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arXiv · 1704.07817

$A$-dependence of quasielastic charged-current neutrino-nucleus cross sections

Abstract

Background: 12C has been and is still widely used in neutrino-nucleus scattering and oscillation experiments. More recently, 40Ar has emerged as an important nuclear target for current and future experiments. Liquid argon time projection chambers (LArTPCs) possess various advantages in measuring electroweak neutrino-nucleus cross sections. Concurrent theoretical research is an evident necessity. Purpose: 40Ar is larger than 12C, and one expects nuclear effects to play a bigger role in reactions. We present inclusive differential and total cross section results for charged-current neutrino scattering on 40Ar and perform a comparison with 12C, 16O and 56Fe targets, to find out about the A-dependent behavior of model predictions. Method: Our model starts off with a Hartree-Fock description of the nucleus, with the nucleons interacting through a mean field generated by an effective Skyrme force. Long-range correlations are introduced by means of a continuum random phase approximation (CRPA) approach. Further methods to improve the accuracy of model predictions are also incorporated in the calculations. Results: We present calculations for 12C, 16O, 40Ar and 56Fe, showcasing differential cross sections over a broad range of kinematic values in the quasielastic regime. We furthermore show flux-folded results for 40Ar and we discuss the differences between nuclear responses. Conclusions: At low incoming energies and forward scattering we identify an enhancement in the 40Ar cross section compared to 12C, as well as in the high $ω$ (low $T_μ$ ) region across the entire studied $E_ν$ range. The contribution to the folded cross section of the reaction strength at values of $ω$ lower than 50 MeV for forward scattering is sizeable.

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Nils Van Dessel, Natalie Jachowicz, Raúl González-Jiménez, Vishvas Pandey, Tom Van Cuyck. 2018-03-26. $A$-dependence of quasielastic charged-current neutrino-nucleus cross sections. https://doi.org/10.1103/physrevc.97.044616

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