Linking chiral nuclear forces to light-ion collisions: a global sensitivity analysis

Abstract

Ultrarelativistic $^{16}$O+$^{16}$O and $^{20}$Ne+$^{20}$Ne collisions recently performed at the Large Hadron Collider have imaged quadrupole and octupole correlations between nucleons through the collective flow of emitted hadrons. We establish a quantitative link between these correlations and the low-energy constants (LECs) that enter chiral inter-nucleon interactions. Emulators built using the subspace-projected coupled-cluster method enable a global sensitivity analysis of the ground-state quadrupole mean-square eccentricity, revealing that quadrupole correlations respond linearly and additively to all 16 LECs at next-to-next-to-leading order in the chiral expansion. The sensitivities differ markedly in $^{16}$O and $^{20}$Ne, and are complementary to those of the binding energy and charge radius, the bulk observables to which nuclear interactions are typically calibrated. In particular, $^{20}$Ne collisions dominantly probe the spin-orbit part of two-nucleon interactions. Soft-particle correlations in light-ion collisions thus constitute a new type of data to study nuclear forces and their emergence from quantum chromodynamics.