Nuclear Physics, Particles and Fields, Accelerator physics, and Quantum Information. A Brief Review section has also been initiated with the purpose of publishing short reports on the latest experimental findings and urgent new theoretical developments.