Measurement of Coherent π+ Production in Low Energy Neutrino-Carbon Scattering (original) (raw)

Coherent pion production in neutrino (anti-neutrino)-nucleus interaction

NPA, 2022

We present a study of coherent pion production in neutrino-nucleus interactions using the formalism based on partially conserved axial current theorem which connects the neutrino-nucleus cross section to the pion-nucleus elastic scattering cross section. Pion-nucleus elastic scattering cross section is calculated using Glauber model which takes three inputs, nuclear densities, pion-nucleon cross section and α πN which is the ratio of real to imaginary part of πN forward scattering amplitude, for which the parametrizations are obtained from measured data. We calculate the differential and integrated cross sections for charge and neutral current coherent pion production in neutrino (anti-neutrino)-nucleus scattering for a range of nuclear targets from light to heavy materials such as lithium, carbon, hydrocarbon, oxygen, silicon, argon, iron and lead. The results of these cross section calculations are compared with the measured data and with the calculations from the Berger-Sehgal model and GENIE package. There is an excellent agreement between the calculated and measured cross sections with Glauber model. While GENIE and Berger-Sehgal model give a good description of the data in the lower energy range the present calculations describe the data in all energy ranges. Predictions are also made for upcoming experiments like INO and DUNE in the coherent region of neutrino cross section.

Unified approach for nucleon knock-out and coherent and incoherent pion production in neutrino interactions with nuclei

Physical Review C, 2009

We present a theory of neutrino interactions with nuclei aimed at the description of the partial cross-sections, namely quasi-elastic and multi-nucleon emission, coherent and incoherent single pion production. For this purpose, we use the theory of nuclear responses treated in the random phase approximation, which allows a unified description of these channels. It is particularly suited for the coherent pion production where collective effects are important whereas they are moderate in the other channels. We also study the evolution of the neutrino cross-sections with the mass number from carbon to calcium. We compare our approach to the available neutrino experimental data on carbon. We put a particular emphasis on the multi-nucleon channel, which at present is not easily distinguishable from the quasi-elastic events. This component turns out to be quite relevant for the interpretation of experiments (K2K, MiniBooNE, SciBooNE). It can account in particular for the unexpected behavior of the quasi-elastic cross-section. PACS: 25.30.Pt, 13.15.+g, 24.10.Cn

Coherent pion production by neutrino scattering off nuclei

Physical Review D, 2006

The main part of coherent pion production by neutrinos on nuclei is essentially determined by PCAC, provided that the leptonic momentum transferred square Q 2 remains sufficiently small. We give the formulas for the charged and neutral current cross sections, including also the small non-PCAC transverse current contributions and taking into account the effect of the µ −-mass. Our results are compared with the experimental ones and other theoretical treatments.

Theoretical study of neutrino-induced coherent pion production off nuclei at T2K and MiniBooNE energies

Physical Review D, 2009

We have developed a model for neutrino-induced coherent pion production off nuclei in the energy regime of interest for present and forthcoming neutrino oscillation experiments. It is based on a microscopic model for pion production off the nucleon that, besides the dominant ∆ pole contribution, takes into account the effect of background terms required by chiral symmetry. Moreover, the model uses a reduced nucleon-to-∆ resonance axial coupling, which leads to coherent pion production cross sections around a factor two smaller than most of the previous theoretical estimates. In the coherent production, the main nuclear effects, namely medium corrections on the ∆ propagator and the final pion distortion, are included. We have improved on previous similar models by taking into account the nucleon motion and employing a more sophisticated optical potential. As found in previous calculations the modification of the ∆ self-energy inside the nuclear medium strongly reduces the cross section, while the final pion distortion mainly shifts the peak position to lower pion energies. The angular distribution profiles are not much affected by nuclear effects. Nucleon motion increases the cross section by ∼ 15% at neutrino energies of 650 MeV, while Coulomb effects on charged pions are estimated to be small. Finally, we discuss at length the deficiencies of the Rein-Sehgal pion coherent production model for neutrino energies below 2 GeV, and in particular for the MiniBooNE and T2K experiments. We also predict flux averaged cross sections for these two latter experiments and K2K.

Single pion production in neutrino reactions and estimates for charge-exchange effects

Nuclear Physics B, 2000

We calculate single pion production by neutrinos in the resonance region. We consider both charged and neutral current reactions on free protons and neutrons. We present differential and total cross sections which can be compared with experiments. Then we use these results to calculate the spectra of the emerging pions including the Pauli suppression factor and rescattering corrections for reactions in heavy nuclei. Our results will be useful for studying single pion production and for investigating neutrino oscillations in future experiments.

Nuclear Effects in Neutrino Induced Coherent Pion Production at K2K and MiniBooNE

Physical Review Letters, 2006

The coherent pion production induced by neutrinos in nuclei is studied using a delta hole model in local density approximation taking into account the renormalization of Delta\DeltaDelta properties in a nuclear medium. The pion absorption effects have been included in an eikonal approximation. These effects give a large reduction in the total cross section. The numerical results for the total cross section are found to be consistent with recent experimental results from K2K and MiniBooNE collaborations and other older experiments in the intermediate energy region.

Coherent pion production off nuclei at T2K and MiniBooNE energies revisited

Physical Review D, 2010

As a result of a new improved fit to old bubble chamber data of the dominant axial C A 5 nucleonto-Delta form factor, and due to the relevance of this form factor for neutrino induced coherent pion production, we re-evaluate our model predictions in Phys. Rev. D 79, 013002 (2009) for different observables of the latter reaction. Central values for the total cross sections increase by 20%∼30%, while differential cross sections do not change their shape appreciably. Furthermore, we also compute the uncertainties on total, differential and flux averaged cross sections induced by the errors in the determination of C A 5. Our new results turn out to be compatible within about 1σ with the former ones. Finally, we stress the existing tension between the recent experimental determination of the σ(CCcohπ +) σ(NCcohπ 0) ratio by the SciBooNE Collaboration and the theoretical predictions.

Neutrino-induced coherent pion production off nuclei

2009

All available theoretical estimates of neutrino-induced coherent pion production rely on the 'local approximation' for the Delta propagator. The validity of this approximation is scrutinized. It is found that the local approximation overestimates the neutrino-induced coherent pion production on nuclei significantly, by up to 100%.

Charged-current inclusive neutrino cross sections in the superscaling model including quasielastic, pion production and meson-exchange contributions

Journal of Physics G: Nuclear and Particle Physics, 2016

Charged current inclusive neutrino-nucleus cross sections are evaluated using the superscaling model for quasielastic scattering and its extension to the pion production region. The contribution of two-particle-two-hole vector meson-exchange current excitations is also considered within a fully relativistic model tested against electron scattering data. The results are compared with the inclusive neutrino-nucleus data from the T2K and SciBooNE experiments. For experiments where Eν ∼ 0.8 GeV, the three mechanisms considered in this work provide good agreement with the data. However, when the neutrino energy is larger, effects from beyond the ∆ also appear to be playing a role. The results show that processes induced by two-body currents play a minor role at the kinematics considered.