Spectral function for ${}^4$He using the Chebyshev expansion in coupled-cluster theory

Abstract

We compute spectral function for ${}^4$He by combining coupled-cluster theory with an expansion of integral transforms into Chebyshev polynomials. Our method allows to estimate the uncertainty of spectral reconstruction. The properties of the Chebyshev polynomials make the procedure numerically stable and considerably lower in memory usage than the typically employed Lanczos algorithm. We benchmark our predictions with other calculations in the literature and with electron scattering data in the quasi-elastic peak. The spectral function formalism allows one to extend ab-initio lepton-nucleus cross sections into the relativistic regime. This makes it a promising tool for modeling this process at higher energy transfers. The results we present open the door for studies of heavier nuclei, important for the neutrino oscillation programs.

12 pages, 5 figures

References in corpus (12)

• The Kernel Polynomial Method
• Accurate nuclear radii and binding energies from a chiral interaction
• A new parameterization of the nucleon elastic form factors
• Coupled-cluster theory for three-body Hamiltonians
• The Lorentz Integral Transform (LIT) method and its applications to perturbation induced reactions
• Electron- and neutrino-nucleus scattering from the quasielastic to the resonance region
• Optical potential from first principles
• Solution of the center-of-mass problem in nuclear structure calculations
• Giant and pigmy dipole resonances in 4He, 16,22O, and 40Ca from chiral nucleon-nucleon interactions
• Ab initio computation of the 17F proton-halo state and resonances in A = 17 nuclei
• The influence of the nuclear medium on inclusive electron and neutrino scattering off nuclei
• Electron Scattering and Neutrino Physics

Cited by in corpus (4)

• Revisiting the helium isotope-shift puzzle with improved uncertainties from nuclear structure corrections
• Faster spectral density calculation using energy moments
• Optimized binning for response function reconstruction via Chebyshev expansions
• Inclusive quasielastic (anti-)neutrino nucleus scattering within the Standard Model and beyond