Spin Response of Neutron Matter in <i>Ab Initio</i> Approach
J. E. Sobczyk, W. G. Jiang, Alessandro Roggero
Abstract
We propose a general method embedded in the ab initio nuclear framework to reconstruct linear response functions and calculate sum rules. Within our approach, based on the Gaussian integral transform, we consistently treat the ground state and the excited spectrum. Crucially, the method allows for a robust uncertainty estimation of the spectral reconstruction. We employ it to obtain the spin response in neutron matter. Our calculations are performed using state-of-the-art many-body coupled-cluster method and Hamiltonians derived in the chiral effective field theory, emphasizing the analysis of finite-size effects. Our findings reveal that the spin response exhibits a strong dependence on both nuclear interactions and many-body wave functions, offering a new avenue for exploring nuclear correlations and dynamics in infinite systems. This work serves as a stepping stone toward further studies of neutrino interactions in astrophysical environments from first principles.