Neutrino-nucleus cross sections for W -boson and trident production

Abstract

The physics of neutrino-nucleus cross sections is a critical probe of the Standard Model and beyond. A precise understanding is also needed to accurately deduce astrophysical neutrino spectra. At energies above ∼5 GeV, the cross section is dominated by deep inelastic scattering, mediated by weak bosons. In addition, there are subdominant processes where the hadronic coupling is through virtual photons, γ∗: (on-shell) W-boson production (e.g., where the underlying interaction is νℓ+γ∗→ℓ-+W+) and trident production (e.g., where it is ν+γ∗→ν+ℓ1-+ℓ2+). These processes become increasingly relevant at TeV-PeV energies. We undertake the first systematic approach to these processes (and those with hadronic couplings through virtual W and Z bosons), treating them together, avoiding common approximations, considering all neutrino flavors and final states, and covering the energy range 10-108 GeV. In particular, we present the first complete calculation of W-boson production and the first calculation of trident production at TeV-PeV energies. When we use the same assumptions as in prior work, we recover all of their major results. In a companion paper [this issue, Phys. Rev. D 101, 036010 (2020)PRVDAQ2470-001010.1103/PhysRevD.101.036010], we show that these processes should be taken into account for IceCube-Gen2.