Scaling approach to nuclear structure in high-energy heavy-ion collisions

TL;DR

This paper introduces a scaling relation linking nuclear structure parameters to experimental observables in high-energy heavy-ion collisions, enabling precise probing of initial conditions and nuclear shapes.

Contribution

It presents a novel scaling approach that connects nuclear structure parameters with collision observables, aiding in constraining initial conditions and nuclear shapes in heavy-ion collisions.

Findings

Scaling relation between nuclear parameters and observables

Observable ratios depend only on parameter differences

Application to isobar collisions reveals nuclear structure effects

Abstract

In high-energy heavy-ion collisions, the initial condition of the produced quark-gluon plasma (QGP) and its evolution are sensitive to collective nuclear structure parameters describing the shape and radial profiles of the nuclei. We find a general scaling relation between these parameters and many experimental observables such as elliptic flow, triangular flow, and particle multiplicity distribution. In particular, the ratios of observables between two isobar systems depend only on the differences of these parameters, but not on the details of the final state interactions, hence offering a new way to constrain the QGP initial condition. Using this scaling relation, we show how the structure parameters of $^{96}_{44}$Ru and $^{96}_{40}$Zr conspire to produce the rich centrality dependences of these ratios, as measured by the STAR Collaboration. Our scaling approach demonstrates that isobar collisions are a precision tool to probe the initial condition of heavy-ion collisions, as well as the collective nuclear structures, including the neutron skin, of the atomic nuclei across energy scales.