Speaker
Description
High-energy heavy-ion collisions offer a unique and precise way to probe nuclear structures by providing a snapshot of the nuclear distribution at the time of the collision, which is complementary to low-energy nuclear physics experiments.
In this talk, we present a comprehensive scan of flow observables, including anisotropic flow coefficients, nonlinear flow modes, and normalized symmetric cumulants, in Pb--Pb and Xe--Xe collisions measured with ALICE at $\sqrt{s_\mathrm{NN}} =$ 5.02 and 5.44 TeV, respectively. These measurements can probe distinctive nuclear structures (i.e., quadrupole deformation) in central collisions and the size of the $^{208}$Pb neutron skin in midcentral to peripheral collisions. The measurements of multiparticle cumulants of mean transverse momentum, $[p_\mathrm{T}]$, allow us to probe the size and its fluctuations in the initial state. Furthermore, we present the first measurements of newly proposed multiparticle cumulants between anisotropic flow $v_{\rm n}^{\rm m}$ (m = 2,4) and mean transverse momentum correlations $[p_\mathrm{T}^{(k)}]$ (k $\leq$ 4), in both Pb--Pb and Xe--Xe collisions. The presented measurements and comparisons to the state-of-the-art theoretical model calculations show unambiguous evidence of a deformed and triaxial structure for $^{129}$Xe, and in Pb--Pb collisions further provide tight constraints to the nucleon width $w$, which was poorly controlled before. These studies enormously improve our understanding of the initial conditions of heavy-ion collisions and allow us to explore LHC's full potential as a robust nuclear physics machine.
| Category | Experiment |
|---|---|
| Collaboration (if applicable) | ALICE |
