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Register a new userUnraveling the Flux-Averaged Neutrino-Nucleus Cross Section
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Authors
Omar Benhar
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The interpretation of the nuclear cross sections measured using accelerator neutrino beams involve severe difficulties, arising primarily from the average over the incoming neutrino flux. The broad energy distribution of the beam particles hampers the determination of the energy transfer to the nuclear target, the knowledge of which is needed to pin down the dominant reaction mechanism. Overcoming this problem requires the development of a theoretical approach suitable to describe neutrino interactions at energies ranging from hundreds of MeV to few GeV. In this paper, it is argued that the approach based on the factorisation of the nuclear cross section provides a consistent framework for the calculation of neutrino-nucleus interactions in both the quasi elastic and inelastic channels. The near-degeneracy between theoretical models based on different assumptions, and the use of electron scattering data to advance the understanding of neutrino-nucleus cross sections are also discussed.
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The inclusive neutrino/antineutrino-induced charged and neutral current reaction cross-sections in $^{12}C$, $^{16}O$, $^{40}Ar$, $^{56}Fe$ and $^{208}Pb$ in the energy region of supernova neutrinos/antineutrinos are studied. The calculations are performed in the local density approximation (LDA) taking into account the effects due to Pauli blocking, Fermi motion and the renormalization of weak transition strengths in the nuclear medium. The effect of Coulomb distortion of the lepton produced in the charged current reactions has also been included. The numerical results for the energy dependence of the cross-section $sigma(E)$ as well as the flux averaged cross-section and event rates for the charged lepton production in the case of some supernova neutrino/antineutrino fluxes recently discussed in the literature have been presented. We have also given the flux-averaged angular and energy distributions of the charged leptons corresponding to these fluxes.
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