PAN Seminar: Tracing the baryon number in relativistic isobar collisions at RHIC
This event is in the past.
When:
December 1, 2023
3:30 p.m. to 4:30 p.m.
3:30 p.m. to 4:30 p.m.
Where:
Event category:
Seminar
In-person
Speaker: Gregoire Pihan (Wayne State)
Abstract:
Traditionally, the baryon number and electric charge within a proton are attributed to the valence quarks. However, a novel conceptualization known as the "baryon junction" challenges this paradigm by proposing that the baryon charge is associated with a Y-shaped, non-perturbative gluonic configuration inside hadrons. Recent preliminary analyses of isobar collisions at the Relativistic Heavy Ion Collider (RHIC) reveal that the scaled net-baryon to net-electric charge number ratio at midrapidity ($B/Delta Q * Delta Z/A$) falls within the range of 1.5 to 2. This aligns with predictions derived from the baryon junction model, marking a significant development. This outcome strongly suggests that, in high-energy collisions, the carrier of the baryon number is the baryon junction rather than the valence quarks. However, it is important to note that existing predictions pertain solely to the initial collision stage.
In this study, we establish a comprehensive (3+1)D relativistic hydrodynamic framework incorporating multiple conserved charge currents to systematically investigate this measurement from the initial to the final stage. Simulating the coupled propagation of net baryon and electric charge currents and incorporating a charge-dependent lattice-QCD-based equation of state, we explore the evolution of these charges throughout various phases of heavy-ion collisions. Our findings demonstrate that the aforementioned ratio, as measured in Ru+Ru and Zr+Zr collisions at $sqrt{s_mathrm{NN}}=200$ GeV, persists until the final stage, providing quantitative agreement with STAR preliminary measurements.