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.

One pion production in neutrino nucleon and neutrino nucleus interaction

Proceedings of The 21st international workshop on neutrinos from accelerators — PoS(NuFact2019), 2020

We very briefly describe the main ingredients, including the latest modifications, of the "HNV" model for one pion production in neutrino nucleon reactions. We present results for total cross sections as well as pion angular distributions with respect to the pion polar angles measured in the pion-nucleon center of mass. The latter show that the approximation of taking an isotropic distribution, as done in some Monte Carlo generators, is not supported by microscopic calculations. With the corresponding medium effects taken into account, the model is applied to one pion production in nuclei for which we show some preliminary results. The 21st international workshop on neutrinos from accelerators (NuFact2019) August 26-August 31, 2019 Daegu, Korea * Speaker.

First Measurement of Neutrino and Antineutrino Coherent Charged Pion Production on Argon

Physical Review Letters, 2014

We report on the first cross section measurements for charged current coherent pion production by neutrinos and antineutrinos on argon. These measurements are performed using the ArgoNeuT detector exposed to the NuMI beam at Fermilab. The cross sections are measured to be 2.7 +1.2 −0.9 (stat) +0.3 −0.4 (syst) × 10 −38 cm 2 /Ar for neutrinos at a mean energy of 9.6 GeV and 6.8 +2.5 −2.0 (stat) +0.8 −0.9 (syst) × 10 −39 cm 2 /Ar for antineutrinos at a mean energy of 3.6 GeV.

Q 2-dependence of backward pion multiplicity in neutrino–nucleus interactions

The production of pions emitted backward in inelastic neutrino-nucleus interactions is analyzed within the impulse approximation in the framework of the dual parton model. We focus on the Q 2 -dependence of the multiplicity of negative pions, normalized to the total cross section of the reaction ν + A → µ + X. The inclusion of planar (one-Reggeon exchange) and cylindrical (one-Pomeron exchange) graphs leads to a multiplicity that decreases as Q 2 increases, in agreement with recent measurements carried out at CERN by the NOMAD collaboration. A realistic treatment of the high momentum tail of the nucleon distribution in a nucleus also allows for a satisfactory description of the semi-inclusive spectrum of backward pions.

Single pi production in neutrino- nucleus scattering

Physical Review D, 2013

We study 1π production in both charged and neutral current neutrino nucleus scattering for neutrino energies below 2 GeV. We use a theoretical model for one pion production at the nucleon level that we correct for medium effects. The results are incorporated into a cascade program that apart from production also includes the pion final state interaction inside the nucleus. Besides, in some specific channels coherent π production is also possible and we evaluate its contribution as well. Our results for total and differential cross sections are compared with recent data from the MiniBooNE Collaboration. The model provides an overall acceptable description of data, better for N C than for CC channels, although theory is systematically below data. Differential cross sections, folded with the full neutrino flux, show that most of the missing pions lie in the forward direction and at high energies.

Neutrino induced coherent pion production

2010

We discuss different parameterizations of the C A 5 (q 2) N∆ axial form factor, fitted to the old Argonne bubble chamber data for pion production by neutrinos, and we use coherent pion production to test their low q 2 behavior. We find moderate effects that will be difficult to observe with the accuracy of present experiments. We also discuss the use of the Rein-Sehgal model for low energy coherent pion production. By comparison to a microscopic calculation, we show the weaknesses of some of the approximations in that model that lead to very large cross sections as well as to the wrong shapes for differential ones. Finally we show that models based on the partial conservation of the axial current hypothesis are not fully reliable for differential cross sections that depend on the angle formed by the pion and the incident neutrino.