Anisotropic flow fluctuation as a possible signature of clustered nuclear geometry in O-O collisions at the Large Hadron Collider

Nuclei having 4n number of nucleons are theorized to possess clusters of particles (⁴He nucleus). The Oxygen nucleus (^16O) is a doubly magic nucleus, where the presence of an -clustered nuclear structure grants additional nuclear stability. In this study, we exploit the anisotropic flow coefficients to discern the effects of an -clustered nuclear geometry w. r. t. a Woods-Saxon nuclear distribution in O--O collisions at s ₍₍=7 TeV using a hybrid of IP-Glasma + MUSIC + iSS + UrQMD models. In addition, we use the multi-particle cumulants method to measure anisotropic flow coefficients, such as elliptic flow (v₂) and triangular flow (v₃), as a function of collision centrality. Anisotropic flow fluctuations, which are expected to be larger in small collision systems, are also studied for the first time in O--O collisions. It is found that an -clustered nuclear distribution gives rise to an enhanced value of v₂ and v₃ towards the highest multiplicity classes. Consequently, a rise in v₃/v₂ is also observed for the (0-10) \% centrality class. Further, for -clustered O--O collisions, fluctuations of v₂ are larger for the most central collisions, which decrease towards the mid-central collisions. In contrast, for a Woods-Saxon ^16O nucleus, v₂ fluctuations show an opposite behavior with centrality. This study, when confronted with experimental data may reveal the importance of nuclear density profile on the discussed observables.