BEGIN:VCALENDAR VERSION:2.0 PRODID:-//CERN//INDICO//EN BEGIN:VEVENT SUMMARY:Imaging the longitudinal structure of the QGP using different shap ed nuclei DTSTART:20261027T023000Z DTEND:20261027T033000Z DTSTAMP:20261103T172700Z UID:indico-event-31274@indico.ihep.ac.cn DESCRIPTION:Speakers: Jiangyong Jia (SBU & BNL)\n\nHow energy is deposited along the beam direction\, and how it fluctuates\, is the least constrain ed part of the initial state of heavy-ion collisions. Accessing this struc ture is notoriously difficult because of short-range nonflow correlations\ , and the traditional observable r2(η) provides only incomplete and biase d information about longitudinal decorrelation. Isobar-like collisions hav e been used to image the shapes of atomic nuclei\; here we introduce a str ategy that turns nuclear shape into a controlled instrument for the longit udinal structure of the QGP. A change in nuclear shape perturbs the longit udinal geometry while leaving the nonflow background and the final-state r esponse essentially unchanged. In AMPT simulations of central U+U and Au+A u collisions we extract the full two-particle rapidity correlation map， which reveals a nonlinear\, nonadditive loss of correlation and a previous ly unquantified acceptance-dependent bias in standard flow measurements\, about 16% for references four units from mid-rapidity. This idea can be di rectly applied to understand longitudinal fluctuations in ellipticity\, tr iangularity and transverse size using existing U+U/Au+Au\, Ru+Ru/Zr+Zr and O+O/Ne+Ne data. In small systems it can determine whether this bias expla ins the long-standing flow puzzle. Nuclear structure thus becomes a precis ion instrument for three-dimensional imaging of the QGP initial conditions .Bio:Jiangyong Jia is a professor in Stony Brook University (SBU) and phys icist in Brookhaven National Laboratory (BNL). He is member of RHIC-STAR a nd LHC-ATLAS\, and previously the RHIC-PHENIX experiments\, with broad int erests in high energy nuclear physics and particle physics. However\, his main expertise is in the area of collective flow\, hydrodynamics and parti cle correlations from small to large collision systems. He received his B. S. degree from USTC in 1997\, Ph.D. from SBU in 2003\, worked as a postdoc in Columbia University\, before joining the faculty at SBU and BNL in 200 6.\n\nhttps://indico.ihep.ac.cn/event/31274/ LOCATION:B105 (CHEP) URL:https://indico.ihep.ac.cn/event/31274/ END:VEVENT END:VCALENDAR