Observation of strong nuclear suppression in exclusive ????/???? photoproduction in Au+Au ultraperipheral collisions at RHIC

• Titel: Observation of strong nuclear suppression in exclusive ????/???? photoproduction in Au+Au ultraperipheral collisions at RHIC
• Mitwirkende: Abdulhamid, Muhammad Ibrahim [VerfasserIn]
• Mitwirkende: Deppner, Ingo Martin [VerfasserIn]
• Mitwirkende: Herrmann, Norbert [VerfasserIn]
• Mitwirkende: Leung, Yue [VerfasserIn]
• Mitwirkende: Söhngen, Yannick [VerfasserIn]
• Körperschaft: STAR Collaboration [VerfasserIn]
• Verf.angabe: M.I. Abdulhamid, I.M. Deppner, N. Herrmann, Y.H. Leung, Y. Söhngen (STAR Collaboration)
• E-Jahr: 2024
• Jahr: 31 July, 2024
• Umfang: 9 S.
• Illustrationen: Illustrationen
• Fussnoten: Gesehen am 11.07.2025
• Titel Quelle: Enthalten in: Physical review letters
• Ort Quelle: College Park, Md. : APS, 1958
• Jahr Quelle: 2024
• Band/Heft Quelle: 133(2024), 5, Artikel-ID 052301, Seite 1-9
• ISSN Quelle: 1079-7114
• DOI: doi:10.1103/PhysRevLett.133.052301
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 193031051X

Abstract

We report a measurement of exclusive ????/???? and ????⁡(2⁢????) photoproduction in Au+Au ultraperipheral collisions at √????NN=200 GeV using the STAR detector. For the first time, (i) the ????⁡(2⁢????) photoproduction in midrapidity at the Relativistic Heavy-Ion Collider has been experimentally measured; (ii) nuclear suppression factors are measured for both the coherent and incoherent ????/???? production. At average photon-nucleon center-of-mass energy of 25.0 GeV, the coherent and incoherent ????/???? cross sections of Au nuclei are found to be 71 ±10% and 36 ±7%, respectively, of that of free protons. The stronger suppression observed in the incoherent production provides a new experimental handle to study the initial-state parton density in heavy nuclei. Data are compared with theoretical models quantitatively.